Core Concept 33.8***
Corticosteroids are prescribed for adrenocortical insufficiency- and to dampen inflammatory and immune responses.
Symptoms of adrenocortical insufficiency include hypoglycemia, unusual fatigue, orthostatic hypotension, darkening skin pigmentation, joint pain, and GI disturbances such as anorexia, vomiting, and diarrhea. Low plasma levels of Cortisol, accompanied by high plasma levels of ACTH, indicate that the adrenal gland is not responding to ACTH stimulation. Primary adrenocortical insufficiency, known as Addison disease, is quite rare and includes a deficiency of both glucocorticoids and mineralocorticoids. Secondary adrenocortical insufficiency is more common than primary and can occur when corticosteroids are suddenly withdrawn during pharmacotherapy.
When corticosteroids are taken as medications for prolonged periods, they provide negative feedback to the pituitary to stop secreting ACTH. Without stimulation by ACTH, the adrenal cortex shrinks and stops secreting endogenous corticosteroids, a condition known as adrenal atrophy. The goal of replacement therapy is to achieve the same physiologic level of corticosteroids in the blood that would be present if the adrenal glands were functioning properly. Abrupt withdrawal of corticosteroids may cause adrenal crisis, a medical emergency, requiring immediate treatment. Gradual withdrawal of corticosteroids is considered in some cases; however, patients requiring replacement therapy generally must take corticosteroids their entire lifetime, and concurrent therapy with a mineralocorticoid such as fludrocortisone (Florinef) is essential. Selected corticosteroids are listed in Table 33.4.
In addition to treating adrenal insufficiency, corticosteroids are prescribed for a large number of nonendocrine disorders. Their ability to suppress inflammatory and immune responses quickly and effectively gives them tremendous therapeutic utility to treat a diverse set of conditions, including shock, swelling, post-transplant surgery, some cancers, allergies, asthma, inflammatory bowel disease, and some rheumatic and skin disorders.
Cushing syndrome occurs when high levels of corticosteroids are present in the body over a prolonged period.
Table 33.4 Selected Corticosteroids
Drug
Route and Adult Dose
Remarks
SHORT ACTING
cortisone
PO: 20-300 mg/day
IM form available; has mineralocorticoid activity
*** hydrocortisone (Cortef, Solu-Cortef)
PO: 10-320 mg/day in divided doses IV/IM; 15-800 mg/day in divided doses (max: 2 g/day)
Topical form available; has both glucocorticoid and mineralocorticoid activity
INTERMEDIATE ACTING
methylprednisolone (Depo-Medrol, Medrol, Medrol Dosepak, others)
PO: 2-60 mg one to four times per day
IV and IM forms available; has little mineralocorticoid activity
prednisolone
PO: 5-60 mg one to four times per day
IV and IM forms available; has little mineralocorticoid activity
prednisone (see the Prototype Drug box In Core Concept 25.5)
PO: 5-60 mg one to four times per day
Has little mineralocorticoid activity
triamcinolone (Aristospan, Kenalog)
PO: 4-48 mg one to two times per day
IV, intra-articular, subcutaneous, topical, inhalation, and IM forms available; has little mineralocorticoid activity
LONG ACTING
betamethasone (Celestone, Diprolene, others)
PO: 0.6-7.2 mg/day IM: 0.5-9 mg/day
IV, topical, and IM forms available; has little mineralocorticoid activity
dexamethasone
IM: 8-16 mg bid-qid PO: 0.25-4 mg bid-qid
IV, ophthalmic, topical, intranasal, inhalation, and IM forms available; has little mineralocorticoid activity
fludrocortisone (Florinef)
PO: 0.1-0.2 mg/day
Has strong mineralocorticoid activity
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Although hypersecretion of these hormones can be due to pituitary (due to excess ACTH) or adrenal tumors, the most common cause of Cushing syndrome is long-term therapy with high doses of systemic corticosteroids. Signs and symptoms include adrenal atrophy, behavioral changes, changes in vision, osteoporosis, HTN, increased risk of infections, delayed wound healing, acne, peptic ulcers, fluid retention, weight gain, and a redistribution of fat around the face (moon face), abdomen, shoulders, and neck (buffalo hump).
CONCEPT REVIEW 33.2
* Why does administration of corticosteroids for extended periods result in adrenal atrophy?
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Prototype Drug: *** Hydrocortisone (Cortef, Hydrocortone, Others)
Therapeutic Class: Adrenal hormone replacement; drug for moderate to severe asthma and allergies, and antineo plastic therapy Pharmacologic Class: Systemic corticosteroid
Actions and Uses: Structurally identical to the natural hormone Cortisol, hydrocortisone is a synthetic corticosteroid that is the drug of choice for treating adrenocortical insufficiency. When used for replacement therapy, it is given at physiologic doses. Once proper dosing is achieved, its therapeutic effects should mimic those of natural corticosteroids. Hydrocortisone is also available for the treatment of inflammation, allergic disorders, and many other conditions. Intra-articular injections may be given to decrease severe inflammation in affected joints.
Adverse Effects and Interactions: When used at physiologic doses for replacement therapy, adverse effects of hydrocortisone should not be evident. The patient and the healthcare professional must be vigilant, however, in observing for signs of Cushing syndrome, which can develop with high doses. If taken for longer than 2 weeks, hydrocortisone should be discontinued gradually.
Hydrocortisone interacts with many drugs. For example, barbiturates, phenytoin, and rifampin may increase liver metabolism, thus decreasing hydrocortisone levels. Estrogens increase the effects of hydrocortisone. NSAIDs increase the risk of ulcers. Cholestyramine and colestipol decrease hydrocortisone absorption. Diuretics and amphotericin B increase hypokalemia. Anticholinesterase drugs may produce severe weakness. Hydrocortisone may cause a decrease in immune response to vaccines and toxoids. Patients with diabetes should be advised to check their blood glucose levels more frequently. Hydrocortisone may cause a rise in blood glucose levels, especially in patients with diabetes.
Herbal supplements, such as aloe and buckthorn (a laxative), may cause potassium deficiency.
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Nursing Process Focus Patients Receiving Systemic Corticosteroid Therapy
ASSESSMENT
PLANNING: PATIENT GOALS AND EXPECTED OUTCOMES
Prior to administration:
* Obtain a complete health history, including cardiovascular, respiratory, neurologic, renal, and liver conditions; pregnancy, allergies, drug history, and possible drug interactions.
* Evaluate laboratory blood findings: CBC, electrolytes, glucose, lipid panel, renal and liver function studies.
* Acquire the results of a complete physical examination, including vital signs, height, and weight.
* Deficient Knowledge related to a lack of information about drug therapy
* Risk for Infection related to immunosuppression
* Risk for Injury related to adverse effects of drug therapy
* Risk for Imbalanced Fluid Volume related to fluid retention properties of corticosteroids
* Risk for Electrolyte Imbalance related to adverse drug effects of drug therapy
* Risk for Unstable Blood Glucose Level related to adverse effects of drug therapy
POTENTIAL NURSING DIAGNOSES*
The patient will:
* Experience therapeutic effects (decreased signs and symptoms of inflammation or allergic response).
* Be free from or experience minimal adverse effects from drug therapy.
* Verbalize an understanding of the drug’s use, adverse effects, and required precautions.
(Continued)
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Nursing
Process Focus (continued)
IMPLEMENTATION
Interventions and (Rationales)
Patient Education/Discharge Planning
* Administer medication correctly, and evaluate the patient’s knowledge of proper administration. Do not stop drug abruptly; taper off over a 1- to 2-week period. Monitor the patient’s compliance with the drug regimen. (Improper use can cause an increase in adverse effects. Sudden discontinuation of these drugs can precipitate an adrenal insufficiency.)
Instruct*
Not stop taking corticosteroids abruptly and to notify the healthcare provider if unable to take the drug for more than 1 day. the patient to:
* Use the self-administering tapering dose pack properly.
* Take oral medications with food.
* Monitor vital signs. (Corticosteroids may cause increase in blood pressure and tachycardia because of increased blood volume and potential vasoconstriction effect.)
Instruct the patient:
* To report tachycardia, blood pressure over 140/90, dizziness, palpitations, or headaches to the healthcare provider.
* How to use blood pressure monitoring equipment properly.
* Monitor for infection. Protect the patient from potential infections. (Corticosteroids increase susceptibility to infections by suppressing the immune response.)
Instruct the patient to:
* Avoid people with infections.
* Report signs of infection: fever, cough, sore throat, joint pain, increased weakness, rash, white patches in mouth, and malaise to the healthcare provider.
* Consult with the healthcare provider before taking any immunizations.
* Monitor for symptoms of Cushing syndrome, such as moon face, “buffalo hump” contour of shoulders, weight gain, muscle wasting, and increased deposits of fat in the trunk. (Symptoms may indicate excessive use of corticosteroids.)
Instruct the patient:
* To weigh self daily.
* That initial weight gain is expected; provide the patient with weight-gain parameters that warrant reporting.
* That there are multiple adverse effects to therapy and changes in health status should be reported to the healthcare provider.
* Monitor blood glucose levels. (Corticosteroids cause an increase in glucose formation [gluconeogenesis] and a decrease in glucose utilization, causing hyperglycemia.)
Instruct the patient to:
* Report symptoms of hyperglycemia, such as excessive thirst, copious urination, and insatiable appetite to the healthcare provider.
* Adjust insulin dose based on blood glucose level, as directed by the healthcare provider.
* Monitor skin and mucous membranes for lacerations, abrasions, or breaks in integrity. (Corticosteroids impair wound healing.)
Instruct the patient to:
* Examine skin daily for cuts and scrapes and to cover any Injuries with sterile bandage.
* Watch for symptoms of skin infection such as redness, swelling, and drainage.
* Notify the healthcare provider of any nonhealing wound or symptoms of infection
* Monitor GI status for evidence of ulcers, GI bleeding. (Corticosteroids decrease gastric mucus production and predispose patients to peptic ulcers.)
Instruct the patient to:
* Report GI adverse effects such as heartburn, dizziness, abdominal pain, blood in emesis, or tarry stools to the healthcare provider.
* Take drug with food or milk to decrease GI irritation.
* Avoid or eliminate alcohol.
* Continue to monitor periodic laboratory work: CBC, electrolytes glucose, lipid panel, liver and renal function studies. (Corticosteroids can cause hypernatremia and hypokalemia.)
Instruct the patient to:
Consume a diet high in protein, calcium, and potassium but low in fat and concentrated simple carbohydrates.
* Keep all laboratory appointments.
* Monitor changes in the musculoskeletal system. (Corticosteroids decrease bone density and strength and cause muscle atrophy and weakness.)
Instruct the patient:
* That the drug may cause weakness in bones and muscles; avoid strenuous activity that may cause injury.
* To participate in weight-bearing exercise or physical activity to help maintain bone and muscle strength.
* To maintain adequate calcium in diet.
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Interventions and (Rationales)
Patient Education/Discharge Planning
* Monitor emotional status. (Corticosteroids may produce mood and behavior changes such as depression or feeling of invulnerability.)
* Instruct the patient that mood changes may be expected and to report excessive mood swings or unusual changes in mood to the healthcare provider.
* Monitor vision periodically. (Corticosteroids may cause increased intraocular pressure and an increased risk of glaucoma and cataracts.)
Inform the patient to:
* Have regular eye exams twice a year.
* Immediately report any eye pain, halos, inability to focus, or diminished or blurring vision to the healthcare provider.
* Weigh patient daily, and report increasing peripheral edema. (Dally weight is an accurate measure of fluid status.)
* Instruct the patient to weigh self daily at the same time every day and to report a gain of 2 lb (1 kg) per day or presence of or increase in edema.
EVALUATION OF OUTCOME CRITERIA
* Evaluate the effectiveness of drug therapy by confirming that patient goals and expected outcomes have been met (see “Planning”). See Table 33.4 for a list of drugs to which these nursing actions apply.
*Herdman, T.H. & Kamitsuru, S. (Eds.). Nursing Diagnoses: Definitions S Classification 2015-2017. Copyright © 2014, 1994-2014 NAN DA International. Used by arrangement by John Wiley & Sons, Inc. Companion website: www.wiley.com/go/nursingdiagnoses.
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Patients Need to Know
Patients treated for endocrine disorders need to know the following:
Regarding Hypothalamic and Pituitary Drugs
1. Patients taking GH should record height and weight weekly. Records should be brought to the healthcare provider each visit.
2. A diary of nighttime sleep habits and any bed-wetting should be kept and provided to the healthcare provider.
Regarding Thyroid Medications
3. Pulse rates should be taken regularly because they are a good Indicator of the effectiveness of thyroid medications. If the pulse rate consistently exceeds 100 or any other significant change is noted, contact the healthcare provider.
4. Because finding the correct dosage of thyroid hormone often takes several months, do not change the prescribed dose without being advised to do so by a healthcare provider.
Regarding Corticosteroids
5. When taking oral corticosteroids for more than 2 weeks, do not miss doses or discontinue the drug without consulting a healthcare provider.
6. See a healthcare provider if any infections, cuts, or injuries appear to be healing too slowly while on corticosteroids.
7. If taking hydrocortisone for replacement therapy, take the medication between 6:00 a.m. and 9:00 a.m. because this is the time when natural corticosteroids are released.
Chapter Review Core Concepts Summary
33.1 The endocrine system maintains homeostasis by using hormones as chemical messengers.
Hormones are secreted by endocrine glands in response to changes in the internal environment. The hormones act on their target cells to return the body to homeostasis. Negative feedback prevents the body from overresponding to internal changes.
33.2 The hypothalamus and the pituitary gland secrete hormones that control other endocrine organs.
The hypothalamus secretes releasing hormones that signal the anterior pituitary gland to release its hormones. Pituitary hormones travel throughout the body to affect many other organs.
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33.3 Hormones are used as replacement therapy, as antineoplastics, or as “antihormones” to block endogenous actions.
Hormones are often given as replacement therapy to patients who are not able to secrete sufficient quantities of endogenous hormones. In high doses, several hormones may be used as antineoplastics. Hormones may also be used therapeutically to block natural physiologic effects.
33.4 Of the many hypothalamic and pituitary hormones, several have clinical applications as drugs.
ADH, or vasopressin, increases water reabsorption in the kidney and is used to treat diabetes insipidus. GH, or somatotropin, is used to increase the height of children with growth hormone deficiencies.
33.5 The thyroid gland controls the basal metabolic rate and affects virtually every cell in the body.
TSH released from the pituitary gland stimulates release of thyroid hormone. The thyroid gland secretes thyroid hormone, which is essential for normal growth and development. Adequate hormone levels are necessary for infants, children, and adults. Thyroid hormone is a combination of two different hormones, thyroxine and triiodothyronine, both of which require iodine for their synthesis.
REVIEW Questions
Answer the following questions to assess your knowledge of the chapter material, and go back and review any material that is not clear to you.
1. The patient, who has been diagnosed with adrenal insufficiency, has been started on corticosteroids. The nurse explains that at high doses, and if taken for long periods of time, these drugs may cause symptoms like those seen in
1. Cushing syndrome.
2. Graves disease.
3. Diabetes insipidus.
4. Diabetes mellitus.
2. The nurse is assisting a patient with chronic adrenal insufficiency to make a medication plan for an upcoming camping trip. He is taking hydrocortisone (Cortef) and fludrocortisones (Florinef) as replacement therapy. Which detail does this patient need to remember?
1. Take his blood pressure once or twice a day.
2. Avoid crowded indoor areas to avoid infections.
3. Have his vision check before he leaves.
4. Make sure to carry extra medication in case there is a delay in getting home.
3. A patient is being treated with propylthiouracil (PTU) for hyperthyroidism while awaiting a thyroidectomy. What symptoms will the nurse tell the patient to report to the healthcare provider?
1. Tinnitus, altered taste, thickened saliva
2. Insomnia, nightmares, night sweats
33.6 Thyroid disorders may be treated by administering thyroid hormone or by decreasing the activity of the thyroid gland.
Hypothyroidism produces symptoms such as slowed body metabolism, slurred speech, bradycardia, weight gain, low body temperature, and intolerance to cold environments. Administration of thyroid hormone reverses these effects. Hyperthyroid patients exhibit the opposite symptoms. Hyperthyroidism may be treated with drugs that kill or inactivate thyroid cells.
33.7 Corticosteroids are released during periods of stress and influence carbohydrate, lipid, and protein metabolism in most cells.
The adrenal cortex secretes corticosteroids in response to stimulation by ACTH from the pituitary gland. Corticosteroids affect the metabolism of nearly every cell in the body and have potent anti-inflammatory effects.
33.8 Corticosteroids are prescribed for adrenocortical insufficiency and to dampen inflammatory and immune responses.
Corticosteroids are given to patients whose adrenal glands are unable to produce adequate amounts of these hormones and for a wide variety of other conditions. When used at high doses, oral therapy is limited because of the potential for producing Cushing syndrome and adrenal atrophy.
3. Sore throat, chills, low-grade fever
4. Dry eyes, decreased blinking, reddened conjunctiva
4. The healthcare provider ordered vasopressin 5 units subcutaneously, bid, for a patient. The pharmacy has vasopressin 20 units/mL. How many milliliters will be administered per dose?
1. 0.5 mL
2. 0.25 mL
3. 0.75 mL
4. 1 mL
5. The patient has been on methylprednisolone (Medrol) for an exacerbation of asthma. Which of the following instructions to the patient is of the highest priority?
1. “This medication may cause weight gain.”
2. “Do not stop taking this medication abruptly.”
3. “This medication can cause sleeplessness.”
4. “This medication may cause restlessness.”
6. An older adult with chronic bronchitis has been taking a low dose of dexamethasone for several months. In order to reduce the risk of osteoporosis, an adverse effect, the nurse instructs the patient to: (Select all that apply.)
1. Perform weight-bearing exercises at least three to four times a week.
2. Increase dietary intake of calcium and vitamin D enriched foods.
3. Remain sedentary except during periods of exercise.
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4. Increase fluid intake, including carbonated sodas, but avoid alcohol.
5. Participate in highly strenuous activities.
7. A patient will be started on desmopressin (DDAVP) for treatment of diabetes insipidus. Which instruction should the nurse include in the patient teaching plan?
1. Drink plenty of fluids, especially those high in calcium.
2. Avoid close contact with children or pregnant women for 1 week after administration of the drug.
3. Obtain and record your weight daily.
4. Wear a mask if around children and pregnant women.
8. The patient has been started on desmopressin (DDAVP). The nurse understands the medication is effective when the patient’s:
1. Urinary output increases.
2. Blood pressure falls below 90/60.
3. Blood sugar level is between 80 and 120 mg/dL.
4. Urinary output decreases.
9. The nurse should inform the parents of a child who has been prescribed somatropin (Humatrope) that:
1. The drug must be given by injection.
2. The drug must be given regularly to prevent mental deficiencies.
3. If the drug is given during late adolescence, it could add 6 to 8 inches to the child’s height.
4. Daily laboratory monitoring will be required during the first weeks of therapy.
10. A nurse is helping to prepare a teaching plan for a patient who will be discharged on the corticosteroid methylpred-nisolone (Medrol Dosepak) after a significant response to poison ivy. The nurse includes information about which of the following adverse effects of this medication? (Select all that apply.)
1. Tinnitus
2. Edema
3. Visual changes
4. Lower abdominal pain
5. Mood changes
CASE STUDY Questions
[Image: Mrs. Helen Brookfield.]
Remember Mrs. Brookfield, the patient introduced at the beginning of the chapter? Now read the remainder of the case study. Based on the information you have learned in this chapter, answer the questions that follow.
Mrs. Helen Brookfield is a 42-year-old mother of two children who works full time at a department store. She has been feeling very tired, gaining weight, and says she feels cold all the time. Because of this, she saw her healthcare provider several weeks ago. At that visit, the healthcare provider ordered some laboratory tests, including T3, T4, and TSH. She has returned to the office today to discuss her continuing symptoms and laboratory results. Her vital signs are 94/60, 58 (pulse), and a temperature of 97.4°F (36.3°C). Her weight has increased 30 pounds over the past 6 months, but she says that her appetite has decreased. The symptoms and laboratory results indicate that she has hypothyroidism. She is prescribed levothyroxine (Synthroid) 100 meg/day.
1. The nurse explains to Mrs. Brookfield that the adverse effects of levothyroxine (Synthroid) are: (Select all that apply.)
1. Constipation.
2. Weight gain.
3. Tachycardia.
4. Insomnia.
2. The nurse also instructs Mrs. Brookfield:
1. To take the pill in the afternoon with a high fiber snack to prevent stomach upset.
2. To eat plenty of fruits and vegetables to replace nutrients.
3. To take the dose in the morning before breakfast, as close to the same time each day as possible.
4. That the drug may be taken every other day if diarrhea occurs.
3. Mrs. Brookfield has been on levothyroxine (Synthroid) 100 meg/day. The nurse recognizes the medication is being effective when the:
1. Patient sleeps more hours per day.
2. Patient’s weight increases.
3. Patient’s pulse rate increases.
4. Patient states she feels tired.
4. A month later, Mrs. Brookfield reports feeling nervous and is having occasional palpitations and tremors. These symptoms may indicate that:
1. Mrs. Brookfield is still experiencing symptoms of hypothyroidism, and the dose may need to be increased.
2. Mrs. Brookfield’s thyroid is now functioning normally, and levothyroxine is no longer needed.
3. Mrs. Brookfield has developed diabetes and needs further evaluation.
4. Mrs. Brookfield is experiencing symptoms of hyperthyroidism, and the drug dosage needs to be decreased.
Answers and complete rationales for the Review and Case Study Questions appear in Appendix A.
REFERENCE
Herdman, T. H., & Kamitsuru, S. (Eds.). (2014). NANDA International nursing diagnoses: Definitions and classification, 2015-2017. Oxford, United Kingdom: Wiley-Blackwell
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SELECTED BIBLIOGRAPHY
Akamizu, T., Amino, N., DeGroot, L. J. (2013). Hashimoto’s thyroiditis. Retrieved from http://www.ncbi.nlm.nih.gov/books/NBK285557
Almandoz, J. R, & Gharib, H. (2012). Hypothyroidism: Etiology, diagnosis, and management. Medical Clinics of North America, 96, 203-221. doi:10.1016/j.mcna.2012.01.005
American Association of Clinical Endocrinology, (n.d.) Thyroid awareness. The thyroid and pregnancy. Retrieved from http: / / www.thyroi-dawareness.com/the-thyroid-and-pregnancy
American Thyroid Association. (2014). Postpartum thyroiditis. Retrieved from http://www.thyroid.org/wpcontent/uploads/patients/brochures/Postpartum_Thyroiditis_brochure.pdf
Baby’s First Test. (2015). About newborn screening. Screening facts. Retrieved from http://www.babysfirsttest.org/newborn-screen-ing/screening-facts
Crawford, A., & Harris, H. (2013). Tipping the scales: Understanding thyroid imbalances. Nursing Critical Care, 8(1), 23-28. doi:10.1097/01.CCN.0000418818.21604.22
Falorni, A., Minarelli, V., & Morelli, S. (2013). Therapy of adrenal insufficiency: An update. Endocrine, 43, 514-528. doi:10.1007/ S12020-012-9835-4
Fatourechi, V. (2014). Hyperthyroidism and thyrotoxicosis. In F. Bandier, H. Gharib, A. Golbert, L. Griz, & M. Faria (Eds.), Endocrinology and diabetes: A problem-oriented approach (pp. 9-21). New York, NY: Springer. doi:10.1007/978-l-4614-8684-8_2
Feelders, R. A., & Hofland, L. J. (2013). Medical treatment of Cushing’s disease. The Journal of Clinical Endocrinology & Metabolism, 98, 425-438. doi:10.1210/jc.2012-3126
Gorman, L. S. (2012). The adrenal gland: Common disease states and suspected new applications. Clinical Laboratory Science: Journal of the American Society for Medical Technology, 26(2), 118-125.
Griffing, G. T. (2015). Addison disease clinical presentation. Retrieved from http://emedicine.medscape.com/article/116467-clinical
Khardori, R. (2014). Diabetes insipidus. Retrieved from http://emedicine.medscape.com/article/117648-overview
Marieb, E. N., & Hoehn, K. (2017). Human anatomy and physiology
(10th ed.). San Francisco, CA: Benjamin Cummings.
Nguyen, H. (2015). Iatrogenic Cushing syndrome. Retrieved from
http://emedicine.medscape.com/article/117365-overview Orlander, P. R. (2015). Hypothyroidism. Retrieved from http://emedicine.medscape.com/article/122393-overview Skugor, M. (2014). Hypothyroidism and hyperthyroidism. Retrieved from http://www.clevelandclinicmeded.com/medicalpubs/ diseasemanagement/ endocrinology/hypo thyroid ism-and-hyperthyroidism
Silverthorn, D. U. (2016). Human physiology: An integrated approach (7th ed.). San Francisco, CA: Benjamin Cummings.
The New York Times, (n.d.). Chronic thyroiditis (Hashimoto’s disease) in-depth report. Retrieved from http://www.nytimes.com/health/ guides/disease/chronic-thyroiditis-hashimotos-disease/print, html
Toft, D. (2014). Graves’ disease overview. What is Graves’ disease? Retrieved from http://www.endocrineweb.com/conditions/graves-disease / graves-disease-overview University of Maryland Medical Center. (2012). Hypothyroidism.
Retrieved from http://umm.edu/health/medical/reports/articles / hypothyroidism
Vellanki, P. (n.d.). Hypothyroidism: Potential symptoms and causes of an underactive thyroid gland. Retrieved from http://www.endocrineweb.com/conditions/hypothyroidism/hypothyroidism-potential-symptoms-causes-underactive-thyroid-gland
Womens Health Advice.com (n.d.). Thyroid cancers. Retrieved from http://www.womens-health-advice.com/thyroid/cancer.html
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Chapter 34 Drugs for Diabetes Mellitus
[Image: Mr. Brian Jones.]
“I’ve always felt okay but recently I’ve been feeling sluggish. Now I learn that my sugar levels are high.”
Mr. Brian Jones
Core Concepts Drug Snapshot
34.1 The pancreas is responsible for the regulation of blood glucose levels.
34.2 Type 1 diabetes is caused by a deficiency of insulin.
34.3 Insulin replacement therapy is required for type 1 diabetes.
34.4 Type 2 diabetes is the most common form of the disorder.
34.5 Antidiabetic drugs are prescribed after diet and exercise have failed to reduce blood glucose to normal levels.
Drug Snapshot
The following drugs are discussed in this chapter:
Drug Classes
Prototype Drugs j
Insulin
***regular insulin (Humulin R, Novolin R)
Antidiabetic drugs for type
2 diabetes
*** metformin (Fortamet,
Glucophage, Glumetza, others)
Learning Outcomes
After reading this chapter, the student should be able to:
1. Explain how blood glucose levels rise and fall and are stabilized with insulin and glucagon.
2. Explain the cause of type 1 diabetes mellitus.
3. Identify representative types of insulin, and explain their mechanisms of drug action, primary actions, and important adverse effects.
4. Explain the cause of type 2 diabetes mellitus.
5. Identify the representative drug classes used to treat type 2 diabetes mellitus, and explain their mechanisms of drug action, primary actions, and important adverse effects.
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exo = out/away from
crine = to secrete
endo = within
gluco = glucose
hypo = lowered
glyc = sugar
ernie = blood
FIGURE 34.1 Microscopic view of glucagon- and insulin-secreting cells in the islets of Langerhans
Key Terms
diabetic ketoacidosis (DKA) (KEY-toe-assi-doh-sis)
glucagon (GLUE-kah-gon)
hyperglycemic effect (hi-pur-gli-SEEM-ik)
hypoglycemic effect (hi-po-gli-SEEM-ik)
incretin mimetics
incretins
incretin enhancers (in KREE tin)
insulin (IN-sule-in)
insulin analogs (ANNAH-logs)
insulin resistance
islets of Langerhans (EYE-lits of
LANG-gur-hans)
ketoacids (KEY-toe-ass-ids)
type 1 diabetes mellitus (die-uh-BEE tees MEL-uh-tiss)
type 2 diabetes mellitus
Diabetes is one of the leading hormone disorders in the United States. Mortality due to diabetes has been steadily increasing, causing concern among public health officials and the general public. Diabetes can lead to serious complications, including heart disease, stroke, blindness, kidney failure, and amputations. Since healthcare providers frequently care for patients with diabetes, it is imperative that its treatment and possible complications are well understood.
Core Concept 34.1***
The pancreas is responsible for the regulation of blood glucose levels.
Located behind the stomach and between the duodenum and spleen, the pancreas is an organ that is essential to the function of both the digestive and the endocrine systems. It is responsible for the secretion of enzymes that assist in the chemical digestion of nutrients in the duodenum. This is the exocrine function of the pancreas. Clusters of cells in the pancreas, called islets of Langerhans, are responsible for the secretion of the hormones glucagon and insulin. This is the pancreas’s endocrine function (Figure 34.1).
Glucose is one of the body’s most essential molecules. The body prefers to use glucose as its primary energy source: The brain relies almost exclusively on glucose for its energy needs. Because of this need, blood levels of glucose must remain relatively constant throughout the day. Although many factors contribute to maintaining a stable blood glucose level, the two pancreatic hormones play major roles: Insulin acts to decrease blood glucose levels, and glucagon acts to increase blood glucose levels (Figure 34.2).
Following a meal, the pancreas recognizes the rising blood glucose level and releases insulin. Without insulin, glucose stays in the bloodstream and is not able to enter cells of the body. Cells may be virtually surrounded by glucose but they are unable to use it until insulin arrives. Insulin acts like a gateway for the entry of glucose into the cell. Thus, insulin is said to have a hypoglycemic effect, because its presence causes glucose to leave the bloodstream, and therefore blood glucose falls. Some of the glucose is stored as glycogen in the liver, where it can be converted back to glucose between meals.
The pancreas also secretes glucagon, which has the opposite effect of insulin. When levels of blood glucose fall, glucagon is secreted. Glucagon’s primary function is to maintain adequate blood levels of glucose between meals.
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FIGURE 34.2 Insulin, glucagon, and blood glucose levels.
Glucagon increases blood glucose levels by increasing the breakdown of glycogen into glucose. Decreasing glycogen synthesis enhances the synthesis of glucose. Thus, glucagon has a hyperglycemic effect, because it causes glucose in the bloodstream to rise. The physiological actions of glucagon are essentially opposite of insulin.
TYPE 1 DIABETES MELLITUS *** Core Concept 34. Type 1 diabetes is caused by a deficiency of insulin.
Diabetes mellitus (DM) is a metabolic disorder in which there is deficient insulin secretion or decreased sensitivity of insulin receptors on target cells. Without insulin present, glucose is prevented from entering the cells and builds to high levels in the blood; thus, hyperglycemia is the hallmark characteristic of DM. The causes of DM include a combination of genetic and environmental factors. The recent increase in the frequency of the disease is probably the result of trends toward more inactive and stressful lifestyles and increasing consumption of foods with higher calories. Prediabetes is a condition in which blood glucose levels are higher than normal but not high enough to be classified as diabetes. According to the International Diabetes Federation, diabetes and obesity are among the biggest public health challenges of the 21st century.
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Fast Facts Diabetes Mellitus
* Over 29 million Americans or 9.3% of the population have diabetes. Millions of people are unaware that they have the disease.
* It is estimated that 12 million women aged 20 years and older have diabetes, and approximately 27 million have prediabetes.
* Gestational diabetes affects about 2% to 10% of all pregnant women in the United States each year.
* Diabetes is the seventh leading cause of death; the risk of death among people with diabetes is twice that of people of similar age without diabetes.
* Diabetes is a major cause of retinopathy leading to blindness in adults.
* Diabetes is responsible for about 60% of nontraumatic lower-limb amputations; over 73,000 amputations are performed each year on patients with diabetes.
Source: Based on Centers for Disease Control and Prevention. (2014). 2014 Diabetes National Statistics Report; Centers for Disease Control and Prevention, (n.d.). Women at High Risk for Diabetes: Physical Activity, Healthy Eating, and Weight Loss; Centers for Disease Control and Prevention. (2014) National Diabetes Statistics Report: Estimates of Diabetes and Its Burden in the United States.
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dia = through (e.g., siphon)
betes = to go
mellitus = sweet
poly = excessive
phagia = hunger
dipsia = thirst
glucos = glucose
uria = urination
keto = ketone chemical compound (e.g., acetone)
acids/acidosis = state of lowered pH
Type 1 diabetes mellitus is one of the most common diseases of childhood. Type 1 DM was previously called juvenile-onset diabetes. It is often diagnosed in children between the ages of 11 and 13. Because approximately one-fourth of patients with type 1 DM develop the disease in adulthood, this is not the most accurate name for this disorder. This type of diabetes is also sometimes referred to as insulin-dependent diabetes mellitus because with this disorder the pancreas does not produce insulin.
The signs and symptoms of type 1 DM are consistent from patient to patient. The typical signs and symptoms are fasting blood glucose greater than 126 mg/dL on at least two separate occasions, polyuria (excessive urination), polyphagia (increased hunger), polydipsia (increased thirst), glucosuria (high levels of glucose in the urine), weight loss, and fatigue.
When glucose is unable to enter cells, lipids are used as the primary energy source and ketoacids are produced as waste products. These ketoacids can give the patient’s breath an acetone-like, fruity odor. More importantly, high levels of ketoacids lower the pH of the blood, causing diabetic ketoacidosis (DKA). Untreated DM produces long-term damage to arteries, which leads to heart disease, stroke, kidney disease, and blindness. Lack of adequate circulation to the feet may cause death of tissues leading to gangrene of the toes, requiring amputation. Nerve degeneration, or neuropathy, is common, with symptoms ranging from tingling in the fingers or toes to complete loss of sensation of a limb.
Core Concept 34.3*** Insulin replacement therapy is required for type 1 diabetes.
Patients with type 1 DM are severely deficient in insulin production; thus, insulin replacement therapy is required in normal physiological amounts. Insulin is also required for those with type 2 diabetes who are unable to manage their blood glucose levels with diet, exercise, and antidiabetic drugs.
Because normal insulin secretion varies greatly in response to daily activities such as eating and exercise, glucose monitoring and insulin administration must be carefully planned along with proper meal planning and lifestyle habits. The desired outcome of insulin therapy is to prevent the long-term consequences of the disorder by strictly maintaining blood glucose levels within the normal range. Poor compliance (not properly monitoring glucose levels or skipping insulin injections) can lead to continuing hyperglycemia and even death. Illness and stress can also cause an increase in blood glucose levels.
Many types of insulin are available, differing in their source, time of onset and peak effect, and duration of action. Almost all insulin today is human insulin obtained through recombinant DNA technology. Pharmacologists have modified human insulin to create forms that have a more rapid onset of action or a more prolonged duration of action. These modified forms are called insulin analogs. All the different types of insulin are administered by the subcutaneous route and are listed in Table 34.1.
Table 34.1 Types of Insulin: Actions and Administration
insulin aspart (NovoLog)
Rapid
15 minutes
1-3 hours
3-5 hours
Subcutaneous; 5-10 minutes before a meal
insulin lispro (Humalog)
Rapid
5-15 minutes
0.5-1 hours
3-4 hours
Subcutaneous; 5-10 minutes before a meal
insulin glulisine (Apidra)
Rapid
15-30 minutes
1 hours
3-4 hours
Subcutaneous; 15 minutes before a meal or within 20 minutes after starting a meal
***insulin regular (Humulin R, Novolin R)
Short
30-60 minutes
2-4 hours
5-7 hours
Subcutaneous; 30-60 minutes before a meal; IV in emergencies
insulin isophane (NPH, Humulin N, Novolin N, ReliOn N)
Intermediate
1-2 hours
4-12 hours
18-24 hours
Subcutaneous; 30 minutes before first meal of the day and 30 minutes before evening meal, if necessary
insulin detemir (Levemir)
Long
Gradual: over 24 hours
6-8 hours
To 24 hours
Subcutaneous; with evening meal or at bedtime
insulin glargine (Lantus)
Long
Gradual: over 24 hours
N/A
To 24 hours
Subcutaneous; once daily, given at the same time each day
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Doses of insulin are highly individualized for the precise control of blood glucose levels in each patient. Some patients require two or more injections daily for proper diabetes management. If mixing insulin, such as rapid- or short-acting with an intermediate-acting, the rapid or short-acting insulin is always drawn into the syringe first. For ease of administration, some of these combinations are marketed in cartridges containing premixed solutions. Important, however, is the fact that onset, peak, and duration times for each insulin are different within the same medication injection:
* Humulin 70/30 and Novolin 70/30: contain 70% NPH insulin and 30% regular insulin.
* Humulin 50/50: contains 50% NPH insulin and 50% regular insulin.
* NovoLog Mix 70/30: contains 70% insulin aspart protamine and 30%) insulin aspart.
* Humalog Mix 75/25: contains 75% insulin lispro protamine and 25% insulin lispro.
Some patients may have an insulin pump (Figure 34.3). This pump is usually abdominally anchored and is programmed to release small subcutaneous doses of insulin into the abdomen at predetermined intervals, with larger amounts administered manually at mealtime if necessary. Most pumps contain an alarm that sounds to remind patients to take their insulin.
Adverse effects of insulin may include allergic reactions, redness at the site of injection, and changes in fat tissue (lipodystrophy) in the areas of body where injections are given more frequently. However, the most common adverse effect of insulin therapy is overtreatment –when insulin removes too much glucose from the blood, resulting in hypoglycemia. This occurs when a patient with type 1 diabetes has more insulin in the blood than is needed to balance the amount of glucose in the blood. Hypoglycemia may occur when insulin levels peak; during exercise, stress, or illness; when the patient receives too much insulin due to medication error; or if the patient skips a meal. Signs and symptoms of hypoglycemia include the sudden onset of pale, cool, and moist skin; confusion; mild tremors; and dizziness, usually with blood glucose of less than 50 mg/dL.
Giving food or drinks containing glucose (sugar) can reverse mild to moderate hypoglycemia symptoms. Patients are encouraged to routinely carry candy or other readily absorbable carbohydrates, such as crackers, to take at the first signs of a drop in blood glucose. For serious hypoglycemia, glucose can be administered via the IV route. In addition, the hormone glucagon is also used in emergency treatment. Glucagon can be administered IV, IM, or subcutaneously. Unstable diabetics can carry a glucagon pen for emergency use as well.
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New Drug Focus WILL GLUCAGON NASAL SPRAY REPLACE GLUCAGON INJECTIONS?
Families often fear what will happen if their diabetic loved one takes too much insulin. If not properly monitored, insulin can lower blood sugar to an unsafe level, and the patient risks becoming unresponsive or unconscious. Until recently, in an emergency situation, the only way to quickly raise blood glucose levels was to either have access to an emergency injection kit or take immediate action like drinking or ingesting something sweet. With intranasal glucagon, emergency treatment will be much easier to accomplish. Patients or caregivers will not have to mix or reconstitute vials of powder. Even if a patient is unable to self-administer, one-step glucagon nasal spray can raise blood sugar levels up to 200 mg/dL within 10 minutes. This product has already completed Phase III clinical trials, and U.S. Food and Drug Administration (FDA) approval is expected in 2016.
FIGURE 34.3 Insulin pump programmed to release insulin at predetermined intervals throughout the day.
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Prototype Drug: *** Regular Insulin (Humulin R, Novolin R)
Therapeutic Class: Drug for diabetes mellitus Pharmacologic Class: Hypoglycemic drug
Actions and Uses: Regular insulin is prepared as human insulin through recombinant DNA technology. It is classified as short-acting insulin, with an onset of action of 30 to 60 minutes, a peak effect at 2 to 3 hours, and a duration of 5 to 7 hours. Its primary action Is to promote the entry of glucose into cells. For the emergency treatment of acute ketoacidosis, it may be given subcutaneously or IV. Regular insulin is also available as Humulin 70/30 (a mixture of 30% regular insulin and 70% isophane insulin) or as Humulin 50/50 (a mixture of 50% of both regular and isophane insulin).
Adverse Effects and Interactions: The most serious adverse effect from insulin therapy is hypoglycemia. Hypoglycemia may result from taking too much insulin, not properly timing the Insulin injection with food intake, or skipping a meal. Dietary carbohydrates must be in the blood when insulin is injected; otherwise the drug will remove too much glucose, and signs of hypoglycemia –tachycardia, confusion, sweating, and drowsiness –will result. If severe hypoglycemia is not quickly treated with glucose, convulsions, coma, and death may follow.
Regular insulin interacts with many drugs. For example, the following substances may increase hypoglycemic effects: alcohol, salicylates, monoamine oxidase inhibitors (MAOIs), and anabolic steroids. The following substances may decrease hypoglycemic effects: corticosteroids, thyroid hormones, and epinephrine. Serum glucose levels may be increased with furo-semide or thiazide diuretics. Symptoms of hypoglycemic reaction may be hidden if beta blockers are used at the same time.
Use cautiously with herbal supplements such as garlic and ginseng, which may increase the hypoglycemic effects of insulin.
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Nursing Process Focus Patients Receiving Insulin Therapy
ASSESSMENT
POTENTIAL NURSING DIAGNOSES*
Prior to administration:
* Obtain a complete health history, including cardiovascular, vision, skin, neurologic, renal, and liver conditions; allergies; drug history; and possible drug Interactions.
* Evaluate laboratory blood findings: complete blood count (CBC), electrolytes, lipid panel, liver and renal function studies, glucose, and glucated hemoglobin (HbA1C).
* Acquire the results of a complete physical examination, including vital signs, height, and weight; presence of paresthesia of hands or feet; ulceration of lower extremities; and condition of skin at insulin injection sites.
* Obtain a dietary history, including type of foods eaten, caloric intake, number of meals and snacks, and fluid types.
* Determine knowledge of diabetic medications, adverse effects, self-administration, and blood glucose monitoring.
Deficient Knowledge related to a lack of information about the disease process, medications, and need for lifestyle changes
* Ineffective Health Management related to noncompliance with medication regimen, presence of adverse effects, and lifelong need for medication
* Noncompliance related to the complexity of the medication regimen, lifestyle changes, and adverse effects of drug therapy
* Risk for Unstable Blood Glucose Level related to lack of diabetes management, unhealthy diet, inadequate glucose monitoring, or improper use of medication
* Risk for Injury related to blood glucose elevations, impaired circulation, or adverse effects of drug therapy
* Risk for Imbalanced Nutrition related to disease process and adverse effects of drug therapy
* Risk for Infection related to blood glucose elevations and impaired circulation
PLANNING: PATIENT GOALS AND EXPECTED OUTCOMES
The patient will:
* Experience therapeutic effects (stable blood glucose levels).
* Be free from or experience minimal adverse effects from drug therapy.
* Verbalize an understanding of the drug’s use, adverse effects, and required precautions.
* Demonstrate an understanding of lifestyle modifications necessary for successful maintenance of drug therapy.
IMPLEMENTATION
Interventions and (Rationales)
Patient Education/Discharge Planning
* Monitor blood glucose several times a day, usually before meals. Hold or provide insulin per healthcare provider’s protocols. (Daily glucose levels will assist in maintaining stable blood glucose.)
* Instruct the patient how to monitor blood glucose, Including use of equipment, and when to notify the healthcare provider.
* Administer insulin as prescribed, at meal or insulin peak times. In addition, evaluate the patient’s knowledge of proper administration. (Administering insulin at meal or peak times will assist in maintaining stable blood glucose levels.)
Inform patient or caregivers:
* Of proper administration techniques for the type of insulin ordered. Have the patient communicate understanding of how the insulin medication should be administered to keep glucose levels stable.
* That peak insulin levels and proper food sources are needed to prevent both hyper and hypoglycemia.
* Of the need to rotate insulin injection sites on a weekly basis to prevent tissue damage.
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IMPLEMENTATION
* Ensure dietary needs are met based on weight and current glucose levels. Consult with a dietitian as needed (Adequate caloric amounts of carbohydrates, proteins, and fats influence the amount of insulin needed for glucose control).
* Advise the patient to monitor food choices and follow the recommended diet plan
* Provide written materials on dietary recommendations for future reference.
* Increase frequency of blood glucose monitoring if the patient is experiencing fever, nausea, vomiting, or diarrhea. (Illness usually requires adjustments in insulin doses.)
Instruct the patient to:
* Increase blood glucose monitoring when experiencing fever, nausea, vomiting, or diarrhea.
* Notify the healthcare provider if unable to eat normal meals for a possible change in insulin dose.
* Continue to monitor periodic laboratory work: CBC, electrolytes, glucose, HbA1C, lipid profile, liver and renal function studies. (Insulin can cause potassium to move into the cell and may cause hypokalemia. Periodic monitoring assists in determining glucose control, need for medication changes, and any indicators of complications.)
Inform the patient:
* About the need to keep laboratory appointments.
* To report to the healthcare provider the first sign of heart irregularity.
* Monitor weight on a routine basis. (Changes in weight will alter insulin needs.)
* Instruct the patient to weigh self on a routine basis at the same time each day and to report to the healthcare provider any significant changes (e.g., plus or minus 10 lb [5 kg]).
* Monitor vital signs. (Increased pulse and blood pressure are early signs of hypoglycemia. Patients with diabetes may have circulatory problems or Impaired kidney function that can increase blood pressure.)
* Ensure that the patient knows how to take blood pressure and pulse and to report significant changes.
* Check for signs of hypoglycemia, especially around the time of insulin peak activity. If symptoms occur, provide quick-acting carbohydrate source (juice or simple sugar), and then recheck blood glucose. (Taking a simple sugar will raise blood sugar immediately.)
Advise the patient:
* To always carry a quick-acting carbohydrate source in case symptoms of hypoglycemia occur.
* If unsure whether symptoms are hypo or hyper, treat as hypoglycemia, wait 10-15 minutes, then check glucose level.
* If symptoms are not relieved or glucose is below 70 mg/dL, notify the healthcare provider.
* Encourage the patient to increase physical activity gradually but continue to monitor blood glucose level before and after exercise. (Exercise assists muscle cells to use glucose more efficiently, lowering blood glucose. Effects may last up to 48 hours after activity, increasing the risk of hypoglycemia.)
Inform the patient:
* About the benefit of exercise.
* To check blood glucose before and after exercise and to keep a simple sugar on his or her person while exercising.
* To eat some form of simple sugar or complex carbohydrate before strenuous exercise as prophylaxis against hypoglycemia.
* Inform the patient about proper storage of insulin.
* Ensure the proper storage of insulin to maintain potency. Opened vials may be stored at room temperature for up to 1 month, avoiding direct sunlight and heat. Store unopened vials in refrigerator. Discard any vial if any changes In solution are noted or if insulin has expired.
EVALUATION OF OUTCOME CRITERIA
Evaluate the effectiveness of drug therapy by confirming that patient goals and expected outcomes have been met (see “Planning”). See Table 34.1 for a list of drugs to which these nursing actions apply.
*Herdman. T.H. & Kamitsuru, S. (Eds.), Nursing Diagnoses: Definitions & Classification 2015-2017. Copyright © 2014, 1994-2014 NAN DA International. Used by arrangement by John Wiley & Sons, Inc. Companion website: www.wiley.com/go/nursingdiagnoses.
TYPE 2 DIABETES MELLITUS *** Core Concept 34.4 Type 2 diabetes is the most common form of the disorder.
Type 2 diabetes mellitus is the more common form of the disorder. Because type 2 DM first appeared in middle-aged adults, it has been referred to as adult-onset diabetes or maturity-onset diabetes. These are inaccurate descriptions, however, because increasing numbers of children are being diagnosed with type 2 DM. Type 2 is more common in patients who are overweight and those with low HDL-cholesterol and high triglyceride levels. Patients with type 2 DM are often asymptomatic and may have the condition for years before their diagnosis.
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asymptomatic = without having symptoms
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incretin = gut-derived
Unlike patients with type 1 diabetes, some patients with type 2 are capable of secreting insulin, although in amounts that are too small. However, the fundamental problem in type 2 is that insulin receptors in the target tissues have become unresponsive to the hormone, a phenomenon called insulin resistance. Essentially, the pancreas produces sufficient amounts of insulin, but target cells do not recognize it. In addition, the liver increases its production of glucose, compounding the problem of hyperglycemia. Whereas patients with type 1 diabetes must take insulin, those with type 2 diabetes are usually controlled with antidiabetic drugs. In severe, unresponsive cases, insulin may also be necessary for patients with type 2 diabetes.
With aging, cells become more resistant to insulin, blood glucose levels rise, and the pancreas responds by secreting even more insulin. Eventually, the hypersecretion of insulin causes beta cell exhaustion and ultimately leads to beta cell death. As type 2 DM progresses, it becomes a disorder characterized by insufficient insulin levels as well as insulin resistance. The long-term consequences of untreated type 1 and type 2 diabetes are the same.
The activity of insulin receptors can be increased by physical exercise and lowering the level of circulating insulin. In fact, adhering to a healthy diet and a regular exercise program has been shown to reverse insulin resistance and delay or prevent the development of type 2 DM. Many patients with type 2 diabetes are obese and need a medically supervised plan to help them reduce weight gradually and exercise safely. These are important lifestyle changes for such patients; they will need to maintain these changes for the remainder of their lives.
Core Concept 34.5***
Antidiabetic drugs are prescribed after diet and exercise have failed to reduce blood glucose to normal levels.
Type 2 DM is usually controlled with noninsulin antidiabetic drugs. These drugs are sometimes referred to as oral hypoglycemic drugs but this is an inaccurate name because some are given by the subcutaneous route and some do not cause hypoglycemia.
The primary groups of antidiabetic drugs for type 2 DM are classified by their chemical structures and their mechanisms of action. These include alpha-glucosidase inhibitors, big- uanides, incretin enhancers, meglitinides, sulfonylureas, and thiazolidinediones (or glitazones). Therapy with type 2 antidiabetic drugs is not effective for persons with type 1 DM. Antidiabetic drugs for type 2 DM are listed in Table 34.2.
Table 34.2 Antidiabetic Drugs for Type 2 Diabetes
Drug
Route and Adult Dose
Drug Class Remarks
ALPHA-GLUCOSIDASE INHIBITORS
acarbose (Precose)
PO: 25-100 mg tid (max: 300 mg/day)
These drugs block an intestinal enzyme that breaks down complex carbohydrates into simple sugars. Avoid use in patients with chronic intestinal diseases; use cautiously in patients with renal impairment.
miglitol (Glyset)
PO: 25-100 mg tid (max: 300 mg/day)
BIGUANIDE
***Metformin
Immediate release (Glucophage, Riomet) Extended release (Fortamet, Glucophage XR, Glumetza)
PO: 500 mg bid or 850 mg once daily; increase to 1000-2550 mg in divided doses per day (max: 2.55 g/day) Fortamet: 1000 mg once daily (max: 2.5 g/day) Glumetza: 1000-2000 mg once dally (max: 2 g/day) Glucophage XR: 500 mg once daily (max: 2 g/day)
Immediate-release forms and extended-release forms are available. Lactic acidosis is a potential complication with this medication.
INCRETIN MIMETICS (GLP-1 AGONISTS)
albiglutide (Tanzeum)
Subcutaneous: 30-50 mg once weekly
These drugs target a chemical called glucagon-like peptide (GLP). Insulin release is stimulated and glucagon release is inhibited. Nausea, diarrhea, headaches, and dizziness are common symptoms due to falling blood glucose levels. These drugs decrease appetite and promote weight loss. They should be taken or injected prior to meals.
exenatide (Byetta)
Subcutaneous: 5-10 meg one to two times per day 60 minutes prior to a meal
dulaglutide (Trulicity)
Subcutaneous: 0.75-1.5 mg once weekly
liraglutide (Victoza)
Subcutaneous: 0.6-1.8 mg once daily
INCRETIN ENHANCERS (DPP-4 INHIBITORS)
alogliptin (Nesina)
PO: 25 mg once daily
These drugs prevent the breakdown of natural incretins, allowing the hormone levels to rise and produce a greater antidiabetic response.
linagliptin (Tradjenta)
PO: 5 mg once daily
saxagliptin (Onglyza)
PO: 2.5-5 mg once daily
sitagliptin (Januvia)
PO: 100 mg once daily
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Drug
Route and Adult Dose
Drug Class Remarks
MEGLITINIDES
nateglinide (Starlix)
PO: 60-120 mg tid
These drugs stimulate the release of insulin from pancreatic islet cells similar to sulfonylurea drugs.
repaglinide (Prandin)
PO: 0.5-4 mg bid-qid (max: 16 mg/day)
SODIUM-GLUCOSE CO-TRANSPORTER (SGLT) INHIBITOR
canagliflozin (Invokana)
PO: 100 mg once daily (300 mg/day) taken before first meal
These drugs block the action of SGLT2, an enzyme in the kidney tubule causing glucose to be reabsorbed from kidney filtrate. Blocking of this co-transporter enzyme leads to more glucose being excreted in the urine. Drugs in this class have been under review by the FDA due to increased risk of bone fractures and decreased bone density in some patients.
dapagliflozin (Farxiga)
PO: 5-10 mg once daily in the morning with or without food
empagliflozin (Jardiance)
PO: 10-25 mg once daily in the morning with or without food
SULFONYLUREAS, FIRST GENERATION
chlorpropamide (Diabinese)
PO: 100-250 mg/day (max: 750 mg/day)
These drugs stimulate the release of insulin from pancreatic islet cells. Symptoms are hypoglycemia, weight gain, GI distress, and liver toxicity.
tolazamide (Tolinase)
PO: 100-500 mg one to two times per day (max: 1 g/day)
tolbutamide (Orinase)
PO: 250-1500 mg one to two times per day (max: 3 g/day)
SULFONYLUREAS, SECOND GENERATION
glimepiride (Amaryl)
PO: 1-4 mg/day (max: 8 mg/day)
Adverse effects are similar to first-generation sulfonylureas except that there are fewer drug-drug interactions. These drugs should be taken 30 minutes before breakfast.
glipizide (Glucotrol)
PO: 2.5-20 mg one to two times per day (max: 40 mg/day)
glyburide (DiaBeta, Micronase)
PO: 1.25-10 mg one to two times per day (max: 20 mg/day)
glyburide micronized (Glynase)
PO: 0.75-12 mg one to two times per day (max: 12 mg/day)
THIAZOLIDINEDIONES
pioglitazone (Actos)
PO: 15-30 mg/day (max: 45 mg/day)
These drugs have been under review by the FDA due to the increased risk of heart failure with drugs in this class.
rosiglitazone (Avandia)
PO: 2-4 mg one to two times per day (max: 8 mg/day)
MISCELLANEOUS DRUGS
bromocriptine (Cycloset)
PO: 0.8-4.8 mg/day upon awakening
Approved for Parkinson disease, pituitary adenoma, acromegaly, and women with amenorrhea and infertility caused by inappropriate augmentation of prolactin secretion.
colesevelam (Welchol)
PO: 1.875 g (3 tablets) every 12 h or 3.75 g (6 tablets) once daily
Used along with diet, exercise, and efforts to lose weight and reduce cholesterol in the bloodstream
The alpha-glucosidase inhibitors, which include acarbose (Precose) and miglitol (Glyset), act by blocking enzymes in the small intestine that are responsible for breaking down complex carbohydrates into monosaccharides. Because carbohydrates must be in the monosaccharide form to be absorbed, digestion of glucose is delayed.
Metformin (Glucophage) is the only drug in the biguanide drug class. Combinations of drugs with metformin have been developed to maximize the therapeutic effects and minimize adverse effects. Examples of selected drug combinations are: ACTOplus (pioglitazone+metformin); Avandamet (rosiglitazone+metformin); Glucovance (glyburide+ metformin); Janumet (sitagliptin+metformin); Jentadueto (linagliptin+metformin); Metaglip (glipi ide+metformin); and PrandiMet (repaglinide+metformin)
Several antidiabetic drugs act by mimicking or enhancing the effect of incretins within the GI tract. Incretins are hormones secreted by the mucosa of the small intestine following a meal, when blood glucose is elevated. Incretins signal the pancreas to increase insulin secretion and the liver to stop producing glucagon. Both of these actions lower blood glucose levels. In addition, these drugs decrease food intake by increasing the feeling of satiety (fullness), and they also delay gastric emptying, which slows glucose absorption.
Albiglutide (Tanzeum), exenatide (Byetta, Bydureon), and liraglutide (Victoza) are injectable drugs that mimic the effects of incretins. Thus, these drugs are called incretin mimetics. They accomplish their actions by activating a receptor called GLP-1. Activation of the GLP-1 receptor causes the same types of effects as the natural incretin hormone.
[sidebar]
hypox = lowered oxygen
emia = blood levels
satiety = state of fullness
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Prototype Drug:*** Metformin (Fortamet, Glucophage, Glumetza, Others)
Therapeutic Class: Antidiabetic drug Pharmacologic Class: Hypoglycemic drug; biguanide
Actions and Uses: Metformin is a preferred antidiabetic drug for managing type 2 DM because of its effectiveness and safety. It is used alone or in combination with other oral hypoglycemics or insulin. It is approved for use in children age 10 or above in immediate release and extended-release forms.
Metformin reduces glucose levels by decreasing the hepatic production of glucose and reducing insulin resistance. It does not promote insulin release from the pancreas. A major advantage of the drug is that it does not cause hypoglycemia. The drug’s actions do not depend on stimulating insulin release, so it is able to lower glucose levels in patients who no longer secrete insulin. In addition to lowering blood glucose levels, it lowers triglyceride and total and low-density lipoprotein (LDL) cholesterol levels, and it promotes weight loss.
Metformin is used off-label to treat women with polycystic ovary syndrome. Women with this syndrome have insulin resistance and high serum insulin levels.
Adverse Effects and Interactions: The most common adverse effects are GI related and include nausea, vomiting, abdominal discomfort, metallic taste, diarrhea, and anorexia. It may also cause headache, dizziness, agitation, and fatigue. Unlike the sulfonylureas, metformin rarely causes hypoglycemia or weight gain.
Metformin is contraindicated in patients with impaired renal function. It is also contraindicated in patients with heart failure, liver failure, history of lactic acidosis, or concurrent serious infection. It is contraindicated for 2 days prior to and 2 days after receiving IV radiographic contrast.
Alcohol Increases the risk for lactic acidosis. Captopril, furosemide, and nifedipine may increase the risk for hypoglycemia. The following drugs may decrease renal excretion of metformin: amiloride, cimetidine, digoxin, dofetilide, midodrine, morphine, procainamide, quinidine, ranitidine, triamterene, trimethoprim, and vancomycin. Acarbose may decrease blood levels of metformin. Use with other antidiabetic drugs potentiates hypoglycemic effects. Metformin decreases the absorption of vitamin B12 and folic acid. Garlic and ginseng may increase hypoglycemic effects.
BLACK BOX WARNING:
Lactic acidosis is a rare, though potentially fatal, adverse effect of metformin therapy. The risk for lactic acidosis is increased in patients with renal insufficiency or any condition that puts them at risk for increased lactic acid production, such as liver disease, severe infection, excessive alcohol intake, shock, or hypoxemia.
The second group of drugs, incretin enhancers, are the dipeptidyl peptidase-4 (DPP-4) inhibitors. Alogliptin (Nesina), linagliptin (Tradjenta), saxagliptin (Onglyza), and sitagliptin (Januvia) prevent the breakdown of natural incretins, allowing the hormone levels to rise and produce a greater response. These drugs are given orally and are effective at lowering blood glucose with few adverse effects. They work well with other antidiabetic drugs and do not cause hypoglycemia.
The meglitinides, repaglinide (Prandin) and nateglinide (Starlix), act by stimulating the release of insulin from the pancreas in a manner similar to that of the sulfonylureas. Both drugs in this class have short durations of action of 2 to 4 hours, and they are well tolerated.
In 2013, the FDA approved canagliflozin (Invokana), the first in a new class of drugs called the sodium-glucose co-transporter (SGLT) inhibitors. Inhibiting the SGLT2 receptor in the kidney allows more glucose to leave the blood and be excreted via the urine. This drug has the advantage of promoting weight loss. Two additional drugs in this class, dapa-gliflozin (Farxiga) and empagliflozin, were approved in 2014 and have very similar actions and adverse effects. Recently approved fixed dose combinations include Invokamet (metformin with canagliflozin) and Xigduo XR (metformin with and dapagliflozin).
The first oral hypoglycemics available, sulfonylureas are divided into first- and second-generation categories. Although drugs from both generations are equally effective at lowering blood glucose, the second-generation drugs exhibit fewer drug-drug interactions. The sulfonylureas act by stimulating the release of insulin from pancreatic islet cells and by increasing the sensitivity of insulin receptors on target cells.
The thiazolidinediones, or glitazones, reduce blood glucose by decreasing insulin resistance and by inhibiting hepatic production of glucose. Optimal lowering of blood glucose may take 3 to 4 months of therapy. Liver function should be monitored, because thiazolidinediones may be hepatotoxic. Drugs in this class contain black box warnings. In 2013, an FDA panel of experts voted to modify or remove measures that limited patient access to rosiglitazone. Under the FDA’s risk-evaluation management strategy (REMS), this drug remains under close scrutiny due to the risk of fluid retention and heart problems observed in some patients.
Two other miscellaneous drugs include bromocriptine and colesevelam. Bromocriptine was originally approved to treat Parkinson disease, pituitary adenoma, acromegaly, and amenorrhea and infertility in women caused by excessive prolactin secretion. The drug acts on the central nervous system to increase levels of the neurotransmitter dopamine.
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Approved for type 2 diabetes as Cycloset, the exact mechanism by which it improves glycemic control remains unclear. More often used to treat hyperlipidemia, colesevelam (Welchol) is also indicated for type 2 diabetes. Being a nonabsorbed bile acid séquestrant, colesevelam can inhibit the absorption of other drugs, including fat-soluble vitamins.
CONCEPT REVIEW 34.1
* Why are noninsulin antidiabetic drugs ineffective for treating type 1 diabetes?
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Nursing Process Focus Patients Receiving Pharmacotherapy for Type 2 Diabetes
ASSESSMENT
POTENTIAL NURSING DIAGNOSES*
Same as for patients receiving insulin (see Core Concept 34.3), so abbreviated here. Prior to administration: * Obtain a complete health history.
* Evaluate laboratory blood findings.
* Acquire the results of a complete physical examination.
* Obtain a dietary history.
* Determine knowledge of diabetic medications and blood glucose monitoring.
Same as for patients receiving insulin (see Core Concept 34.3), so abbreviated here.
* Deficient Knowledge
* Ineffective Health Management
* Noncompliance
* Risk for Unstable Blood Glucose Level
* Risk for Injury
* Risk for Imbalanced Nutrition
* Risk for Infection
PLANNING: PATIENT GOALS AND EXPECTED OUTCOMES
The patient will:
* Experience therapeutic effects (stable blood glucose levels).
* Be free from or experience minimal adverse effects from drug therapy.
* Verbalize an understanding of the drug’s use, adverse effects, and required precautions.
* Demonstrate an understanding of lifestyle modifications necessary for successful maintenance of drug therapy.
IMPLEMENTATION
Interventions and (Rationales)
Patient Education/Discharge Planning
*Monitor blood glucose at least daily. (Daily glucose levels will assist in maintaining stable blood glucose.)
*Instruct the patient how to monitor blood glucose, including use of equipment, and when to notify the healthcare provider.
*Administer medication correctly (at appropriate time according to type of medication ordered), and evaluate the patient’s knowledge of proper administration. (Most oral antidiabetic medications are given at or around meal times. Maintaining levels of medication will assist in maintaining stable blood glucose levels.)
Inform patient or caregivers about:
* Correct administration time for type of medication ordered.
* Peak medication levels and proper food sources needed to prevent both hyperglycemia and hypoglycemia. Provide written materials for future reference.
*Monitor for signs of lactic acidosis if the patient is receiving a biguanide. (Mitochondrial oxidation of lactic acid is inhibited, and lactic acidosis may result.)
*Instruct the patient to report signs of lactic acidosis, such as hyperventilation, muscle pain, fatigue, and increased sleeping to the healthcare provider.
*Continue to monitor periodic laboratory work: CBC, electrolytes, glucose, HbA1C, lipid profile, liver and renal function studies. (Periodic monitoring assists in determining glucose control, need for medication changes, and any indicators of complications. These drugs are metabolized in the liver and may cause elevations in AST and LDH.)
Instruct the patient:
* On sulfonylureas to immediately report any nausea, vomiting, yellow skin, pale or clay colored stools, abdominal pain, or dark urine to the healthcare provider.
* Taking biguanides to immediately report any drowsiness, malaise, decreased respiratory rate, or general body aches to the healthcare provider.
* About the need to keep laboratory appointments.
Ensure dietary needs are met based on weight and current glucose levels. Avoid alcohol. (Patients taking sulfonylurea or biguanides should avoid alcohol entirely to prevent an antabuse-like reaction.)
Advise the patient to:
* Monitor food choices and follow recommended diet plan. Provide written materials on dietary recommendations for future reference.
* Abstain from alcohol and to avoid liquid over-the-counter (OTC) medications, which may contain alcohol.
(Continued)
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Nursing Process Focus (continued)
Interventions and (Rationales)
Patient Education/Discharge Planning
* Monitor for edema, blood pressure, and lung sounds in patients taking thiazolidiones. (These drugs may cause edema and worsening heart failure.)
* Instruct the patient to immediately report to the healthcare provider any signs of edema of the hands or feet, dyspnea, or excessive fatigue.
* Increase the frequency of blood glucose monitoring if the patient is experiencing fever, nausea, vomiting, or diarrhea. (Illness may affect blood glucose levels and usually requires adjustments in medication.)
* Instruct the patient to report the first signs of fatigue, muscle weakness, and nausea.
* Discuss the importance of adequate rest and healthy routines.
* Check for signs of hypoglycemia, especially around the time of insulin peak activity. If symptoms occur, provide a quick-acting carbohydrate source (juice or simple sugar), and then recheck blood glucose. (Using a simple sugar will raise blood sugar immediately.) Also monitor carefully patients who also take beta blockers, because early signs of hypoglycemia may not be apparent.
Inform the patient:
* Of the signs and symptoms of hypoglycemia, such as hunger, irritability, and sweating.
* At first sign of hypoglycemia, to check blood glucose and eat a simple sugar; if symptoms do not improve, call 911.
* If necessary, to monitor blood glucose before breakfast and supper.
* Not to skip meals and to follow a diet specified by the healthcare provider.
* Monitor weight, weighing at the same time of day each time. (Changes in weight will affect the amount of drug needed to control blood glucose.)
* Instruct the patient to weigh self each week, at the same time of day, and report any significant loss or gain.
* Encourage the patient to increase physical activity gradually but continue to monitor blood glucose level before and after exercise. (Exercise assists muscle cells to use glucose more efficiently, lowering blood glucose.)
Inform the patient:
* About the benefit of exercise.
* To check blood glucose before and after exercise and to keep a simple sugar on his or her person while exercising.
* To eat some form of simple sugar or complex carbohydrate before strenuous exercise as prophylaxis against hypoglycemia.
* Monitor hypersensitivity and allergic reactions. (Anaphylactic reactions are possible.)
* Advise the patient of the importance of immediately reporting symptoms such as skin rashes, itching, swelling of the tongue or face, flushing, dizziness, syncope, wheezing, throat tightness, or shortness of breath to the healthcare provider.
* Determine pregnancy status. (Some oral antidiabetic medications are category C and must be stopped during pregnancy. Due to increasing the metabolic needs of pregnancy, insulin therapy may be needed.)
* Advise female patients of childbearing age to inform the healthcare provider if pregnancy is suspected.
EVALUATION OF OUTCOME CRITERIA
Evaluate the effectiveness of drug therapy by confirming that patient goals and expected outcomes have been met (see “Planning”). See Table 34.2 fora list of drugs to which these nursing actions apply.
*Herdman, T.H. & Kamitsuru, S. (Eds.). Nursing Diagnoses: Definitions & Classification 2015-2017. Copyright © 2014, 1994-2014 NANDA International. Used by arrangement by John Wiley & Sons, Inc. Companion website: www.wiley.com/go/nursingdiagnoses.
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Patients Need to Know
Patients treated for DM need to know the following:
1. When administering insulin, meals should not be skipped. If self-injecting insulin, carefully follow all Instructions provided by the healthcare provider to avoid injury or Infection. Opened vials may be stored at room temperature for up to 1 month, avoiding direct sunlight and heat. Store unopened vials in refrigerator. Discard any vial if any changes in the solution are noted or if insulin has expired.
2. Check with a healthcare provider before beginning a vigorous exercise program. Often, insulin doses should be reduced or extra food should be ingested just prior to intense exercise.
3. Know the time of peak action of any Insulin, because that is when the risk for hypoglycemic adverse effects is greatest.
4. The right amount of insulin must be available to cells when glucose is available in the blood. Without Insulin present, glucose from a meal can build up to high levels in the blood, causing hyperglycemia and possible coma.
5. When taking antidiabetic drugs, report to your healthcare provider immediately any signs of hypoglycemia, such as weakness, sweating, dizziness, tremor, anxiety, or tachycardia. Mild symptoms may be treated with small amounts of sugar in the form of candy or fruit juice.
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6. Always take antidiabetic drugs the same time each day. When self-monitoring blood glucose, recall that normal values are 80-120 mg/dL before meals and 100-140 mg/dL before bedtime.
7. Read the directions for all medications very carefully because many drug-drug interactions are possible. Medications such as corticosteroids, thiazide diuretics, and sympathomimetics can raise blood glucose levels and inhibit the effects of insulin.
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Safety Alert: Use of Multidose Medication Pens
The FDA (2015) warns that multidose insulin pens, and pens for result in cross contamination causing the spread of disease. All other injectable medicines, never be shared among patients, medication pens should be clearly labeled with the patient’s even if the needle is changed. The practice of sharing pens can name or other identifying information.
Chapter Review Core Concepts Summary
34.1 The pancreas is responsible for the regulation of blood glucose levels.
The pancreas is both an endocrine and an exocrine gland. The islets of Langerhans are responsible for secretion of insulin and glucagon. Insulin is released when blood glucose increases, and glucagon is released when blood glucose decreases.
34.2 Type 1 diabetes is caused by a deficiency of insulin.
Type 1 DM is caused by an absolute lack of insulin secretion due to autoimmune destruction of pancreatic islet cells. If untreated, it results in serious, chronic conditions affecting the cardiovascular and nervous systems.
34.3 Insulin replacement therapy is required for type 1 diabetes.
Type 1 DM is treated by dietary restrictions, exercise, and insulin therapy. The many types of insulin preparations vary as to their onset of action, time to peak effect, and duration. Doses of insulin are highly individualized in each patient.
34.4 Type 2 diabetes is the most common form of the disorder
Type 2 DM is caused by a lack of sensitivity of insulin receptors at the target cells and a deficiency in insulin secretion. If untreated, the same chronic conditions result as in type 1 DM. Most people with type 2 DM are older adults; more obese children and adolescents are being diagnosed.
34.5 Antidiabetic drugs are prescribed after diet and exercise have failed to reduce blood glucose to normal levels.
Type 2 DM is controlled through lifestyle changes and oral hypoglycemic drugs. Various classes of drugs are available for the pharmacotherapy of type 2 DM: alpha-glucosidase inhibitors, biguanides, incretin mimetics, incretin enhancers, meglitinides, sodium-glucose co-transporter (SGLT) inhibitors, sulfonylureas, thiazolidinediones, and miscellaneous drugs. Combinations of antidiabetic drugs maximize therapeutic effects and minimize adverse effects.
REVIEW Questions
Answer the following questions to assess your knowledge of the chapter material, and go back and review any material that is not clear to you.
1. While collecting information from a patient, the nurse notes which of the following symptoms of type 1 diabetes? (Select all that apply.)
1. Poly
2. phagia
3. Polyuria
4. Polydipsia
5. Weight gain
6. Weight loss
2. When administering insulin, what route is used?
1. Oral
2. Intradermal
3. Subcutaneous
4. Intramuscular
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3. A patient who has just been prescribed an incretin enhancer (oral hypoglycemic medication) asks how it works. The nurse informs the patient that these types of medications:
1. Decrease the uptake of glucose by body cells.
2. Stimulate insulin release from the pancreas.
3. Increase insulin production by the pancreas.
4. Decrease the amount of insulin produced by the pancreas.
4. A patient receives NPH and regular insulin every morning. The nurse verifies that the patient understands that there are two different peak times to be aware of for this insulin combination. The reason why the nurse continues to evaluate the patient’s understanding in this instance is because:
1. The patient needs to plan the next insulin injection around the peak times.
2. Additional insulin may be needed at peak times to avoid hyperglycemia.
3. It is best to plan exercise or other activities around the peak insulin activity.
4. The risk for hypoglycemia is greatest around the peak of insulin activity.
5. The nurse is evaluating the patient’s knowledge about the use and effects of insulin. Which of the following statements indicates that the patient needs additional information?
1. “If 1 experience hypoglycemia, I should drink half a cup of apple juice.”
2. “My insulin needs may increase when I have an infection.”
3. “I must draw the NPH insulin first if I am mixing it with regular insulin.”
4. “If my blood glucose levels are above 140 mg/dL, I should notify my healthcare provider.”
6. The healthcare provider starts a patient on 500 mg, PO, twice a day. The pharmacy provides scored 1000 mg tablets. How many tablets will the patient take in 1 day?
1. One tablet
2. Two tablets
3. One and one-half tablets
4. One-half tablet
7. The patient with diabetes has decided to start an exercise program. He remembers that the nurse told him that exercise:
1. Increases glucose in the blood thus increasing the need for insulin just after exercise.
2. Decreases glucose in the blood thus decreasing the need for more insulin just after exercise.
3. Does not affect glucose or the need for insulin.
4. Decreases glucose in the blood thus increasing the need for insulin after exercise.
8. The nurse informs a group of patients, newly diagnosed with type 1 diabetes mellitus, that the following factors can influence the amount of insulin needed to control blood glucose levels: (Select all that apply.)
1. Exercise.
2. Diet.
3. Illness.
4. Sleep.
5. Weight.
9. The nurse administers glipizide (Glucotrol):
1. Subcutaneously only.
2. After meals.
3. At bedtime.
4. Just before breakfast.
10. The nurse plans to administer glargine (Lantus) to a patient with type 1 diabetes:
1. Before meals.
2. With meals.
3. Only at bedtime.
4. At the same time each day.
CASE STUDY Questions
Mr. Brian Jones.]
Remember Mr. Jones, the patient introduced at the beginning of the chapter? Now read the remainder of the case study. Based on the information you have learned in this chapter, answer the questions that follow.
Mr. Brian Jones is a 45-year-old firefighter who smokes and is somewhat overweight. Over the past 5 years, he has begun to develop slightly elevated blood pressure as determined by annual physical exams. He knows he should lose weight and is concerned about his energy level. He has always felt “okay” despite the fact that he smokes, but recently he has begun to feel sluggish and wonders what’s going on. He thinks to himself, “Maybe I’m just getting older.” At this current visit to the doctor, laboratory results reveal a fasting blood glucose level of 136 mg/dL. His blood pressure is 150/90 mmHg. Mr. Jones has not been taking medications for any reported disorders.
1. Mr. Jones is told that his blood glucose level is above the normal range, a condition known as hyperglycemia. In helping to determine factors that influenced his test results, the nurse asks him about: (Select all that apply.)
1. His daily diet.
2. His level of stress.
3. How long he has smoked.
4. How long he has had hypertension.
2. Mr. Jones is told that he has the symptoms of type 2 DM. He wants to know how it can be controlled. The nurse tells him that it can be controlled by: (Select all that apply.)
1. Regular exercise.
2. Oral antidiabetic medications.
3. Maintaining current weight.
4. Better coping skills to deal with stress.
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3. Mr. Jones is started on metformin and asks the nurse about adverse effects. The nurse states that some of the adverse effects of metformin are: (Select all that apply.)
1. Constipation.
2. Diarrhea.
3. Abdominal discomfort.
4. Headaches.
4. Mr. Jones also has high blood pressure and is going to be prescribed medication. The nurse understands that several blood pressure drugs –captopril, furosemide, and nifedipine –may cause a(n):
1. Increased risk for hypoglycemia.
2. Decreased renal excretion.
3. Increased renal excretion.
4. Decreased risk for hypoglycemia.
Answers and complete rationales for the Review and Case Study Questions appear in Appendix A
REFERENCES
Herdman, T. H., & Kamitsuru, S. (Eds.). (2014). NANDA International nursing diagnoses: Definitions and classification, 2015-2017. Oxford, United Kingdom: Wiley-Blackwell.
U. S. Food and Drug Administration. (2015). FDA drug safety communication: FDA requires label warnings to prohibit sharing of multi-dose diabetes pen devices among patients. Retrieved from http:/ /www.fda. gov / Drugs / DrugSafety / ucm435271 .htm
SELECTED BIBLIOGRAPHY
American Diabetes Association. (2016). Statistics about diabetes.
Retrieved at http://www.diabetes.org/diabetes-basics/statistics/?referrer=https://www.google.com American Diabetes Association. (2016). Standards of medical care in diabetes –2016. Retrieved from http://professional.diabetes.org/ResourcesForProfessionals.aspx?typ=17&cid=84160&pcid=8410
Anguita, M. (2013). Next generation of diabetes drugs arriving, but approach with caution. Nurse Prescribing, 11, 58-60. doi:10.12968/npre.2013.11.2.58
Bennett, W. L., Maruthur, N. M., Singh, S„ Segal, J. B., Wilson, L. M., Chatterjee, R., … Bolen, S. (2011). Comparative effectiveness and safety of medications for type 2 diabetes: An update including new drugs and 2-drug combinations. Annals of Internal Medicine, 154, 602-613. doi:10.7326/0003-4819-154-9-201105030-00336
Centers for Disease Control and Prevention. (2014). 2014 Diabetes national statistics report. Retrieved from http://www.cdc.gov/dia-betes/data/statistics/2014statisticsreport.html
Centers for Disease Control and Prevention. (2014). 2024 national diabetes statistics report: Estimates of diabetes and its burden in the United States. Retrieved at http://www.cdc.gov/diabetes/pdfs/ data/2014-report-estimates-of-diabetes-and-its-burden-in-the-united-states.pdf
Centers for Disease Control and Prevention, (n.d.). Women at high risk for diabetes: Physical activity, healthy eating, and weight loss. Retrieved at http://www.cdc.gov/diabetes/pubs/pdf/womenHighRiskDi-abetes.pdf
Maruthur, N. M., Tseng, E., Hutfless, S., Wilson, L. M., Suarez-Cuervo, C, Berger, Z., … Bolen, S. (2016). Diabetes medications as monotherapy or metformin-based combination therapy for type 2 diabetes: A systematic review and meta-analysis. Annals of Internal Medicine, 164, 740-751. doi:10.7326/M15-2650
Nathan, D. M. (2014). The diabetes control and complications trial/ epidemiology of diabetes interventions and complications study at 30 years: Overview. Diabetes Care, 37,9-16. doi:10.2337/dc13-2112
Powers, A. C, & D’Alessio, D. (2011). Endocrine pancreas and pharmacotherapy of diabetes mellitus and hypoglycemia. In L. L. Brunton, B. A. Chabner, & B. C Knollman (Eds.), Gordon and Gillman’s the pharmacological basis of therapeutics (12th ed., pp. 1237-1274). New York, NY: McGraw-Hill.
Rickels, M. R., Ruedy, K.J., Foster, N. C, Piché, C, Dulude, H., Sherr, J.,… Beck, R. (2016). Intranasal glucagon for treatment of insulin induced hypoglycemia in adults with type 1 diabetes: A randomized, cross-over non-inferiority study. Diabetes Care, 39, 264-270. doi:10.2337/dcl5-1498
Rotenstein, L. S., Kozak, B. M., Shivers, J. P., Yarchoan, M., Close, J., & Close, K. L. (2012). The ideal diabetes therapy: What will it look like? How close are we? Clinical Diabetes, 30, 44-53. doi:10.2337/ diaclin.30.2.44
Tseng, C. H., Lee, K. Y, Tseng, F. H. (2015). An updated review on cancer risk associated with incretin mimetics and enhancers. Journal of Environmental Science and Health Part C Environmental Carcinogenesis & Ecotoxicology Reviews, 33, 67-124. doi:10.1080/10590501.2 015.1003496
Wang, S. S. (2015). Metabolic syndrome. Retrieved from http://emedicine.medscape.com/article/165124-overview
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Chapter 35 Drugs for Disorders and Conditions of the Reproductive System
[Image: Ms. Marge Philips]
“I can’t wait until all this stops. My periods hurt so had and last so long. It just makes me tired.”
Ms. Marge Philips
Core Concepts Drug Snapshot
35.1 The hypothalamus, pituitary, and gonads control reproductive function in both men and women.
35.2 Oral contraceptives and extended-release formulations are drugs used in low doses to prevent pregnancy.
35.3 Hormone replacement therapy provides estrogen to treat postmenopausal symptoms, but benefits may not outweigh risks.
35.4 Conjugated estrogens and progestins are prescribed for dysfunctional uterine bleeding, endometrial cancer, and postmenopausal symptoms.
35.5 Oxytocics and tocolytics are drugs that influence uterine contractions and labor.
35.6 Androgens are used to treat hypogonadism in males.
35.7 Erectile dysfunction is a common disorder successfully treated with drug therapy.
35.8 In its early stages, benign prostatic hyperplasia is successfully treated.
Drug Snapshot
The following drugs are discussed in this chapter:
Drug Classes
Prototype Drugs I
Oral Contraceptives and extended-release formulations
estradiol with norethindrone (Ortho-Novum, others)
Hormone replacement therapy (HRT)
*** estrogen, conjugated (Cenestin, Enjuvia, Premarin)
Drugs for dysfunctional uterine bleeding
***medroxyprogesterone (Depo-Provera, Depo-SubQ-Provera, Provera)
Uterine stimulants and relaxants
***oxytocin (Pitocin)
Androgens
***testosterone
Drugs for erectile dysfunction
*** sildenafil (Viagra)
Drugs for benign prostatic hyperplasia
***finasteride (Proscar)
Learning Outcomes
After reading this chapter, the student should be able to:
1. Describe the roles of the hypothalamus, pituitary, and sex organs in maintaining female and male reproductive function.
2. Explain the mechanisms by which estrogens and progestins prevent conception.
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3. Describe the role of drug therapy in the treatment of menopausal and postmenopausal symptoms.
4. Discuss the uses of hormones in the therapy of dysfunctional uterine bleeding, endometrial cancer, and symptoms experienced after menopause in some women.
5. Compare and contrast the use of uterine stimulants and relaxants in the treatment of patients giving birth and after delivery of the baby.
6. Identify the reasons for pharmacotherapy with androgens.
7. Describe the pharmacotherapy of erectile dysfunction.
8. Describe the pharmacotherapy of benign prostatic hyperplasia.
Key Terms
amenorrhea (ah-men-oh-REE-ah)
androgens (AN-droh-jens)
benign prostatic hyperplasia (BPH) (bee- NINE pros-TAT-ik hy-PURR-plays-she-ah)
breakthrough bleeding corpora cavernosa (KORP-us kav-ver-NOH-sah)
corpus luteum (KORP-us LUTE-ee-uhm)
dysfunctional uterine bleeding
endometrial carcinoma (en-doh-MEE- tree-ahl CAR-sin-OH-mah)
endometriosis (en-doh-MEE-tree-oh-sis) estrogen (ES-troh-jen)
follicle-stimulating hormone (FSH)
gonadotropin-releasing hormone (GnRH)
(go-NAD-oh-TROPE-en)
hormone replacement therapy (HRT)
hypogonadism (hy-poh-GO-nad-izm)
impotence (IM-poh-tense) libido (lih-BEE-do)
luteinizing hormones (LH)
(LEW-ten-iz-ing) menopause (MEN-oh-paws)
menorrhagia (men-oh-RAGE-ee-uh)
oligomenorrhea(ol-ego-men-oh-REE-uh)
ovulation (ov-you-LAY-shun)
oxytocics (ox-ee-TOH-sicz)
oxytocin (ox-ee-TOH-sin)
postmenopausal bleeding
(POST-men-oh-pause-ahl)
premenstrual syndrome (PMS) (PREE-men-stroo-ahl)
progesterone (pro-JESS-ter-own)
prolactin (pro-LAK-tin)
prostaglandins (pros-tah-GLAN-dins)
testosterone (test-AHST-erh-own)
tocolytics (toh-koh-LIT-ikz)
virilization (veer-you-lih-ZAY-shun)
Hormones from the pituitary gland and the gonads provide for the growth and continued maintenance of the male and female reproductive systems. Reproductive hormones impact virtually every body system function, including coagulation, blood vessels, bone, muscles, overall body growth, and behavior. Hormonal therapy of the female reproductive system is used to achieve a variety of therapeutic goals, ranging from replacement therapy after menopause, to prevention of pregnancy, to milk production. The pharmacologic treatment of reproductive disorders in men is less complex because hormonal secretion in men is relatively constant throughout the adult lifespan. This chapter examines hormones and drugs used to treat disorders and conditions associated with the reproductive system.
*** Core Concept 35.1
The hypothalamus, pituitary, and gonads control reproductive function in both men and women.
Regulation of the reproductive system is achieved by hormones from the hypothalamus, pituitary gland, and sex organs. The hypothalamus secretes gonadotropin-releasing hormone (GnRH), which travels a short distance to the pituitary to stimulate the secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Both of these pituitary hormones, when released, target the reproductive organs. The hormonal changes that occur during the ovarian and uterine cycles are illustrated in Figure 35.1.
During a woman’s reproductive years and under the influence of FSH and LH, several ovarian follicles begin the maturation process each month. On approximately day 14 of the ovarian cycle, a surge of LH secretion causes one follicle to expel its oocyte, a process called ovulation. The ruptured follicle, minus its oocyte, remains in the ovary and is transformed into the hormone-secreting corpus luteum. The expelled oocyte begins its journey through the uterine tube and eventually reaches the uterus. If conception does not occur, the outer lining of the uterus degenerates and is shed to the outside during menstruation.
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gonads/gonado = sex organs
tropin = attraction toward
luteum/luteinizing = yellowing (color of developing structures)
corpus = body
oocyte = egg cell
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estro = desire
gen = forming
pro = before
gest = gestation
testo = testis
erone/sterone = sterol chemical compound
FIGURE 35.1 Hormonal changes during the ovarian and uterine cycles.
As ovarian follicles mature, they secrete the female sex hormones estrogen and progesterone. Estrogen is responsible for the maturation of the female reproductive organs and for the appearance of secondary sex characteristics. In addition, estrogen has numerous metabolic effects on nonreproductive tissues in the body. When women enter menopause at about age 50 to 55, the ovaries stop secreting estrogen.
In the last half of the monthly cycle, the corpus luteum secretes progesterone. In combination with estrogen, progesterone promotes breast development and regulates the monthly changes in the uterus. Under the influence of estrogen and progesterone, the uterine lining thickens in preparation for receiving a fertilized egg. High progesterone and estrogen levels in the final part of the uterine cycle provide negative feedback to shut off GnRH, FSH, and LH secretion. This negative feedback loop is illustrated in Figure 35.2.
The same pituitary hormones that control reproductive function in women also affect men. FSH regulates sperm production. LH regulates the production of testosterone. If the level of testosterone in the blood rises above normal, negative feedback to the pituitary shuts off the secretion of LH and FSH.
Testosterone is the primary male sex hormone responsible for male secondary sex characteristics. Unlike the 28-day cyclic secretion of estrogen and progesterone in women, testosterone secretion is relatively constant. Beginning in puberty, testosterone production increases rapidly and is maintained at a high level until late adulthood, after which it slowly declines.
CONTRACEPTIVES Core Concept 35.2***
Oral contraceptives and extended-release formulations are drugs used in low doses to prevent pregnancy.
The most widespread pharmacologic use of the female sex hormones is for the prevention of pregnancy. When used appropriately, they are nearly 100% effective. When contraceptives are taken orally, they are referred to as oral contraceptives (OCs). Many OCs contain a combination of estrogen and progestin, although a few contain only progestin.
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FIGURE 35.2 Hormonal control over male and female reproductive hormones.
The most common estrogen used in these preparations is ethinyl estradiol, and the most common progestin is norethindrone.
The estrogen-progestin OCs prevent ovulation, which is required for conception to occur. These hormones act by providing negative feedback to the pituitary gland that shuts down secretion of LH and FSH. Without these pituitary hormones, the egg cannot mature, and ovulation is prevented. The estrogen-progestin agents also make the lining of the uterus less favorable to receiving an embryo.
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mono = single
bi = two
tri = three
quadra = four
phasic = closing level(s)
dys = abnormal or unhealthy
meno = monthly
rrhea = flow
thrombo = stationary blood clot
embolytic = circulating blood clot
There are four types of estrogen-progestin OCs: monophasic, biphasic, triphasic, and quadriphasic version. The monophasic delivers a constant dose of estrogen and progestin throughout the 21-day treatment cycle. With biphasic formulations, the amount of estrogen in each pill remains constant, but the amount of progestin is increased toward the end of the treatment cycle to better nourish the uterine lining. In triphasic formulations, the amounts of both estrogen and progestin vary in three distinct phases during the treatment cycle. Natazia, a quadraphasic contraceptive, contains a synthetic estrogen called estradiol valerate and a progestin called dienogest; it is the first drug containing this specific combination. Natazia has not been tested in women with obesity, and since OCs are less effective in obesity, this medication may well not be effectual in this instance. Due to increased risks of heart disease, healthcare providers are discouraged from prescribing oral OCs to patients with a high BMI. All four types of OC formulations are equally efficacious, although a common problem, and most likely the most common reason for treatment failure (pregnancy), is forgetting to take the medication daily. Selected OCs are listed in Table 35.1.
The most common adverse effects of estrogen-progestin OCs are nausea, breast tenderness, weight gain, and breakthrough bleeding. Less common serious effects include edema, gallbladder disease, abdominal cramps, changes in urinary function, dysmenorrhea, fatigue, skin rash, headache, and vaginal candidiasis. Cardiovascular adverse effects, the most serious of all, include hypertension and thromboembolic disorders. The estrogen component of the pill can lead to venous and arterial thrombosis, which can result in pulmonary, myocardial, and thrombotic strokes.
The progestin-only OCs, sometimes called minipills, prevent pregnancy primarily by producing a thick, viscous mucus at the entrance to the uterus that prevents penetration by sperm. A thicker mucosal lining inhibits implantation of a fertilized egg. Progestin-only agents are less effective than estrogen-progestin combinations and produce a higher incidence of menstrual irregularities. Because of this, they are generally reserved for women who are at high risk for adverse effects from estrogen. Unlike estrogens, progestins are not associated with a higher risk of thromboembolic events, and they have no effect on breast cancer.
Table 35.1 Selected Oral Contraceptives
Trade Name
Estrogen
Progestin
MONOPHASIC
Desogen
ethinyl estradiol: 30 meg
desogestrel: 0.15 mg
Loestrin 1.5/30 Fe
ethinyl estradiol: 30 meg
norethindrone: 1.5 mg
Ortho-Cyclen-28
ethinyl estradiol: 35 meg
norgestimate: 0.25 mg
Yasmin
ethinyl estradiol: 30 meg
drospirenone: 3 mg
Zovia 1/50E-21 and 28
ethinyl estradiol: 50 meg
ethynodiol diacetate: 1 mg
BIPHASIC
Mircette
ethinyl estradiol: 20 meg for 21 days; 10 meg for 5 days
desogestrel: 0.15 mg for 21 days
TRIPHASIC
*** Ortho-Novum 7/7/7-28
ethinyl estradiol: 35 meg
norethindrone: 0.50, 0.75, 0.1 mg
Ortho Tri-Cyclen-28
ethinyl estradiol: 35 meg
norgestimate: 0.18, 0.215, 0.25 mg
Trivora-28
ethinyl estradiol: 30, 40, 30 meg
levonorgestrel: 0.05, 0.075, 0.125 mg
QUADRAPHASIC
Natazia
ethinyl valerate: 3, 2, 2, 1 mg
dienogest: 0, 2, 2, 0 mg
PROGESTIN ONLY
Micronor
None
norethindrone: 0.35 mg
Nor-Q.D.
None
norethindrone: 0.35 mg
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Some contraceptives are available as topical, intradermal, or injectable formulations. Several long-term hormonal formulations are available. These extended-duration contraceptives are equally effective in preventing pregnancy and have the same basic safety profile as OCs. Examples of alternative formulations are:
* Depot injections: Depo-Provera (IM injection of medroxyprogesterone) and Depo-SubQ-Provera (subcutaneous injection of medroxyprogesterone) provide up to 3 months of contraception.
* Implants: Implanon is a single rod containing the progestin etonogestrel that is inserted under the skin of the upper arm and provides up to 3 years of contraception.
* Transdermal patches: Ortho Evra is a transdermal patch containing ethinyl estradiol and norelgestromin that provides 7 days of contraception.
* Vaginal route: NuvaRing is a 2-inch-diameter ring containing estrogen and progestin that is inserted into the vagina to provide 3 weeks of contraceptive protection.
* Intrauterine route: Mirena is a polyethylene cylinder placed in the uterus that releases levonorgestrel to provide 5 years of contraception. Skyla is smaller than Mirena and may last up to 3 years.
* Extended regimen OCs: Seasonale in tablet form containing levonorgestrel and ethinyl estradiol is taken for 84 consecutive days, followed by 7 inert tablets (without hormones).
Emergency contraception (EC) is the prevention of pregnancy following unprotected intercourse. The treatment goal for EC is to provide effective and immediate contraception. Two different medications are approved for EC: Levonorgestrel (Plan B) and ulipristal (Ella).
Plan B is approved for purchase over the counter (OTC). Dosing for Plan B involves taking 0.75 mg of levonorgestrel in two doses, 12 hours apart. Plan B One Step includes a single 1.5 mg dose. The drug acts in a manner similar to OCs; it prevents ovulation and also alters the lining of the uterus so that implantation does not occur. If implantation has already occurred, Plan B will not terminate the pregnancy. Plan B must be taken as soon as possible after unprotected intercourse; if taken more than 120 hours later, it becomes less effective. Adverse effects are mild and may include nausea, vomiting, abdominal pain, fatigue, headache, menstrual changes, diarrhea, dizziness, and breast tenderness. Ulipristal (Ella) is a single-dose product for EC that requires a prescription. One advantage of ulipristal is that it retains its effectiveness for 5 days following unprotected sex.
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Prototype Drug: *** Estradiol with Norethindrone (Ortho-Novum, Others)
Therapeutic Class: Oral Contraceptive Pharmacologic Class: Estrogen/Progestin
Actions and Uses: Ortho-Novum is typical of the monophasic OCs, containing fixed amounts of estrogen and progesterone for 21 days followed by placebo tablets for 7 days. It is nearly 100% effective at preventing conception. If a dose is missed, the patient should take the dose as soon as possible, or take two tablets the next day. If two consecutive doses are missed, conception is possible, and the patient should use other birth control methods until the regular dosing schedule is reestablished.
Adverse Effects and Interactions: Like most OCs, Ortho-Novum can increase the risks of thromboembolic disease: the potential for blood clots, hemorrhage, pulmonary embolism, or stroke. It should be used with caution in women with hypertension because it has the potential to raise blood pressure. Bleeding in the early or mid-menstrual cycle is relatively common.
Ethinyl estradiol interacts with many drugs. For example, rifampin, some antibiotics, barbiturates, anticonvulsants, and antifungals decrease efficacy of oral contraceptives, so the risks of breakthrough bleeding and pregnancy are higher
BLACK BOX WARNING:
Cigarette smoking increases the risk of serious cardiovascular adverse effects in women who are taking OCs containing estrogen. This risk increases dramatically in women over the age of 35. The absolute risks associated with OC use and smoking are greater because of the steeply rising incidence of arterial diseases. The combination of smoking and OC use among such women is associated with increased risk of stroke, acute myocardial Infarction, and venous thromboembolism.
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Nursing Process Focus Patients Receiving Contraceptive Therapy
ASSESSMENT
POTENTIAL NURSING DIAGNOSES*
Prior to administration:
* Obtain a complete health history, Including genitourinary, sexual, cardiovascular (especially hypertension or thromboembolic), thyroid, renal and liver conditions; pregnancy (or lactating); allergies; drug history; and possible drug interactions.
* Gather information about lifestyle, such as cigarette smoking and diet.
* Evaluate laboratory blood findings: complete blood count (CBC), electrolytes, lipid panel, renal, coagulation, and liver function studies.
* Acquire the results of a complete physical examination, including vital signs, height, weight, and menstrual pain
* Deficient Knowledge related to a lack of Information about drug therapy
* Infective Health Maintenance related to noncompliance with medication regimen or adverse drug effects
* Excess Fluid Volume related to adverse drug effects
* Risk for Ineffective Peripheral Tissue Perfusion related to adverse drug effects
PLANNING: PATIENT GOALS AND EXPECTED OUTCOMES
The patient will:
* Experience therapeutic effects (effective birth control).
* Be free from or experience minimal adverse effects from drug therapy.
* Verbalize an understanding of the drug’s use, adverse effects, and required precautions.
IMPLEMENTATION
Interventions and (Rationales)
Patient Education/Discharge Planning
*Administer medication correctly and evaluate the patient’s knowledge of proper administration. (Incorrect use may lead to pregnancy.)
Instruct the patient to:
* Take the pill at the same time every day.
* Not omit, increase, or decrease doses without consulting a healthcare provider. Omitting or decreasing doses increases the chance of pregnancy.
* For estrogen-progestin combinations: Take a missed dose as soon as remembered. If two consecutive doses are missed, take the two missed pills on the day remembered and the next two pills on the following day. Then follow the remaining schedule of pills but use additional birth control until the regular schedule is reestablished.
* Contact the healthcare provider if two consecutive periods are missed because pregnancy may have occurred.
*Monitor for the occurrence of breakthrough bleeding. (Spotting may occur, especially with low-dose hormone therapy, at mid-cycle. Any continuous, unusual, or heavy bleeding may indicate adverse effects, pregnancy loss, or disease and should be reported.)
Inform the patient that spotting may occur with low-dose hormone therapy at mid-cycle but to report any unusual changes In the amount of bleeding or if bleeding continues.
*Monitor for thrombophlebitis or other thromboembolic disease. (Estrogen predisposes to thromboembolic disorders by increasing levels of clotting factors.)
*Instruct the patient to immediately report to the healthcare provider any pain in the calves, limited movement in the legs, dyspnea, sudden severe chest pain, headache, seizures, anxiety, or fear.
*Monitor for cardiac disorders: Take vital signs, especially pulse and blood pressure. (These drugs can increase blood levels of angiotensin and aldosterone, which increase blood pressure.)
Instruct the patient to:
* Report immediately signs of possible cardiac problems such as chest pain, dyspnea, edema, tachycardia or bradycardia, and palpitations.
* Monitor blood pressure regularly.
* Report any symptoms of hypertension such as headache, flushing, fatigue, dizziness, palpitations, tachycardia, and nosebleeds.
Encourage the patient not to smoke. (Smoking increases the risk of thromboembolic disease.)
Instruct the patient to be aware that:
* The combination of OCs and smoking greatly increases the risk of cardiovascular disease, especially myocardial infarction (Ml).
* The risk increases with age (> 35) and with the number of cigarettes smoked (15 or more per day).
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Interventions and (Rationales)
Patient Education/Discharge Planning
* Monitor liver function tests, lipid profile studies, and thyroid studies periodically. (These drugs are associated with an increased risk of gallbladder disease and a rare risk of liver toxicity.)
Instruct the patient to:
* Return periodically for laboratory tests.
* Report any symptoms of abdominal or right upper quadrant discomfort, yellowing of the skin or sclera, fatigue, anorexia, darkened urine, or clay-colored stools to the healthcare provider.
* Monitor for the development of breast or other estrogen-dependent tumors. (Estrogen may cause tumor growth or proliferation.)
* Instruct the patient to immediately report to the healthcare provider if a first-degree relative is diagnosed with any estrogen-dependent tumor.
* Encourage compliance with follow-up treatment. (Follow-up is necessary to avoid serious adverse effects.)
Instruct the patient to:
* Schedule annual Pap smears.
* Perform breast self-exams (BSEs) monthly, and obtain routine mammograms as recommended by the healthcare provider.
EVALUATION OF OUTCOME CRITERIA
Evaluate the effectiveness of drug therapy by confirming that patient goals and expected outcomes have been met (see “Planning”). See Table 35.1 fora list of drugs to which these nursing actions apply.
*Herdman, T.H. & Kamitsuru. S. (Eds.), Nursing Diagnoses: Definitions & Classification 2015-2017. Copyright © 2014, 1994-2014 NANDA International. Used by arrangement by John Wiley & Sons, Inc. Companion website: www.wiley.com/go/nursingdiagnoses.
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CAM Therapy | Dong Quai for Premenstrual Syndrome
Since antiquity, dong quai has been recognized as an important herb for women’s health In Chinese medicine. Obtained from Angelica sinensis, a small plant that grows In China, dong quai contains a number of active substances that are said to exert analgesic, antipyretic, anti-inflammatory, and antispasmodic activity. The dried root is available as capsules, tablets, teas, and tinctures.
The reproductive effects of dong quai may be due to active substances that have estrogenic activity. These estrogenic Ingredients act as a “uterine tonic” to improve the overall hormonal balance of the female reproductive system. Dong quai is used to treat the symptoms of premenstrual syndrome, as well as Irregular menstrual periods and painful menstruation.
Dong quai has also been used for its cardiovascular effects. It is claimed to increase circulation by dilating blood vessels. Because some of the active Ingredients of dong quai may have anticoagulant activity, patients taking warfarin (Coumadin) or high doses of aspirin should not take the herb without notifying their healthcare provider.
MENOPAUSE *** Core Concept 35.3
Hormone replacement therapy provides estrogen to treat postmenopausal symptoms, but benefits may not outweigh risks.
Menopause is the permanent cessation of menstruation, resulting in a lack of estrogen secretion by the ovaries. Menopause is neither a disease nor a disorder, but a natural consequence of aging that is often accompanied by unpleasant symptoms that include hot flashes, night sweats, irregular menstrual cycles, vaginal dryness, and bone mass loss.
Over the past 50 years, healthcare providers have commonly prescribed hormone replacement therapy (HRT) for menopause. HRT supplies physiological doses of estrogen, sometimes combined with a progestin, to treat unpleasant symptoms of menopause and to prevent the long-term consequences of estrogen loss.
Studies have raised questions regarding the safety of HRT for menopause. Data suggest that patients may have an increased risk of coronary artery disease, stroke, and venous thromboembolism. Combination HRT increases breast cancer risk even when used for only a short time. Estrogen-only HRT increases the risk of ovarian cancer and also breast cancer, especially when used for a number of years. Women are encouraged to discuss alternatives with their healthcare provider. Undoubtedly, research will continue to provide valuable information on the long-term effects of HRT. Until then, the choice of HRT to treat menopausal symptoms will remain a highly individualized one between the patient and her healthcare provider.
[sidebar]
post = after
meno = monthly
pause/pausal = stopping
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hyster = womb or uterus
ectomy = excision
endo = inside (e.g., uterus lining)
metri/metrial = measure
osis = abnormal
oligo = scanty
meno = month
rrhagia = excessive
rrhea = flow
osteo = bone
porosis = porous condition
UTERINE ABNORMALITIES
Conjugated estrogens and progestins are prescribed for dysfunctional uterine bleeding, endometrial cancer, and postmenopausal symptoms.
Conjugated estrogens are combined estrogens, and these, along with progestins, treat a variety of conditions. Dysfunctional uterine bleeding is a condition in which hemorrhage occurs on a noncyclic basis or in abnormal amounts. It is the most frequent health problem reported by women and is a common reason for hysterectomy. Other types of uterine abnormalities include the following:
* Amenorrhea –absence of menstruation
* Endometriosis –abnormal location of endometrial tissues
* Oligomenorrhea –infrequent menstruation
* Menorrhagia –prolonged or excessive menstruation
* Breakthrough bleeding –hemorrhage between menstrual periods
* Premenstrual syndrome (PMS) –symptoms develop during the luteal phase
* Postmenopausal bleeding –hemorrhage following menopause
* Endometrial carcinoma –cancer of the endometrium
Dysfunctional uterine bleeding is often caused by a hormonal imbalance between estrogen and progesterone. Rather than rising and falling on a normal 28-day cycle, estrogen levels remain constant, resulting in chronic stimulation of the uterine lining. Without the presence of adequate amounts of progestins (progesterone-like hormones) to limit and stabilize growth of the uterine lining, irregular and prolonged bleeding occurs.
The primary indication for conjugated estrogens has been to treat moderate to severe symptoms of menopause, which include irregular menstrual cycles and extreme uterine bleeding. Progestins are the drugs most commonly used for treating uterine abnormalities. Administration of a progestin in a pattern starting 5 days after the onset of menses and continuing for the next 20 days can sometimes reestablish a normal, monthly cyclic pattern. OCs may also be prescribed for this disorder. Progestins are also occasionally prescribed for the treatment of metastatic endometrial carcinoma. In cases like this, progestins are used for total patient care, usually in combination with other antineoplastics. Conjugated estrogens and selected progestins with their dosages are listed in Table 35.2.
CONCEPT REVIEW 35.1
Why is a progestin usually prescribed along with estrogen in oral contraceptives and when treating postmenopausal symptoms?
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Prototype Drug:***Estrogen, conjugated (Cenestin, Enjuvia, Premarin)
Therapeutic Class: Hormone replacement therapy Pharmacologic Class: Estrogen
Actions and Uses: Conjugated estrogens (Premarin) contain a mixture of different natural estrogens. Conjugated estrogen A (Cenestin) and conjugated estrogen B (Enjuvia) contain a mixture of 9-10 different synthetic plant estrogens. Conjugated estrogens exert several positive metabolic effects, including an increase in bone density and a reduction in LDL cholesterol. It may also lower the risk of coronary artery disease and colon cancer in some patients.
Adverse Effects and Interactions: Adverse effects of conjugated estrogens include nausea, fluid retention, edema, breast tenderness, abdominal cramps, and bloating. Conjugated estrogens are contraindicated in pregnant patients and in women with breast cancer. Caution should be used when treating patients with a history of thromboembolic disease, hepatic impairment, or abnormal uterine bleeding.
Drug interactions include a decreased effect of tamoxifen and anticoagulants. The effects of estrogen may be decreased if taken with barbiturates, and there is a possible increased effect of tricyclic antidepressants.
BLACK BOX WARNING:
Estrogens, when used alone, have been associated with a higher risk of endometrial cancer in postmenopausal women. Although adding a progestin may exert a protective effect by lowering the risk of uterine cancer, studies suggest that progestin may increase the risk of breast cancer following long-term use.
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Table 35.2 Drugs for Hormone Replacement Therapy and Uterine Abnormalities
Drug
Route and Adult Dose
Remarks
ESTROGENS
estradiol (Mora, Climara, Divigel, Elestrin, Estraderm, Estrace, others)
PO (Estrace): 0.5-2 mg daily
Transdermal patch: 1 patch once weekly (Climara) or twice weekly (Alora, Estraderm)
Topical gel (Divigel, Elestrin): 0.25-1 g/day applied to the upper thigh or arm
Intravaginal cream (Estrace): Insert 1-4 g/day
Systemic estrogens come in pill form, skin patches, gels, creams, and sprays. Low-dose vaginal preparations of estrogen are available in cream, tablet, and ring form. Estradiol valerate IM injection is a long-acting estrogen dissolved in sterile oil solution.
***estradiol valerate (Delestrogen)
IM: 10-20 mg every 4 weeks
estrogen, conjugated (Cenestin, Enjuvia, Premarin)
PO: 0.3-1.25 mg/day for 21 days each month
estropipate (Ogen)
PO: 0.75-6 mg/day for 21 days each month Intravaginal cream (Ogen): Insert 2-4 g/day
PROGESTINS
*** medroxyprogesterone (Depo-Provera, Depo-SubQ-Provera, Provera)
PO: 5-10 mg daily on days 1-12 of the menstrual cycle IM (Depo-Provera): 150 mg daily for 3 months. Give the first dose during the first 5 days of the menstrual period Subcutaneous (Depo-SubQ-Provera): 104 mg daily for 3 months. Give the first dose during the first 5 days of the menstrual period
Synthetic versions of progestin are generally provided as high-dose pills or birth control pills. Injectable forms are also available. Treatments help restore hormonal balance.
norethindrone (Micronor, Norlutin, Nor-Q.D.)
PO (for amenorrhea): 5-20 mg/day on days 5-25 of the menstrual cycle
progesterone (Crinone, Endometrin, Prochieve, Prometrium)
Amenorrhea or functional uterine bleeding: IM: 5-10 mg/day Assisted reproductive technology: Intravaginal: 90 mg gel once daily or 100 mg tablets bid-tid
ESTROGEN-PROGESTIN COMBINATIONS
Conjugated estrogens with medroxyprogesterone (Premphase, Prempro)
PO: Premphase: Estrogen 0.625 mg/daily on days 1-28; add 5 mg medroxyprogesterone daily on days 15-28 PO: Prempro: Estrogen 0.3 mg and medroxyprogesterone 1.5 mg daily
Intravaginal cream: Insert 1/2 to 2 g daily for 3-6 months
Conjugated estrogens combined with progestins are prescribed to help women treat symptoms of menopause. Preparations are also used to treat certain menstrual disorders and to prevent osteoporosis (bone loss) in women.
estradiol with norgestimate (Pretest)
PO: 1 mg estradiol for 3 days, followed by 1 mg estradiol combined with 0.09 mg norgestimate for 3 days.
ethinyl estradiol with norethindrone acetate (Activella)
PO: 1 tablet daily, which contains 0.5-0.1 mg of estradiol and 0.5-1 mg norethindrone Transdermal patch; 1 patch, twice weekly
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Prototype Drug: *** Medroxyprogesterone (Depo-Provera, Depo-SubQ-Provera, Provera)
Therapeutic Class: Drug for endometriosis and dysfunctional uterine bleeding and endometriosis Pharmacologic Class: Progestin
Actions and Uses: Medroxyprogesterone is a synthetic progestin with a prolonged duration of action. As with its natural counterpart, the primary target tissue for medroxyprogesterone is the endometrium of the uterus. It inhibits the effect of estrogen on the uterus, thus restoring normal hormonal balance. Indications include dysfunctional uterine bleeding, secondary amenorrhea, and contraception.
Medroxyprogesterone may also be given by sustained release IM (Depo-Provera) or subcutaneous (Depo-SubQ-Provera) depot injection. This is available in two doses: a lower dose for contraception and a higher dose for the alleviation of inoperable metastatic uterine or renal carcinoma.
Adverse Effects and Interactions: The most frequent adverse effects of medroxyprogesterone are breast tenderness, breakthrough bleeding, and other menstrual irregularities. Weight gain, depression, hypertension, nausea, vomiting, dysmenorrhea, and vaginal candidiasis may also occur. The most serious adverse effect is an increased risk for thromboembolic disease.
Medroxyprogesterone is contraindicated during pregnancy and in women with known or suspected carcinoma of the breast. Caution should be used when treating patients with a history of thromboembolic disease, hepatic impairment, or undiagnosed vaginal bleeding.
BLACK BOX WARNING:
Progestins combined with conjugated estrogens may increase the risk of stroke, deep venous thrombosis (DVT), Ml, pulmonary emboli, and invasive breast cancer.
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oxytocic = oxytocin-related
toco = contraction
lytic = arrested
post = after
partum = childbirth
preterm = before term
LABOR AND BREASTFEEDING Core Concept 35.5***
Oxytocics and tocolytics are drugs that influence uterine contractions and labor.
Several drugs are used to manage uterine contractions and to stimulate lactation. Oxytocics are drugs that stimulate uterine contractions to promote the induction of labor. Tocolytics are used to inhibit uterine contractions during premature labor. These drugs are listed in Table 35.3.
The most widely used oxytocic is the natural hormone oxytocin, which is secreted by the posterior portion of the pituitary gland. The target organs for oxytocin are the uterus and the breast. As the growing fetus distends the uterus, oxytocin is secreted in increasingly larger amounts, thus promoting labor and the delivery of the baby. This process is referred to as positive feedback.
In postpartum women, oxytocin is released in response to suckling, which causes milk to be ejected (let down) from the mammary glands. Oxytocin does not increase the volume of milk production. This function is provided by the pituitary hormone prolactin, which increases the synthesis of milk.
Several prostaglandins, including dinoprostone (Cervidil, Prepidil) and carboprost (Hemabate), are also used as uterine stimulants. Unlike most hormones, which travel through the blood to affect distant tissues, prostaglandins are local hormones that act directly at the site where they are secreted. These drugs are used to initiate labor, dilate the cervix prior to delivery, and control hemorrhage following delivery.
Tocolytics are given as uterine relaxants to suppress preterm labor. This option is carefully weighed against harm to the mother and the baby. Risks to the baby involve an elevated heart rate, circulatory collapse, and respiratory paralysis. Risk to the mother is elevated blood pressure. Of the tocolytics listed in Table 35.3, only hydroxyprogesterone (Makena) is approved for this indication; the others are used off-label.
Table 35.3 Uterine Stimulants and Relaxants
Drug
Route and Adult Dose
Remarks
OXYTOCIC
oxytocin (Pitocin)
IV: To control postpartum bleeding: 10-40 units per Infusion pump in 1000 mL of IV fluid
IV: To induce labor: 0.5-2 milliunits/min, gradually increasing the dose at 30-60 minute intervals until contraction pattern is established
Rapidly causes uterine contractions and induces labor; postpartum bleeding is controlled due to its stimulatory effect on uterine smooth muscle
ERGOT ALKALOID
methylergonovine (Methergine)
PO: 0.2-0.4 mg bid-qid
Ergot alkaloids help to prevent and control bleeding after delivery of the baby
PROSTAGLANDINS
carboprost (Hemabate)
IM: 250 meg repeated at 1/1/2- and 3/1/2-hour intervals if indicated by uterine response
Prostaglandins make uterine muscles contract; during the uterine cycle, they naturally help the uterus shed its lining; clinically, these drugs are for refractory postpartum uterine bleeding
dinoprostone (Cervidil, Prepidil)
Intravaginal: 10 mg
TOCOLYTICS
magnesium sulfate
IV: 1-4 g in 5% dextrose by slow infusion (Initial max dose = 10-14 g/day, then no more than 30-40 g/day at a max rate of 1-2 g/hour)
These drugs inhibit uterine contractions in pregnant women at risk for preterm labor. Drugs are from different classes: magnesium sulfate (mineral supplement), hydroxyprogesterone (progestin), nifedipine (calcium channel blocker), and terbutaline (beta-adrenergic drug)
hydroxyprogesterone (Makena)
IM: 250 mg once weekly, beginning at 16 week gestation and continuing until week 37
nifedipine (Adalat, Procardia)
PO: Initial dosage of 20 mg, followed by 20 mg after 30 minutes (max: 160 mg/day)
After 72 hours, if still required, long-acting nifedipine 30-60 mg daily can be used
terbutaline (Brethine)
IV: 2.5-10 mcg/min (max: 17.5-30 mcg/min)
PO: Maintenance dose: 2.5-10 mg every 4-6 hours
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* What is the difference between the effects of prolactin and oxytocin on the breast?
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Prototype Drug: *** Oxytocin (Pitocin)
Therapeutic Class: Drug to induce labor; uterine stimulant Pharmacologic Class: Oxytocic
Actions and Uses: Oxytocin (Pitocin), identical to the natural hormone secreted by the posterior pituitary gland, is a preferred drug for inducing labor. It is timed to the final stage of pregnancy, after the cervix has dilated, membranes have ruptured, and presentation of the fetus has occurred. Oxytocin may also be administered to reduce postpartum hemorrhage after expulsion of the placenta.
Adverse Effects and Interactions: The most common adverse effects of oxytocin are elevated blood pressure; rapid, painful uterine contractions; and fetal tachycardia. Serious
complications in the mother may include uterine rupture, seizures, or coma. Risk of uterine rupture increases in women who have delivered five or more children.
BLACK BOX WARNING:
Oxytocin is not indicated for the elective induction of labor (the Initiation of labor in a pregnant patient who has no medical reason for induction).
HYPOGONADISM *** Core Concept 35.6 Androgens are used to treat hypogonadism in males.
Androgens are male sex hormones. Testosterone is the primary androgen. Lack of sufficient testosterone secretion by the testes can result in male hypogonadism, the reduced function of gonads or sex organs in the body. Hypogonadism may be congenital or acquired later in life. When the condition is caused by a testicular disorder, it is called primary hypogonadism. Without sufficient FSH and LH secretion by the pituitary, the testes will lack their stimulus to produce testosterone. This condition is known as secondary hypogonadism. Lack of FSH and LH secretion may have a number of causes, including Cushing syndrome (negative feedback from corticosteroids), thyroid disorders, and estrogen-secreting tumors.
Symptoms of male hypogonadism include a diminished appearance of the secondary sex characteristics of men: sparse axillary (armpit) hair, less facial and pubic hair; increased subcutaneous fat; and small testicular size. In adult men, lack of testosterone can lead to erectile dysfunction, low sperm counts, and decreased libido or interest in sex. In young men, lack of sufficient testosterone secretion may lead to delayed puberty.
Pharmacotherapy of hypogonadism includes replacement therapy with testosterone or other androgens. Within days or weeks of initiating therapy, androgens improve libido and correct erectile dysfunction resulting from low testosterone levels. Male sex characteristics reappear, a condition called masculinization or virilization. Therapy with androgens is targeted to return serum testosterone to normal levels. Above-normal levels serve no therapeutic purpose and increase the risk of adverse effects. High levels of androgens may cause abnormal growth of body hair, testicular shrinkage, altered sex drive, development of breasts, infertility, severe acne on the face and back, and possible mood swings involving rage or depression.
Testosterone is available in a variety of formulations to better meet individual patient preferences and lifestyles:
* Implantable pellets (subcutaneous): Testopel includes one to six pellets implanted on the anterior abdominal wall.
* Intramuscular (IM): Testosterone cypionate (Depo-Testosterone), testosterone undecanoate (Aveed), and testosterone enanthate (Delatestryl).
* Testosterone buccal system: Striant tablet is applied to the gum area just above the front teeth, producing a continuous supply of testosterone in the bloodstream.
* Transdermal testosterone gel: Androgel, Fortesta, Vogelexo, and Testim are applied once daily to the upper arms, shoulders, or abdomen. The drug is absorbed across the skin and into the bloodstream.
* Transdermal testosterone patch: Androgen patch is applied directly to the upper arm, thigh, back, or abdomen.
* Testosterone intranasal gel: Natesto is applied one spray in each nostril, three times daily.
Selected androgens with indications for men are listed in Table 35.4.
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andro = male
gen = forming
hypo = reduced
gonadism = sex hormone function
libido = sexual desire
virilization = appearance of male characteristics
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corpora = bodies
cavernosa = cavernous
Table 35.4 Selected Androgens and Anabolic Steroids
Drug
Route and Adult Dose
Remarks
fluoxymesterone (Halotestin)
PO: 5 mg one to four times per day
Replacement therapy for deficiency of endogenous testosterone, primary and secondary hypogonadism, or delayed puberty
methyltestosterone (Android, Testred, Virilon)
PO: 10-50 mg/day Buccal: 5-25 mg/day
Primary hypogonadism, testicular failure, hypogonadotropic hypogonadism, and delayed puberty
nandrolone (Durabolin, Hybolin)
IM: 50-200 mg/week
Management of anemia due to renal insufficiency, to increase hemoglobin and red cell mass
oxandrolone (Oxandrin)
PO: 2.5-20 mg/day divided bid-qid for 2-4 weeks
To promote weight gain in debilitated patients and for the relief of the bone pain accompanying osteoporosis
oxymetholone (Anadrol-50)
PO: 1-5 mg/kg/day
Treatment of anemias caused by deficient red cell production, aplastic anemias, and myelofibrosis
***testosterone (buccal: Striant); (transdermal patch: Androderm); (topical gels: Androgel, Fortesta, Testim); (implantable pellets: Testopel)
Buccal: 30 mg/12 hours
Transdermal: Apply 1-2 patches daily
(max: 5 mg/day)
Gel: Apply 5 g daily (max 10 g)
IM: 50-400 mg every 2-4 weeks
Pellets: 150-450 mg every 6 months (each pellet
is 75 mg)
Primary therapy is for delayed puberty and hypogonadism; other indications are described in the Prototype Drug feature
testosterone cypionate (Depo-Testosterone)
IM: 50-400 mg every 2-4 weeks
Replacement therapy for deficiency of endogenous testosterone
testosterone enanthate (Delatestryl)
IM: 50-400 mg every 2-4 weeks
Replacement therapy for deficiency of endogenous testosterone, primary hypogonadism, secondary hypogonadism, and delayed puberty
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Prototype Drug: *** Testosterone
Therapeutic Class: Male hypogonadism drug Pharmacologic Class: Androgen
Actions and Uses: The primary therapeutic use of testosterone is for the treatment of hypogonadism in men. The administration of testosterone to young men who have an abnormally delayed puberty will stimulate normal secondary sex characteristics to appear, including enlargement of the sexual organs, facial hair, and a deepening of the voice. In adult men, testosterone administration will increase libido and restore masculine characteristics that may be deficient.
Adverse Effects and Interactions: An obvious adverse effect of testosterone therapy is virilization, or appearance of masculine characteristics. Salt and water are often retained, causing edema. Liver damage is a rare, although potentially serious, adverse effect. Acne and skin irritation are common during therapy.
Testosterone interacts with many drugs. For example, when taken with oral anticoagulants, testosterone may increase hypoprothrombinemia. Insulin requirements may decrease, and the risk of liver toxicity may increase when used with echinacea.
BLACK BOX
Virilization in women and children may occur following secondary exposure. Signs of virilization may include any of the following: deepening of the voice, hirsutism, oily skin, and male-pattern baldness.
ERECTILE DYSFUNCTION
Core Concept 35.7***
Erectile dysfunction is a common disorder successfully treated with drug therapy.
Penile erection has both neuromuscular and vascular components. Autonomic nerves dilate arterioles leading to the major erectile tissues of the penis, called the corpora cavernosa. The corpora have vascular spaces that fill with blood to cause rigidity. In addition, constriction of veins draining blood from the corpora allows the penis to remain rigid long enough for successful penetration. After ejaculation, the veins dilate, blood leaves the corpora, and the penis quickly loses its rigidity. Organic causes of erectile dysfunction may include damage to the nerves or blood vessels involved in the erection reflex.
Erectile dysfunction, or impotence, is a common disorder in men. The defining characteristic of this condition is the consistent inability to either obtain an erection or to sustain an erection long enough to achieve successful intercourse.
The incidence of erectile dysfunction increases with age, although it may occur in an adult male of any age. Certain diseases, most notably atherosclerosis, diabetes, kidney
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disease, stroke, and hypertension, are associated with a higher incidence of the condition. Smoking increases the risk of erectile dysfunction. Psychogenic causes may include depression, fatigue, guilt, or fear of sexual failure. A number of common drugs cause impotence as an adverse effect, including thiazide diuretics, phenothiazines, selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants (TCAs), beta- and alpha-adrenergic blockers, and angiotensin-converting enzyme (ACE) inhibitors. Low testosterone secretion can cause an inability to develop an erection due to loss of libido.
The development of sildenafil (Viagra), an inhibitor of the enzyme phosphodiesterase-5 (PDE-5), revolutionized the medical therapy of erectile dysfunction. The PDE-5 inhibitors do not cause an erection; they merely enhance the erection resulting from physical contact or other sexual stimuli by increasing blood flow and maintaining relaxation of the smooth muscle in the penis.
Three additional PDE-5 inhibitors have been approved by the U.S. Food and Drug Administration (FDA). Vardenafil (Levitra) acts by the same mechanism as sildenafil but has a faster onset and slightly longer duration of action. Tadalafil (Cialis) acts within 30 minutes and has a prolonged duration lasting from 24 to 36 hours. Tadalafil is also used for the treatment of benign prostatic hyperplasia (BPH). The newest of the drugs in this class, avanafil (Stendra), has the same properties as the others but is claimed to have a faster onset of action. Drugs for erectile dysfunction are listed in Table 35.5.
CONCEPT REVIEW 35.3
*Why do you think that sildenafil is used to treat erectile dysfunction instead of testosterone?
Table 35.5 Drugs for Erectile Dysfunction
Drug
Route and Adult Dose
Remarks
avanafil (Stendra)
PO: 100 mg approximately 30 minutes before intercourse (max: 200 mg once per day)
The PDE-5 inhibitors do not cause an erection; they merely enhance the erection by increasing blood flow and maintaining relaxation of the smooth muscle in the penis. These drugs alter the body’s response to sexual stimulation by enhancing the effect of nitric oxide, a chemical that is normally released during stimulation. Nitric oxide causes relaxation of the muscles in the penis, which allows for better blood flow to the penis.
sildenafil (Viagra)
PO: 50 mg approximately 30-60 minutes before intercourse (max: 100 mg once per day)
tadalafil (Cialis)
PO: 10 mg approximately 30 minutes before intercourse (max: 20 mg once per day) Once-daily dosing: 2.5-5 mg daily
vardenafil (Levitra, Staxyn)
PO (film coated tablet or orally disintegrating tablet): 10 mg approximately 1 hour before intercourse (max: 20 mg/day)
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Prototype Drug: *** Sildenafil (Viagra)
Therapeutic Class: Drug for erectile dysfunction Pharmacologic Class: Phosphodiesterase-5 inhibitor
Actions and Uses: Sildenafil acts by dilating blood vessels (vasodilation) and relaxing the erectile tissues in the penis, called the corpora cavernosa, which allows increased blood flow into the organ. The increased blood flow results in a firmer and longer-lasting erection in about 70% of men taking the drug.
Adverse Effects and Interactions: The most serious adverse effects with sildenafil occur in men who are concurrently taking organic nitrates, common drugs that also dilate blood vessels and are used in the therapy of angina. The combination of these drugs causes a marked increase in vasodilation, causing a drop in blood pressure and decreased blood flow to the heart, possibly causing a heart attack. Minor adverse effects include headache, flushing, and nasal congestion.
Cimetidine, erythromycin, and ketoconazole increase serum levels of sildenafil and require lower drug doses. Protease inhibitors (ritonavir, amprenavir, and others) will cause increased sildenafil levels, which may lead to toxicity. Rifampin may decrease sildenafil levels, leading to decreased effectiveness.
BENIGN PROSTATIC HYPERPLASIA *** Core Concept 35.8
In its early stages, benign prostatic hyperplasia is successfully treated
Benign prostatic hyperplasia (BPH) is the most common benign neoplasm in men. It is characterized by enlargement of the prostate gland. This decreases the outflow of urine by obstructing the urethra, causing difficult urination
*** Lifespan and Diversity
Erectile dysfunction affects about one in four men older than age 65.
[sidebar]
benign= mild
hyper = over
plasia = growth
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noct = nighttime
uria = urine
***Lifespan and Diversity
BPH affects 50% of men older than age 60 and 90% of men older than age 80.
Symptoms include increased urinary frequency (usually with small amounts of urine), increased urgency to urinate, excessive nighttime urination (nocturia), decreased force of the urine stream, and a sensation that the bladder is not completely empty. BPH is illustrated in Figure 35.3.
Early in the course of the disease, drug therapy may relieve some symptoms. Only a few drugs are available for the treatment of BPH. These drugs are listed in Table 35.6.
Table 35.6 Drugs for Benign Prostatic Hyperplasia
Drug
Route and Adult Dose
Remarks
ALPHA1-ADRENERGIC BLOCKERS
alfuzosin (UroXatral)
PO: 10 mg/day (max: 10 mg/day)
When activated, the alpha,-adrenergic receptors compress the urethra and provide resistance to urine outflow from the bladder. Alpha, blockers counter urethral compression.
doxazosin (Cardura)
PO (Regular-release): 1-8 mg/day (max: 8 mg/day)
doxazosin (Cardura XL)
PO (Extended-release): 4-8 mg/day (max: 8 mg/day)
silodosin (Rapaflo)
PO: 8 mg once daily
tamsulosin (Flomax)
PO: 0.4 mg 30 minutes after a meal (max: 0.8 mg/day)
terazosin (Hytrin)
PO: Start with 1-5 mg/day (max: 20 mg/day)
5-ALPHA-REDUCTASE INHIBITORS
dutasteride (Avodart)
PO: 0.5 mg once daily
5-Alpha-reductase inhibitors block the action of the enzyme that converts testosterone into dihydrotestosterone, a promoter of prostate growth. The size of the prostate is therefore reduced.
***finasteride (Proscar)
PO: 5 mg once daily
FIGURE 35.3 Benign prostatic hyperplasia (BPH): (a) normal prostate with penis; (b) benign prostatic hyperplasia.
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Prototype Drug: *** Finasteride (Proscar)
Therapeutic Class: Drug for benign prostatic hyperplasia Pharmacologic Class: 5-Alpha-reductase enzyme inhibitor
Actions and Uses: Finasteride acts by inhibiting 5-alpha reductase, the enzyme responsible for converting testosterone to one of its metabolites. This metabolite causes growth of prostate cells and promotes enlargement of the gland. Finasteride shrinks enlarged prostates and helps to restore urinary function. It is most effective in patients with larger prostates. This drug is also marketed as Propecia, which is prescribed to promote hair regrowth in patients with male-pattern baldness.
Doses of finasteride are five times higher when prescribed for BPH than when prescribed for baldness.
Adverse Effects and Interactions: Finasteride causes various types of sexual dysfunction in some patients, including impotence, diminished libido, and ejaculatory dysfunction.
No clinically significant drug interactions have been established. Use with caution with herbal supplements. For example, saw palmetto may increase the effects of finasteride.
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Patients Need to Know
Patients treated for purposes of regulating reproductive processes need to know the following:
Regarding Oral and Extended-release Contraceptives
1. If taking or applying contraceptives, schedule frequent medical checkups. Take blood pressure periodically and report any persistent changes to a healthcare provider.
2. Discontinue OCs, estrogen, or progestins immediately if pregnancy is suspected. Continued use may injure the fetus.
3. Inform the healthcare provider if contraceptives are taken or applied. Some drugs decrease their effectiveness and this could result in pregnancy. Drugs that reduce effectiveness of contraceptives Include several common antibiotics and antiseizure medications.
4. A balanced diet is Important when taking OCs, because these drugs may lower levels of folic acid and vitamin B6.
Regarding Hormone Replacement Therapy
5. Before beginning HRT, a baseline mammogram should be performed. Monthly breast self-examinations should be conducted in addition to an annual exam by a healthcare provider.
Regarding Erectile Dysfunction Medications
6. If taking antihypertensive drugs, monitor blood pressure carefully when taking sildenafil. An Increased risk of hypotension is possible.
Regarding Androgens
7. When taking androgens, expect virilization to occur. Prolonged erections, known as priapisms, should be reported to a healthcare provider immediately. This is a sign of overdose, and permanent damage to the penis may result.
Chapter Review Core Concepts Summary
35.1 The hypothalamus, pituitary, and gonads control reproductive function in both men and women.
Estrogens are secreted by ovarian follicles and are responsible for maturation of the sex organs and the secondary sex characteristics of the female. Progestins are secreted by the corpus luteum and prepare the endometrium for implantation. Testosterone is secreted by the testes and is responsible for the growth and maintenance of the male reproductive system. The sex hormones are controlled by GnRH from the hypothalamus and FSH and LH from the pituitary gland.
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35.2 Oral contraceptives and extended-release formulations are drugs used in low doses to prevent pregnancy.
Most hormonal contraceptives contain low doses of estrogens and progestins. Nearly 100% effective, these drugs prevent conception by blocking ovulation. Long-term formulations offer greater flexibility of administration. Oral and extended-duration contraceptives are safe for the majority of women, but they have some potentially serious adverse effects. Antibiotics, antifungals, barbiturates, and antiseizure medications can interfere with the effectiveness of hormonal agents.
35.3 Hormone replacement therapy provides estrogen to treat postmenopausal symptoms, but benefits may not outweigh risks.
Estrogen-progestin combinations are used for hormone replacement therapy during and after menopause. Their long-term use may have serious adverse effects, including increased risk of MI, stroke, breast cancer, and blood clots.
35.4 Conjugated estrogens and progestins are prescribed for dysfunctional uterine bleeding, endometrial cancer, and postmenopausal symptoms.
Dysfunctional uterine bleeding is often the result of an imbalance between progesterone and estrogen secretion. Administration of progestins may reestablish a normal cyclic menstrual pattern. Progestins are also used to treat endometrial cancer. Conjugated estrogens treat postmenopausal symptoms.
35.5 Oxytocics and tocolytics are drugs that influence uterine contractions and labor.
Oxytocics are drugs that stimulate uterine contractions and induce labor. Oxytocin, methylergonovine (ergot alkaloid), and prostaglandins are examples of uterine stimulants. Tocolytics slow uterine contractions to delay labor.
35.6 Androgens are used to treat hypogonadism in males.
Administration of testosterone promotes the appearance of masculine characteristics, a desirable action in men with hypogonadism. Anabolic steroids are testosterone-like drugs that may produce serious and permanent adverse effects.
35.7 Erectile dysfunction is a common disorder successfully treated with drug therapy.
Erectile dysfunction is a common disorder with many possible physiologic and psychogenic causes. Sildenafil is effective at promoting more rigid and longer-lasting erections. It is contraindicated in patients taking organic nitrates.
35.8 In its early stages, benign prostatic hyperplasia is successfully treated.
BPH results in urinary difficulties that may be treated by drug therapy or surgery. Alpha,-blockers relax smooth muscle in the urethra to promote urine flow. 5-Alpha-reductase inhibitors reduce the size of the prostate to reduce pressure on the urethra. Goals are to minimize urinary obstruction, increase urine flow, and minimize complications.
REVIEW Questions
Answer the following questions to assess your knowledge of the chapter material, and go back and review any material that is not clear to you.
1. The healthcare provider tells the patient that the type of birth control where the estrogen level remains constant throughout the cycle but the progestin level increases toward the end of the menstrual cycle is called:
1. Monophasic.
2. Biphasic.
3. Triphasic.
4. Quadriphasic.
2. Before a patient begins taking sildenafil (Viagra), the nurse asks which of the following questions?
1. “Are you currently taking any medications for angina?”
2. “Do you have a history of diabetes?”
3. “Have you ever had an allergic reaction to dairy products?”
4. “Have you ever been treated for migraine headaches?”
3. When planning patient care, the nurse understands that medroxyprogesterone (Prempro) would be contraindicated for which of the following patients?
1. A 37-year-old woman with dysfunctional uterine bleeding
2. A 65-year-old woman diagnosed with metastatic uterine cancer
3. A 40-year-old woman with a history of deep vein thrombosis
4. A healthy 21-year-old who needs birth control
4. The patient states she had sexual intercourse yesterday and is concerned she may be pregnant. She is requesting emergency prevention. The healthcare provider knows that which of the following drugs may be ordered?
1. Oxytocin
2. Levonorgestrel
3. Medroxyprogesterone
4. Magnesium sulfate
5. The patient is being given oxytocin (Pitocin). The nurse evaluates her response to the drug, looking specifically for the possibility of: (Select all that apply.)
1. Uterine rupture.
2. Seizures.
3. Fetal dysrhythmias.
4. Hypotension.
5. Hypertension.
6. A patient, seeking information about testosterone replacement therapy, asks about its application and possible complications. The nurse informs him that complications of testosterone therapy may include:
1. Renal failure.
2. Hepatic failure.
3. Decreased cholesterol levels.
4. Maturation of male sex organs.
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7. Your patient states that she has forgotten to take her birth control pills for the last 2 days. You should instruct her to:
1. Take her missed pills immediately.
2. Get back on schedule as soon as possible.
3. Use additional birth control measures until a regular schedule is established with the birth control pills.
4. Get a home pregnancy kit.
8. The healthcare provider ordered testosterone cypionate (Depo-Testosterone), 50 mg, IM, every 2 weeks. The label on the vial states 100 mg/mL. How many milligrams will the nurse administer over an 8-week period of time?
1. 100 mg
2. 400 mg
3. 300 mg
4. 200 mg
9. A patient states that she is experiencing menopausal symptoms and asks for advice regarding hormone replacement therapy (HRT). The healthcare provider’s best response is:
1. “HRT is dangerous and should never be prescribed.”
2. “HRT is perfectly safe, with no risks.”
3. “You are not a candidate for HRT.”
4. “You need to discuss risks versus benefits of HRT with your healthcare provider.”
10. Your patient with benign prostatic hyperplasia is complaining of feeling like he “cannot empty his bladder.” You suspect that the healthcare provider will order which of the following?
1. Finasteride (Propecia)
2. Sildenafil (Viagra)
3. Estrogen
4. Finasteride (Proscar)
CASE STUDY Questions
[Image: Ms. Marge Philips.]
Remember Ms. Philips, the patient introduced at the beginning of the chapter? Now read the remainder of the case study. Based on the information you have learned in this chapter, answer the questions that follow.
Ms. Marge Philips, a 42-year-old female, enters the clinic with complaints of lower abdominal pain and irregular menstrual bleeding with prolonged menstruation. Blood pressure and pulse are slightly elevated. She states that she has had problems with frequently being tired. Other than her current complaint, she has no health problems or concerns. Ms. Philips last physical exam was 1 year ago. She is diagnosed with dysfunctional uterine bleeding and is prescribed Depo-Provera.
1. After the diagnosis is confirmed, the nurse knows that_is a common method of treating dysfunctional uterine bleeding.
1. Use of condoms
2. Visiting the doctor only when the pain gets really bad
3. Possible use of oral contraceptives
4. Screening of sexual partner
2. In order to determine if Ms. Philips is a good candidate for the medication, Depo-Provera, the nurse asks Ms. Philips if she:
1. Has diabetes.
2. Is planning on losing weight.
3. Has a diet high in protein.
4. Is planning on becoming pregnant.
3. Ms. Philips is to begin the oral contraceptive, Depo-Provera, as a means to control the uterine bleeding. The nurse informs her: (Select all that apply.)
1. That smoking increases the risk of serious cardiovascular adverse effects.
2. That it is okay to miss taking the medication for several days in a row.
3. To notify her healthcare provider if two or more consecutive periods are missed.
4. That caffeine will be beneficial.
4. The nurse also informs Ms. Philips that the adverse effects of Depo-Provera are: (Select all that apply.)
1. Weight loss.
2. Breast tenderness.
3. Loss of appetite.
4. Breakthrough bleeding.
Answers and complete rationales for the Review and Case Study Questions appear in Appendix A.
REFERENCE
Herdman, T. H., & Kamitsuru, S. (Eds.). (2014). NANDA International nursing diagnoses: Definitions and classification, 2015-2017. Oxford, United Kingdom: Wiley-Blackwell
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SELECTED BIBLIOGRAPHY
Bedell, S., Nachtigall, M., & Naftolin, F. (2014). The pros and cons of plant estrogens for menopause. The Journal of Steroid Biochemistry and Molecular Biology, 139,225-236. doi:10.1016/j.jsbmb.2012.12.004
Centers for Disease Control and Prevention (2015). Contraceptive use. Retrieved from http://www.cdc.gov/nchs/fastats/contraceptive. htm
Centers for Disease Control and Prevention. (2016). Prostate cancer. Retrieved from http://www.cdc.gov/cancer/prostate
Ensari, T. A., & Pal, L. (2015). Update on menopausal hormone therapy. Current Opinion in Endocrinology Diabetes and Obesity. 22, 475-482. doi:10.1097/MED.0000000000000207
Estephan, A. (2015). Dysfunctional uterine bleeding in emergency medicine. Retrieved from http://emedicine.medscape.com/ article/795587-overview#a0104
Hawksworth, D. J., & Burnett, A. L. (2015). Pharmacotherapeutic management of erectile dysfunction. Clinical Pharmacology and Therapeutics. 98, 602-610. doi:10.1002/cpt.261
Levin, E. R., & Hammes, S. R. (2011). Estrogens and progestins. In L. L. Brunton, B. A. Chabner, & B. C. Knollman (Eds.), Goodman and Gilman’s the pharmacological basis of therapeutics (12th ed., pp. 1163-1194). New York, NY: McGraw-Hill.
Nappi, R. E., & Cucinella, L. (2015). Advances in pharmacotherapy for treating female sexual dysfunction. Expert Opinion on Pharmacotherapy, 16, 875-887. doi:10.1517/14656566.2015.1020791
Ribaudo, G., Pagano, M. A., Bova, S., & Zagotto, G. (2016). New therapeutic applications of phosphodiesterase 5 inhibitors (PDE5-Is). Current Medicinal Chemistry, 23,1239-1249 doi:10.2174/0929867323 666160428110059
Schimmer, B. P., & Parker, K. L. (2011). Contraception and the pharmacotherapy of obstetrical and gynecological disorders. In L. L. Brunton, B. A. Chabner, & B. C. Knollman (Eds.), Goodman and Gilman’s the pharmacological basis of therapeutics (12th ed., pp. 1833-1852). New York, NY: McGraw-Hill.
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Unit 7 The Skeletal System, Integumentary System, and Eyes and Ears
Unit Contents
Chapter 36 Drugs for Bone and Joint Disorders
Chapter 37 Drugs for Skin Disorders
Chapter 38 Drugs for Eye and Ear Disorders
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Chapter 36 Drugs for Bone and Joint Disorders
[Image: Mr. Steven Hurtt.]
“I can’t even work in the garden anymore. My joints ache so badly, and I don’t understand what’s going on with my big toe.”
Mr. Steven Hurtt
Core Concepts Drug Snapshot
36.1 Adequate levels of calcium, vitamin D, parathyroid hormone, and calcitonin are necessary for bone and body homeostasis.
36.2 Hypocalcemia is a serious condition that requires immediate therapy.
36.3 Osteomalacia and rickets are successfully treated with calcium salts and vitamin D supplements.
36.4 Treatment for osteoporosis includes calcitonin, selective estrogen-receptor modulators, and bisphosphonates.
36.5 Treatment for Paget disease includes biologic therapies and bisphosphonates.
36.6 Analgesics and anti-inflammatory drugs are important components of pharmacotherapy for osteoarthritis.
36.7 Immunosuppressants and disease-modifying drugs are additional therapies used to treat rheumatoid arthritis.
36.8 Pharmacotherapy for gout requires drugs that control uric acid levels.
Drug Snapshot
The following drugs are discussed in this chapter:
Drug Classes
Prototype Drugs I
DRUGS FOR HYPOCALCEMIA
Calcium supplements
***calcium salts
DRUGS FOR METABOLIC BONE DISORDERS
Vitamin D therapy
***calcitriol (Calcijex, Rocaltrol)
Selective estrogen-receptor modulators (SERMs)
***raloxifene (Evista)
Bisphosphonates
***alendronate (Fosamax)
DRUGS FOR JOINT DISORDERS
Disease-modifying antirheumatic drugs (DMARDs)
***hydroxychloroquine (Plaquenil)
Drugs for gout
***allopurinol (Lopurin, Zyloprin)
Learning Outcomes
After reading this chapter, the student should be able to:
1. Describe the roles of calcium, vitamin D, parathyroid, and calcitonin in maintaining
2. Explain the importance of treating hypocalcemia, bone health.
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3. Describe the pharmacologic management of disorders caused by calcium and vitamin D deficiency such as osteomalacia and rickets.
4. Explain drug treatments for weak and fragile bones such as osteoporosis and Paget disease.
5. Explain drug treatments directly related to weak bones and joints such as osteoarthritis, rheumatoid arthritis, and gout.
Key Terms
acute gouty arthritis (ah-CUTE GOW-tyare-THRYE-tis)
autoantibodies (AW-to w-AN N -tee- BAH -dees)
biologic response modifiers (BEYE-oh-LAH- jick)
bisphosphonates (bis-FOSS-foh-nayts)
bone deposition
bone resorption (ree-SORP-shun)
calcifediol (kal-SIF-eh-DYE-ol)
calcitonin (kal-sih-TOH-nin)
calcitriol (kal-si-TRY-ol)
cholecalciferol (KOH-lee-kal-SIF-er-ol)
disease-modifying antirheumatic (ANTY-roo-MAT-ik)
drugs (DMARDs)
gout (GOWT)
metabolic bone disorders (meh-tuh-BAHL-ik)
osteoarthritis (OA) (OSS-tee-oh-are-THRYE-tis)
osteomalacia (OSS-tee-oh-muh-LAY-shee-uh)
osteoporosis (OSS-tee-oh-poh-ROH-sis
Paget disease (PAH-jet)
rheumatoid arthritis (RA) (ROO-mah-toydare-THRYE-tis)
selective estrogen-receptor modulators (SERMs)
uricosurics (YOUR-ik-cose-youriks)
The skeletal system and joints are at the core of movement and must be free from any defect that would destabilize the other body systems. For nerves, muscles, and bones to function well, the body needs adequate levels of calcium. Disorders associated with bones and joints affect a patient’s ability to fulfill daily activities and lead to immobility.
This chapter focuses on the pharmacotherapy of skeletal disorders such as osteomalacia, osteoporosis, and Paget Disease, described as metabolic bone disorders, and the joint disorders, arthritis and gout. It stresses the importance of calcium balance and the action of vitamin D as they relate to the proper structure and function of bones and joints. Drugs are important because major mobility problems would occur without intervention.
*** Core Concept 36.1
Adequate levels of calcium, vitamin D, parathyroid hormone, and calcitonin are necessary for bone and body homeostasis.
As shown in Figure 36.1, calcium levels in the bloodstream are controlled by two endocrine glands: the parathyroid glands and the thyroid gland. The parathyroid glands secrete parathyroid hormone (PTH), and the thyroid gland secretes calcitonin. PTH stimulates bone cells called osteoclasts. Osteoclasts break down bone tissue into its mineral components, a process called bone resorption. Once the bone is broken down, calcium is released for transport in the bloodstream and is used elsewhere in the body. The opposite of this process is bone deposition, or bone building. Calcitonin stimulates the building of bones by adding calcium to bone tissue.
Vitamin D is unique among vitamins in that the body is able to synthesize it from precursor molecules. The inactive form of vitamin D, called cholecalciferol, is synthesized in the skin from cholesterol. Exposure of the skin to sunlight or ultraviolet light increases the level of cholecalciferol in the bloodstream. Cholecalciferol can also be obtained from milk or other foods that are fortified with vitamin D. Figure 36.2 illustrates the metabolism of vitamin D.
Once cholecalciferol is absorbed or formed in the body, it is converted to an intermediate vitamin form called calcifediol. Enzymes in the kidneys metabolize calcifediol to calcitriol, the active form of vitamin D. Patients with extensive kidney disease are unable to synthesize adequate levels of calcitriol. The primary function of calcitriol is to increase calcium absorption from the gastrointestinal (GI) tract. Dietary calcium is absorbed better in the presence of PTH and active vitamin D.
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hyper = elevated
hypo = lowered
calc = calcium
emia = blood level
FIGURE 36.1 (a) Parathyroid hormone (PTH); (b) calcitonin action.
The importance of proper calcium balance in the body cannot be overstated. Calcium ions influence the excitability of all neurons. When calcium concentrations are too high (hypercalcemia), sodium permeability decreases across cell membranes. This is dangerous because nerve conduction depends on the proper influx of sodium into cells. When calcium levels in the bloodstream are too low (hypocalcemia), cell membranes become hyperexcitable. If hypocalcemia becomes severe, seizures or muscle spasms may result. Calcium is also important for the normal functioning of other body processes such as blood coagulation and neurotransmitter release, and stability of the entire skeletal system.
Core Concept 36.2*** HYPOCALCEMIA
Hypocalcemia is a serious condition that requires immediate therapy.
Hypocalcemia, or lowered levels of calcium in the blood, is associated with a range of conditions, including poor nutrition, seizures, muscle spasms, and endocrine and bone disorders. Hypocalcemia is not a disease, but a sign of underlying pathology; therefore, diagnosis of the cause of hypocalcemia is essential. One common cause is hyposecretion of PTH, which occurs when the thyroid and parathyroid glands are surgically removed. Digestive-related malabsorption disorders and vitamin D deficiencies also result in hypocalcemia. In cases of hypocalcemia, healthcare providers should assess for the adequate intake of calcium-containing foods. With hypocalcemia, numbness and tingling of the extremities may occur, and convulsions are possible. Symptoms of hypocalcemia are nerve and muscle excitability. Muscle twitching, tremor, or cramping may be evident. A patient may be confused or behave abnormally.
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FIGURE 36.2 Pathway for vitamin D activation.
Therapies for calcium disorders involve calcium salts, vitamin D supplements, bisphosphonates, and miscellaneous drugs. Severe hypocalcemia requires IV administration of calcium salts, whereas less severe hypocalcemia can often be reversed with oral supplements.
OSTEOMALACIA AND RICKETS ***Core Concept 36.3
Osteomalacia and rickets are successfully treated with calcium salts and vitamin D supplements
Osteomalacia, referred to as rickets in children, is a metabolic bone disorder characterized by softening of bones without alteration of basic bone structure, although with noticeable deformities observed in the chest and leg areas. The cause of osteomalacia and rickets is a lack of vitamin D and calcium in the diet, usually as a result of kidney failure or malabsorption of calcium from the GI tract.
Signs and symptoms of osteomalacia include hypocalcemia, muscle weakness, muscle spasms, and diffuse bone pain, especially in the hip area. Patients may also experience pain in the arms, legs, and spinal column. Classic signs of rickets in children include bowlegs and a pigeon breast. Children may also develop a slight fever and become restless at night.
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Tests performed to verify osteomalacia include bone biopsy; bone radiographs; computerized tomography (CT) scan of the vertebral column and other bone density tests; and determination of serum calcium, phosphate, and vitamin D levels. Many of these tests are routine for bone disorders and are performed as needed to determine the extent of bone health.
Drug therapy for osteomalacia consists of calcium salts and vitamin D supplements. Drugs used for treating metabolic bone disorders, including hypocalcemia, osteomalacia, and rickets, are shown in Table 36.1. In extreme cases, surgical correction of disfigured limbs may be required.
Most calcium salts are in the form of complexed calcium, meaning that elemental calcium is bound to an array of surrounding molecules. Calcium salts are often compared on the basis of their ability to release elemental calcium into the bloodstream. The supplement is more potent when the calcium product has a greater ability to release elemental calcium into the bloodstream. A milliequivalent (mEq) is the unit used to describe the amount of electrolyte available for absorption. Therefore, the higher the mEq, the more potent the calcium salt. Elemental calcium may be obtained from dietary sources such as dark green vegetables, canned salmon, and fortified products, including tofu, orange juice, and milk.
Inactive, intermediate, and active forms of vitamin D are also available. The amount of vitamin D a patient needs will often vary depending on how much he or she is exposed to sunlight. After age 70, the average recommended intake of vitamin D increases from 400 to 600 units per day. A laboratory test may be ordered to determine proper levels of vitamin D. Because vitamin D is needed to absorb calcium from the GI tract, many supplements combine vitamin D and calcium into a single tablet.
CONCEPT REVIEW 36.1
* Identify the major drug therapies used for hypocalcemia, osteomalacia, and rickets.
Table 36.1 Calcium Salts and Vitamin D Therapy
Drug
Route and Adult Dose
Remarks
CALCIUM SALTS (The higher the mEq, the more potent the calcium salt)
calcium acetate (PhosLo)
PO: 1-2 g bid-tid
One gram calcium acetate equals 250 mg (12.6 mEq) elemental calcium; phosphate binder used to treat hypophosphatemia in kidney dialysis patients
calcium carbonate (Rolaids, Turns, others)
PO: 1-2 g bid-tid
One gram calcium carbonate equals 400 mg (20 mEq) elemental calcium
calcium chloride
IV: 0.5-1 g by slow Infusion (1 mL/min)
One gram calcium chloride equals 272 mg (13.6 mEq) elemental calcium; may be irritating to body tissues
calcium citrate (Citracal)
PO: 1-2 g bid-tid
One gram calcium citrate equals 210 mg (12 mEq) elemental calcium
calcium gluconate (Kalcinate)
PO: 1-2 g bid-tid
IV: 0.5-4 g by slow infusions (1 g/hour)
One gram calcium gluconate equals 90 mg (4.5 mEq) elemental calcium
calcium lactate (Cal-Lac)
PO: 100-200 mg tid with meals
One gram calcium lactate equals 130 mg (6.5 mEq) elemental calcium
calcium phosphate tribasic (Posture)
PO: 1-2 g bid-tid
One gram calcium phosphate equals 390 mg (19.3 mEq) elemental calcium
VITAMIN D SUPPLEMENTS
***calcitriol (Calcijex, Rocaltrol)
PO: 0.25 meg/day
IV: 0.5 meg three times per week at the end of dialysis
For hypocalcemia in chronic renal failure and with hypoparathyroidism
doxercalciferol (Hectorol)
PO: 10 meg, three times per week (max: 60 meg/week) IV: 4 meg, three times per week at the end of dialysis (max: 18 meg/week)
For hyperparathyroidism in patients with chronic kidney disease or in patients on dialysis
ergocalciferol (Calciferol, Drisdol)
PO: 25-125 meg/day for 6-12 weeks
For osteomalacia; also used for vitamin D-dependent rickets and hypoparathyroidism
paricalcitol (Zemplar)
PO: 1 meg/day or 4 meg three times per week
IV: 0.04-0.1 mcg/kg, every other day during dialysis
(max: 24 mcg/kg)
For the prevention and treatment of hyperparathyroidism in patients with chronic kidney disease
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Prototype Drug: *** Calcium salts
Therapeutic Class: Calcium supplement for hypoparathyroidism, osteoporosis, and rickets Pharmacologic Class: Reverses hypocalcemia
Actions and Uses: Calcium salts are used to correct hypocalcemia and to treat osteoporosis and rickets. The objective of calcium therapy is to return serum levels of calcium to normal. People at high risk for developing these conditions include postmenopausal women, those with little physical activity over a prolonged period, and patients taking certain medications such as corticosteroids, immunosuppressive drugs, and some antiseizure medications.
Adverse Effects and Interactions: The most common adverse effect of calcium salts is hypercalcemia, which is brought on by taking too much of these supplements. Symptoms include drowsiness, lethargy, weakness, headache, anorexia, nausea and vomiting, increased urination, and thirst. IV administration of calcium may cause hypotension, bradycardia, dysrhythmia, and cardiac arrest.
When taking other medications, patients should wait for at least 1 hour before taking calcium supplements or medications such as Mylanta and Maalox. Magnesium antacids or supplements may compete with GI absorption. Calcium salts taken with cardiac glycosides increases the risk of dysrhythmias. Calcium decreases the absorption of tetracyclines.
[box]
Prototype Drug: *** Calcitriol (Calcijex, Rocaltrol)
Therapeutic Class: Drug for osteoporosis, osteomalacia, and rickets Pharmacologic Class: Vitamin D, reverses hypocalcemia
Actions and Uses: Calcitriol is the active form of vitamin D and is available in both oral and IV formulations. It promotes the intestinal absorption of calcium and elevates serum levels of calcium. This medication is used when patients have impaired kidney function or have hypoparathyroidism. Calcitriol reduces bone resorption and is useful in treating rickets. The effectiveness of calcitriol depends on the patient receiving an adequate amount of calcium; therefore, it is usually prescribed in combination with calcium supplements.
Adverse Effects and Interactions: Common adverse effects include hypercalcemia, headache, weakness, dry mouth, thirst, increased urination, and muscle or bone pain. Thiazide diuretics may increase the effects of vitamin D, causing hypercalcemia. Too much vitamin D may cause dysrhythmias in patients who are receiving cardiac glycosides. Magnesium antacids or supplements should not be given together with calcitriol because of the increased risk of hypermagnesemia.
OSTEOPOROSIS ***Core Concept 36.4
Treatment for osteoporosis includes calcitonin, selective estrogen-receptor modulators, and bisphosphonates.
Osteoporosis is the most common metabolic bone disorder. This disorder is usually asymptomatic until the bones become brittle enough to fracture or a vertebra collapses. In some cases, a lack of dietary calcium and vitamin D contribute to bone deterioration. In other cases, osteoporosis is due to disrupted bone homeostasis.
Simply stated, the homeostatic imbalance with osteoporosis is that bone resorption outpaces bone deposition, and patients begin to develop weak bones. This is generally considered an aging disorder. Following are the risk factors for osteoporosis:
* Postmenopausal status
* High alcohol or caffeine consumption
* Anorexia nervosa
* Tobacco use
* Physical inactivity
* Testosterone deficiency, particularly in older men
* Lack of adequate vitamin D or calcium in the diet
* Drugs such as corticosteroids, some anticonvulsants, and immunosuppressants that lower calcium levels in the bloodstream.
The most common risk factor associated with the development of osteoporosis is the onset of menopause. When women reach menopause, estrogen secretion declines and bones become weak and fragile. One theory to explain this occurrence is that normal levels of estrogen may limit the lifespan of osteoclasts, the bone cells that resorb bone. When estrogen levels become low, osteoclast activity is no longer controlled, and bone demineralization accelerates, resulting in loss of bone density. In women with osteoporosis, fractures often occur in the hips, wrists, forearms, or spine. The metabolism of calcium in osteoporosis is illustrated in Figure 36.3.
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FIGURE 36.3 Calcium metabolism in osteoporosis: (a) bone deposition equals bone resorption; (b) bone resorption outpaces bone deposition.
Many drug therapies are available for osteoporosis. These include calcium and vitamin D therapy, hormone therapy with estrogen, estrogen-receptor modulators, calcitonin, statins, slow-release sodium fluoride, and bisphosphonates. Many of these drug classes are also used for other bone disorders or conditions unrelated to the skeletal system. Selected drugs for osteoporosis and related bone disorders are listed in Table 36.2.
Calcitonin
Calcitonin is a naturally occurring hormone secreted by the thyroid gland when blood calcium becomes elevated. It is involved in the process of bone building by opposing the effects of the PTH and inhibiting osteoclast activity in the bone. As a medication, calcitonin is obtained from salmon and is approved for the treatment of osteoporosis in women who are more than 5 years postmenopausal. It is available by nasal spray or subcutaneous injection. Calcitonin increases bone density and reduces the risk of vertebral fractures. Adverse effects are generally minor; the nasal formulation may irritate the nasal mucosa and allergies are possible. Parenteral forms may produce nausea and vomiting. In addition to treating osteoporosis, calcitonin is indicated for Paget disease and hypercalcemia.
Selective Estrogen-Receptor Modulators
Selective estrogen-receptor modulators (SERMs) bind to estrogen receptors and comprise a class of drugs used in the prevention and treatment of osteoporosis. SERMs may be estrogen agonists or antagonists, depending on the specific drug and the tissue involved. In the uterus and breasts, raloxifene (Evista) blocks estrogen receptors; thus, it has no estrogen-like proliferative effects on these tissues that might promote cancer. It is one of the few drugs available for the prevention of breast cancer in postmenopausal women at high risk for the disease. Evista decreases bone resorption, thus increasing bone density and making fractures less likely. Like estrogen, it has a cholesterol-lowering effect.
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Table 36.2 Bone Resorption Inhibitors and Selected Drugs
Drug
Route and Adult Dose
Remarks
BIOLOGIC THERAPIES
bazedoxifene with conjugated estrogens (Duavee)
PO: 20 mg/0.45 mg (1 tablet) dally
Newer drug to prevent osteoporosis that combines a selective estrogen-receptor modulator with estrogens
calcitonin-salmon (Fortical, Miacalcin)
Hypercalcemia: Subcutaneous/IM: calcitonin-salmon, 4 units/kg bid Osteoporosis: Intranasal: 1 spray/day (200 international units) in one nostril, alternating nostrils each day
Calcium regulating hormone; for hypercalcemia and postmenopausal osteoporosis
cinacalcet (Sensipar)
PO: Start with 30 mg once daily; may increase until target PTH of 150-300 mg/mL (max: 300/day)
For secondary hyperparathyroidism
denosumab (Prolia, Xgeva)
Subcutaneous (Prolia): 60 mg every 6 months
For postmenopausal osteoporosis in women at high risk for fracture (Prolia) or prevention of skeletal-related adverse events in patients with bone metastases (Xgeva)
***raloxifene (Evista)
PO: 60 mg daily
Selective estrogen-receptor modulator (SERM); for prevention and treatment of osteoporosis in postmenopausal women and breast cancer prophylaxis
teriparatide (Forteo)
Subcutaneous: 20 meg/day
PTH (rDNA origin); for osteoporosis in postmenopausal women; for male patients with high risk of fractures
BISPHOSPHONATES
***alendronate (Fosamax)
Osteoporosis treatment: PO: 10 mg daily; Osteoporosis prevention: PO: 5 mg daily; Paget disease: PO 40 mg daily for 6 months
For osteoporosis in men and women; for Paget disease
etidronate (Didronel)
PO: 5-10 mg/kg daily for 6 months or 11-20 mg/kg daily for 3 months
For Paget disease
ibandronate (Boniva)
PO: 2.5 mg daily or 150 mg once monthly
For treatment and prevention of postmenopausal osteoporosis
Pamidronate (Aredia)
IV: 30-90 mg infused over 4-24 hours
For Paget disease and hypercalcemia of malignancy
risedronate (Actonel)
PO: 5 mg daily or 35 mg once weekly or 75 mg daily for 2 consecutive weeks
For prevention and treatment of osteoporosis and Paget disease
tiludronate (Skelid)
PO: 400 mg daily taken with 6-8 ounces of water 2 hours before or after food for 3 months
For Paget disease
zoledronate (Reclast, Zometa): also called zoledronic acid
IV: 4-5 mg, may be repeated in 7 days
For hypercalcemia; treatment of steroid-induced or postmenopausal osteoporosis, bone metastases, and Paget disease
Prototype Drug: *** Raloxifene (Evista)
Therapeutic Class: Treatment of postmenopausal osteoporosis in women Pharmacologic Class: Bone resorption inhibitor, selective estrogen-receptor modulator
Actions and Uses: Raloxifene is a SERM. It decreases bone resorption and increases bone mass and density by acting through the estrogen receptor. Raloxifene is primarily used for the prevention of osteoporosis in postmenopausal women. It is also one of the few drugs used for the prevention of breast cancer in women at high risk for invasive breast cancer. This drug also reduces serum total cholesterol and low-density lipoprotein (LDL) without lowering high-density lipoprotein (HDL) or triglycerides.
Adverse Effects and Interactions: Common adverse effects are hot flashes, migraine headache, flu-like symptoms, endometrial disorder, breast pain, and vaginal bleeding. Patients should not take cholesterol-lowering drugs or estrogen replacement therapy concurrently with this medication.
Absorption is reduced by cholestyramine. Patients taking raloxifene, along with warfarin, should have their prothrombin time (PT) and international normalized ratio (INR) tested when starting or stopping this medication
BLACK BOX WARNING:
Raloxifene increases the risk of venous thromboembolism and death from strokes. Women with a history of venous thromboembolism should not take this drug.
Bisphosphonates
The most common drug class used to treat osteoporosis is the bisphosphonates. These drugs are very similar to pyrophosphate, a natural inhibitor of bone resorption. Bisphosphonates inhibit bone resorption by suppressing osteoclast activity, thereby increasing bone density and reducing the incidence of fractures. Examples include alendronate (Fosamax), etidronate
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(Didronel), ibandronate (Boniva), pamidronate (Aredia), risedronate (Actonel, Atelvia), tiludronate (Skelid), and zoledronate (Reclast, Zometa). Although primarily used to treat osteoporosis in postmenopausal women, drugs in this class are also used to treat Paget disease, osteoporosis in men, hypercalcemia and metastases due to bone cancer, multiple myeloma, and breast cancer. Adverse effects include GI problems such as nausea, vomiting, abdominal pain, and esophageal irritation; therefore, patients are advised to remain in an upright position for 30 minutes after taking these medications. All the bisphosphonates carry a warning that they may rarely cause osteonecrosis, a complete and irreversible destruction of the jawbone. Because these drugs are poorly absorbed, they should be taken on an empty stomach, as tolerated by the patient. Once-weekly dosing may give the same bone-density benefits as daily dosing because of these drugs’ extended duration of action.
CONCEPT REVIEW 36.2
* What are the major drug therapies used for the treatment of osteoporosis and related bone disorders?
[box]
Prototype Drug: *** Alendronate (Fosamax)
Therapeutic Class: Drug for osteoporosis Pharmacologic Class: Bone resorption inhibitor, bisphosphonate
Actions and Uses: Alendronate is approved for the following indications: prevention of osteoporosis in postmenopausal women, treatment of glucocorticoid-induced osteoporosis in both women and men, to increase bone mass in men with osteoporosis, and treatment of symptomatic Paget disease in both women and men. Alendronate is also used off-label for treating hypercalcemia due to malignancy. Therapeutic effects may take from 1 to 3 months to appear and may continue for several months after therapy is discontinued. All doses must be taken on an empty stomach, preferably in a fasting state 2 hours before breakfast.
Adverse Effects and Interactions: Common adverse effects of alendronate are diarrhea, nausea, vomiting, esophageal irritation, and a metallic or altered taste perception. Pathologic fractures may occur if the drug is taken longer than 3 months. Calcium supplements may decrease absorption of alendronate; therefore, use of these drugs together should be avoided. Food-drug interactions are common. Milk and other dairy products and medications, such as calcium, iron, antacids, and other mineral supplements, must be reviewed before beginning bisphosphonate therapy because they have the potential to decrease the effectiveness of bisphosphonates. Blood levels of the enzyme alkaline phosphatase are lowered with this drug.
Nursing Process Focus Patients Receiving Pharmacotherapy for Osteoporosis
ASSESSMENT
POTENTIAL NURSING DIAGNOSES*
Prior to administration:
* Obtain a complete health history, including musculoskeletal, GI, cardiovascular, neurologic, thyroid, parathyroid, renal, and liver conditions; allergies; drug history; and possible drug interactions.
* Evaluate laboratory blood findings: complete blood count (CBC), electrolytes, lipid panel, T3, T4 and TSH, and renal and liver function studies. Vitamin D levels may be obtained.
* Acquire the results of a complete physical examination, including vital signs, height, and weight.
* Collect a dietary history, noting adequacy of essential vitamins, minerals, and nutrients obtained through food sources.
* Obtain a history of current symptoms and effect on activities of daily living (ADLs).
* Deficient Knowledge related to a lack of information about drug therapy
* Infective Health Maintenance related to lifestyle changes or adverse drug effects
* Risk for Injury related to disease process and adverse drug effects
* Risk of Falls related to disease process and adverse drug effects
PLANNING: PATIENT GOALS AND EXPECTED OUTCOMES
The patient will:
* Experience therapeutic effects (a gain or maintenance of adequate bone density).
* Be free from or experience minimal adverse effects from drug therapy.
* Verbalize understanding of the drug’s use, adverse effects, and required precautions.
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IMPLEMENTATION
Interventions and (Rationales)
Patient Education/Discharge Planning
* Administer medication correctly, and evaluate the patient’s knowledge of proper administration. (Incorrect use may decrease absorption of medication.)
Instruct the patient:
* About the proper administration method guidelines.
* That bisphosphonates should be taken on an empty stomach, and to remain in a sitting position after taking medication.
* Review dietary history and discuss food source options, correcting any calcium and vitamin D deficiencies. (Adequate amounts of calcium, vitamin D, and magnesium are needed for bone health. If taking bisphosphonates, a review of foods and medications should be done because calcium-rich foods, medication, and supplements may decrease absorption of bisphosphonates.)
Inform the patient:
* To consume adequate amounts of calcium, vitamin D, and magnesium from food.
* That milk and other calcium-rich foods and medications (such as antacids and calcium supplements) must be reviewed before beginning bisphosphonate therapy.
* Monitor for adverse effects of medications. Bisphosphonates may cause GI irritation. SERMs increase the risk of venous thromboembolism and death from strokes. (Women with a history of thrombosis should not take this medication.)
Inform the patient that:
* Bisphosphonates may cause esophageal and gastric irritation, abdominal pain, and nausea; to report Immediately the onset of nausea or abdominal pain to the healthcare provider.
* SERMs may cause hot flashes, migraines, flu-like symptoms, endometrial problems, breast pain, and increase the risk of forming blood clots. Discontinue 3 days prior to surgery.
* Intranasal administration of calcitonin may cause nasal irritation and allergies.
* Review and monitor the use of other medications. (Concurrently using some medications with those used for osteoporosis may cause adverse effects or impact absorption.)
Instruct the patient:
* Not to take cholesterol-lowering drugs or estrogen replacement therapy concurrently with SERMs.
* If taking raloxifene along with warfarin, PT/INR should be tested when starting or stopping.
* Calcium supplements should not be used with bisphosphonates.
* Continue to monitor periodic laboratory tests, especially calcium, magnesium, phosphorus, and creatinine. Assess for signs or symptoms of hypo- or hypercalcemia. (These electrolytes should remain or return to normal limits. Increased creatinine levels may require discontinuation of medication.)
Instruct the patient to:
* Return periodically for laboratory tests.
* Report any symptoms of hypocalcemia (muscle spasms, facial grimacing, tingling sensations of hands or feet) or hypercalcemia (increased bone pain, anorexia, nausea, vomiting, constipation, thirst, lethargy, or fatigue) to the healthcare provider.
* Increase fluid intake, avoiding caffeine, soda, and alcohol. (Some kidney stones are composed of calcium; increasing fluid intake decreases the risk of kidney stone formation. Caffeine diminishes the absorption of calcium.)
Instruct the patient to:
* Increase fluid intake to 2 L/day.
* Avoid excessive caffeine because it diminishes the absorption of calcium.
* Limit or eliminate alcohol.
* Monitor for compliance with recommended lifestyle, for example, diet, exercise, and medication regimen. (Bone remodeling occurs over several months. The patient may discontinue the drug because of perceived lack of results.)
Inform the patient:
* To engage in weight-bearing exercises, three to five times a week.
* To acquire a minimum of 5-30 minutes of daily sun exposure for vitamin D synthesis.
* That the therapeutic effects of the medication(s) may take 1 to 3 months and to continue taking the drug as prescribed to ensure full effect.
EVALUATION OF OUTCOME CRITERIA
Evaluate the effectiveness of drug therapy by confirming that patient goals and expected outcomes have been met (see “Planning”). See Table 36.2 for a list of drugs to which these nursing actions apply.
***Herdman. T.H. & Kamitsuru, S. (Eds.), Nursing Diagnoses: Definitions & Classification 2015-2017. Copyright © 2014, 1994-2014 NANDA International. Used by arrangement by John Wiley & Sons, Inc. Companion website: www.wiley.com/go/nursingdiagnoses.
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osteo = bone
arthr = joint
itis = associated disease, often linked with inflammation
PAGET DISEASE Core Concept 36 5***
Treatment for Paget disease includes biologic therapies and bisphosphonates.
Paget disease, or osteitis deformans, is a chronic, progressive condition characterized by enlarged and abnormal bones. This condition is among the most common metabolic bone disorders. With this disorder, the processes of bone resorption and bone formation occur at a high rate. Excessive bone turnover causes the new bone to be weak and brittle, which may result in deformity and fractures. The patient may be asymptomatic or have only vague, nonspecific complaints for many years. Symptoms include pain of the hips and femurs, joint inflammation, headaches, facial pain, and hearing loss if bones around the ear cavity are affected. Nerves along the spinal column may be pinched in the compressed vertebrae.
Paget disease is sometimes confused with osteoporosis because some of the symptoms are similar. In fact, medical treatments for osteoporosis are similar to those for Paget disease. The cause of Paget disease, however, is quite different. Blood levels of the enzyme alkaline phosphatase are elevated because of the extensive bone turnover. Detection of this enzyme in the blood often provides early confirmation of the disease. Calcium blood levels are also increased. The symptoms of Paget disease can be treated successfully when diagnosis is made early. If the diagnosis is made late in the disease’s progression, permanent skeletal abnormalities may develop, and other disorders may appear, including arthritis, kidney stones, and heart disease.
Bisphosphonates are the preferred pharmacotherapy for Paget disease. Therapy is usually cyclic: Bisphosphonates are administered until serum alkaline phosphatase levels return to normal; then a drug-free period of several months follows. When serum alkaline phosphatase levels become elevated, therapy is begun again. The pharmacologic goals are to slow the rate of bone reabsorption and encourage the deposition of strong bone. Calcitonin nasal spray is used as an option for patients who cannot tolerate bisphosphonates. Surgery may be indicated in cases of severe bone deformity, degenerative arthritis, or fracture. Patients with Paget disease should receive adequate daily dietary intake of calcium and vitamin D. Sufficient exposure to sunlight is also important.
CONCEPT REVIEW 36.3
* Identify two important disorders characterized by weak and fragile bones. What are the major drug therapies used in their treatments?
OSTEOARTHRITIS Core Concept 36.6***
Analgesics and anti-inflammatory drugs are important components of pharmacotherapy for osteoarthritis.
Arthritis is a general term meaning inflammation of a joint. There are several types of arthritis, each having somewhat different characteristics based on the etiology. Because joint pain is common to both metabolic bone and joint disorders, analgesics and anti-inflammatory drugs are important components of pharmacotherapy. A few additional drugs are specific to the particular pathologies.
Osteoarthritis (OA) is a degenerative disease in which the cartilage at articular joint surfaces wears away. Like osteoporosis, this condition is considered to be an aging disorder. It is not accompanied by the degree of inflammation associated with other forms of arthritis. Signs are localized pain and stiffness, joint and bone enlargement, and limitations in movement. The cause of OA is thought to be excessive wear and tear of weight-bearing joints; the knee, spine, and hip are particularly affected.
The goals of pharmacotherapy for OA include reduction of pain and inflammation. The initial treatment of choice is acetaminophen. This drug should be used cautiously in geriatric patients and patients with chronic renal failure. For patients whose pain is unrelieved or untreatable by acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), including naproxen and ibuprofen, are usually given. Tramadol (Ultram) is a non-NSAID option for the treatment of moderate to severe pain. Although classified as an opioid, tramadol does not have abuse potential and is not a scheduled drug.
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CAM Therapy | Glucosamine and Chondroitin for Osteoarthritis
Glucosamine sulfate is a natural substance that is an important building block of cartilage. With aging, glucosamine is lost with the natural thinning of cartilage. As cartilage wears down, joints lose their normal cushioning ability, resulting in the pain and inflammation of OA. Glucosamine sulfate is available as an OTC dietary supplement. Some studies have shown it to be more effective than a placebo in reducing mild arthritis and joint pain. It is claimed to promote cartilage repair in the joints. Although reliable long-term studies are not available, glucosamine is marketed as a safe and inexpensive alternative to prescription anti-inflammatory drugs.
Chondroitin sulfate is another dietary supplement claimed to promote cartilage repair. It is a natural substance that forms part of the matrix between cartilage cells. Chondroitin is usually combined with glucosamine in specific arthritis formulas.
Opioids such as codeine may be combined with acetaminophen for severe pain.
Many patients with OA use over-the-counter (OTC) topical creams, gels, sprays, patches, or ointments that include salicylates (Aspercreme and Sportscreme), capsaicin (Capzasin), and counterirritants (Ben-Gay and Icy Hot). These therapies are well tolerated and produce few adverse effects. Pennsaid is a prescription, topical form of the NSAID diclofenac that is rubbed on the knee for symptoms of OA.
One approach to treating patients with moderate OA who do not respond adequately to analgesics is sodium hyaluronate (Hyalgan), a chemical normally found in high amounts within synovial fluid. Administered by injection directly into the knee joint, this drug replaces or supplements the body’s natural hyaluronic acid that deteriorated because of the inflammation of OA. By coating the articulating cartilage surface, Hyalgan helps provide a barrier that prevents friction and further inflammation of the joint.
RHEUMATOID ARTHRITIS *** Core Concept 36.7
Immunosuppressants and disease-modifying drugs are additional therapies used to treat rheumatoid arthritis.
Rheumatoid arthritis (RA) is a systemic autoimmune disorder that causes disfigurement and inflammation of multiple joints that usually occurs at an earlier age than OA. RA is the second most common form of arthritis and has an autoimmune etiology. In RA, autoantibodies, called rheumatoid factors, activate other inflammatory substances called complement proteins and draw leukocytes into an area where they attack normal cells. This results in ongoing injury and formation of inflammatory fluid within the joints. Joint capsules, tendons, ligaments, and skeletal muscles may also be affected. Unlike OA, which causes local pain in affected joints, patients with RA may develop systemic manifestations that include infections, pulmonary disease, pericarditis, abnormal numbers of blood cells, and symptoms of metabolic dysfunction such as fatigue, anorexia, and weakness.
The goals for the pharmacotherapy of RA include management of pain and inflammation and slowing the progress of the disease. The same classes of analgesics and anti-inflammatory drugs used to treat OA are used to manage RA. If inflammation is especially severe, short-term therapy with corticosteroids may be indicated (see Chapter 33).
Additional drugs are sometimes prescribed to manage the immune aspects of RA. Research has shown that the progression of tissue damage can be slowed by the use of disease-modifying antirheumatic drugs (DMARDs). DMARDs may require several months of treatment before maximum therapeutic effects are achieved. Because many of these drugs can be toxic, patients should be closely monitored. Adverse effects vary depending on the type of drug. There are many DMARDs available, and these drugs are listed in Table 36.3.
Pharmacotherapy for RA occurs in a stepwise manner. Patients who have mild to moderate disease start on monotherapy with a nonbiologic DMARD, usually hydroxychloroquine (Plaquenil), methotrexate (Rheumatrex, Trexall), leflunomide (Arava), or sulfasalazine (Azulfidine). If symptoms have not improved or have worsened after 3 months of monotherapy, a second DMARD is added to the regimen.
[sidebar]
rheuma = watery discharge
toid = associated
auto = self-directed
anti = against
bodies = things
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cyto = cell
kine = mediator
Table 36.3 Disease-Modifying Antirheumatic Drugs (DMARDs)
Drug
Route and Adult Dose
Remarks
NONBIOLOGIC THERAPIES
azathioprine (Azasan, Imuran)
PO: 1-2.5 mg/kg/day once or in divided doses bid
Immunosuppressant and anti-inflammatory; may cause bone marrow depression
***hydroxychloroquine (Plaquenil)
PO: 400-600 mg/day
Also used for acute malaria and malaria suppression
leflunomide (Arava)
PO: loading dose: 100 mg/day for 3 days then 10-20 mg daily
Immunomodulator with anti-inflammatory effects; may cause Stevens-Johnson syndrome
methotrexate (Rheumatrex, Trexall) (see the Prototype Drug box in Core Concept 29.8)
PO: 7.5 mg once/wk or 2.5-5 mg every
12 hours for three doses each week (max 20 mg/week)
Folic acid blocker; antineoplastic and immunosuppressant; may cause liver toxicity, sudden death, and pulmonary fibrosis
sulfasalazine (Azulfidine)
PO: 1-2 g daily in divided doses (max: 8 g/day)
Also for ulcerative colitis
BIOLOGIC THERAPIES (BIOLOGIC RESPONSE MODIFIERS)
abatacept (Orencia)
IV: 500-1000 mg given on 0, 2, and 4 weeks, then every 4 weeks thereafter
Immune modulating drug; inhibits T lymphocyte activation
adalimumab (Humira)
Subcutaneous: 40 mg every other week
Tumor necrosis factor blocker
anakinra (Kineret)
Subcutaneous: 100 mg per day
lnterleukin-1 receptor blocker
certolizumab pegol (Cimzia)
Subcutaneous: 400 mg initially and at weeks 2 and 4, followed by 200 mg every other week
Tumor necrosis factor blocker
etanercept (Enbrel)
Subcutaneous: 25 mg twice weekly; or 0.08 mg/kg or 50 mg once weekly
Tumor necrosis factor blocker
golimumab (Simponi)
Subcutaneous: 50 mg once monthly
Injectable man-made protein that binds to tumor necrosis factor and blocks its action
infliximab (Remicade)
IV: 3 mg/kg followed by 3 mg/kg 2 weeks and 6 weeks after initial dose and then every 8 weeks
Tumor necrosis factor-alpha blocker used in combination with methotrexate
rituximab (Rituxan)
IV: 1000 mg every 2 weeks for a total of two doses (give a corticosteroid 30 minutes prior to treatment)
Also indicated for the treatment of non-Hodgkin lymphoma
tocilizumab (Actemra)
IV: 4-8 mg/kg every other week
lnterleukin-6 receptor blocker
tofacitinib (Xeljanz)
PO: 5 mg bid
Inhibits an enzyme called janus kinase (JAK), which drives the inflammatory process in RA
A third DMARD may be added for patients with persistent disease.
Patients with severe RA or who have not responded to nonbiologic therapies may receive biologic therapies also called biologic response modifiers. These biologic agents, most of which are monoclonal antibodies, block steps in the inflammatory cascade, reduce joint inflammation, and slow the progression of joint damage. Adalimumab (Humira), etanercept (Enbrel), certolizumab (Cimzia), golimumab (Simponi), and infliximab (Remicade) are tumor necrosis factor (TNF) blockers. TNF is a naturally occurring cytokine produced by macrophages and activated T cells that mediates inflammation and modulates cellular immune responses. Combinations of biologic and nonbiologic agents may be necessary for some patients.
[box]
Prototype Drug: *** Hydroxychloroquine (Plaquenil)
Therapeutic Class: Disease-modifying antirheumatic drug (DMARD), rheumatoid drug Pharmacologic Class: Protein synthesis inhibitor, inhibitor of DNA and RNA polymerase
Actions and Uses: Hydroxychloroquine is prescribed for RA and lupus erythematosus in patients who have not responded well to other anti-inflammatory drugs. This drug relieves the severe inflammation characteristic of these disorders. For full effectiveness, hydroxychloroquine is most often prescribed with salicylates and glucocorticoids. This drug has also been used for prophylaxis and treatment of malaria.
Adverse Effects and Interactions: Adverse symptoms include GI disturbances, loss of hair, headache, and mood and mental changes. Hydroxychloroquine has possible ocular effects that include blurred vision, photophobia, diminished ability to read, and blacked out areas in the visual field.
Antacids with aluminum and magnesium may prevent absorption. This drug Interferes with the patient’s response to the rabies vaccine. Hydroxychloroquine may increase the risk of liver toxicity when administered with drugs that are toxic to the liver. It also may lead to increased digoxin levels. Alcohol use should be eliminated during therapy because it may increase the risk of liver toxicity.
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Fast Facts Arthritis and Joint Disorders
* Between 20 million and 40 million patients in the United States are affected by OA.
* After age 40, more than 90% of the population has symptoms of OA in major weight-bearing joints. After 70 years of age, almost all patients have symptoms of OA.
* Of the world’s population, 1% has RA, which most often affects patients between 30 and 50 years of age. Women are three to five times more likely to develop RA than men.
* Between 1% and 3% of the U.S. population is affected by gout. Most of the patients are men between the ages of 30 and 60. Women are more likely to be affected after menopause.
CONCEPT REVIEW 36.4
* Identify the major types of arthritis. What are the general differences between these disorders?
GOUT *** Core Concept 36.8
Pharmacotherapy for gout requires drugs that control uric acid levels.
Gout, a form of acute arthritis, is a metabolic disorder caused by the accumulation of uric acid in the bloodstream or joint cavities. This disorder is extremely painful. Gout occurs when excretion of uric acid by the kidneys is reduced. One metabolic step important to the pharmacotherapy of this disease is the conversion of hypoxanthine (part of the chemical structure of the genes found with the body’s cells) to uric acid by the enzyme xanthine oxidase. An elevated blood level of uric acid is called hyperuricemia.
Gout may be classified as primary or secondary. Primary gout, caused by genetic errors in uric acid metabolism, is most commonly observed in Pacific Islanders. Secondary gout is caused by diseases or drugs that increase the metabolic turnover of nucleic acids or that interfere with uric acid excretion. Examples of drugs that may cause gout include thiazide diuretics, aspirin, cyclosporine, and alcohol (when ingested on a chronic basis). Conditions that can cause secondary gout include diabetic ketoacidosis, kidney failure, and diseases associated with a rapid cell turnover, such as leukemia, hemolytic anemia, and polycythemia.
Acute gouty arthritis occurs when needle-shaped uric acid crystals accumulate in joints, resulting in red, swollen, and inflamed tissue. Attacks have a sudden onset; often occur at night; and may be triggered by diet, injury, or other stresses. Gouty arthritis most often occurs in the big toes, heels, ankles, wrists, fingers, knees, and elbows. About 90% of patients with gout are men.
NSAIDs are the preferred drugs for treating the pain and inflammation associated with acute gout attacks. Indomethacin (Indocin) and naproxen (Naprosyn) are NSAIDs that have been widely used for acute gout. Corticosteroids may be used to treat exacerbations of acute gout, particularly when the symptoms are in a single joint, and the medication can be delivered intra-articularly.
Uric acid-inhibiting drugs treat the gouty condition (Table 36.4). The use of colchicine (Colcrys) has declined, although it may still be prescribed for patients whose symptoms cannot be controlled with NSAIDs. Low doses may be prescribed for gout prophylaxis.
Most patients with acute gouty arthritis will experience subsequent attacks within 1 to 2 years after the first attack. Thus, long-term prophylactic therapy with drugs that lower serum uric acid is often initiated. This can be accomplished through three strategies.
One strategy to prevent hyperuricemia is to use uricosurics, drugs that increase the excretion of uric acid by blocking its reabsorption in the kidney. The uricosuric drugs used for gout prophylaxis include probenecid (Probalan) and sulfinpyrazone (Anturane).
A second strategy for preventing hyperuricemia is to reduce the formation of uric acid. The traditional drug for gout prophylaxis, allopurinol (Lopurin, Zyloprim), blocks the enzyme xanthine oxidase, thus reducing the formation of uric acid. A newer antigout drug, febuxostat (Uloric), acts by the same mechanism as allopurinol but is safer for patients with renal impairment because it is not excreted by the kidneys.
[sidebar]
hyper = elevated
uric = uric acid
emia = blood level
uricos = uric acid excretion
urics = impact on urination
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Table 36.4 Drugs for Gout and Gouty Arthritis
Drug
Route and Adult Dose
Remarks
***allopurinol (Lopurin, Zyloprim)
PO (primary): 100 mg daily (max: 800 mg/day) PO (secondary): 200-800 mg dally
For both primary and secondary hyperuricemia and prevention of gout flare-up
colchicine (Colcrys)
PO: 0.5-1.2 mg followed by 0.5-0.6 mg every 1-2 hours until pain relief (max: 1.2 mg/day)
For acute gouty attack; may cause gastric upset at higher doses; IV form available
febuxostat (Uloric)
PO: 40-80 mg once daily
For management of chronic hyperuricemia in patients with gout
pegloticase (Krystexxa)
IV: 8 mg every 2 weeks
For chronic gout; enzyme that metabolizes uric acid
probenecid (Benemid, Probalan)
PO: 250 mg bid for 1 week; then 500 mg bid (max: 3 g/day)
For gout; also used as an adjunctive drug for penicillin or cephalosporin therapy
rasburicase (Elitek)
IV: 0.2 mg/kg over 30 minutes for up to 5 days
For management of plasma uric acid levels in pediatric patients with leukemia; recombinant urate-oxidase produced by a genetically modified Saccharomyces cerevisiae (yeast) strain; may cause hypersensitivity reactions
sulfinpyrazone (Anturane)
PO: 100-400 mg bid
For gout; also used for inhibition of platelet aggregation
A third strategy for preventing hyperuricemia is to convert uric acid to a less toxic form. Two drugs are available that act by this mechanism. Rasburicase (Elitek) is an enzyme produced through recombinant DNA technology that is used to reduce uric acid levels in patients who are receiving cancer chemotherapy. Approved in 2010, pegloticase (Krystexxa) is a synthetic enzyme that metabolizes uric acid to an inert substance. It is used to lower uric acid levels in patients with chronic gout who have not responded to conventional therapies.
CONCEPT REVIEW 36.5
* Identify drug therapies used to treat the major arthritic and joint disorders.
[box]
Prototype Drug: *** Allopurinol (Lopurin, Zyloprim)
Therapeutic Class: Antigout drug Pharmacologic Class: Inhibitor of uric acid formation, xanthine oxidase blocker
Actions and Uses: Allopurinol reduces the production of uric acid, controlling the buildup of uric acid that causes severe gout. Therefore, it reduces the risk of acute gout attacks. It is also approved to prevent recurrent kidney stones in patients with elevated uric acid levels. It may be used prophylactically to reduce the severity of the elevated uric acid blood levels associated with antineoplastic and radiation therapies, both of which increase blood uric acid levels by promoting nucleic acid degradation. This drug takes 1 to 3 weeks to bring blood uric acid levels to within the normal range.
Adverse Effects and Interactions: The most frequent and serious adverse effects are skin rash and rare cases of fatal toxic epidermal necrolysis and Stevens-Johnson syndrome.
Other possible adverse effects include drowsiness, headache, vertigo, nausea, vomiting, abdominal discomfort, malaise, diarrhea, retinopathy, and thrombocytopenia.
Alcohol may inhibit the renal excretion of uric acid. Ampi-cillin and amoxicillin may increase the risk of skin rashes. An enhanced anticoagulant effect may be seen with the use of warfarin. The risk of ototoxicity is increased when allopurinol is used with thiazides and anglotensin-converting enzyme (ACE) inhibitors. Aluminum antacids taken concurrently with allopurinol may decrease its effects. An increased effect may be seen with phenytoin and anticancer drugs, necessitating the need for altered doses of these medications.
[box]
Patients Need to Know
Patients taking drugs for bone or joint disorders need to know the following:
In General
1. When receiving treatment for problems with mobility, it often takes several weeks for effectiveness to begin. Follow the advice of a healthcare provider in order to achieve full therapeutic effect.
Regarding Calcium and Bone-Regulating Medications
2. When taking calcium or vitamin D supplements, be aware of the signs and symptoms of hypercalcemia. Check with the healthcare provider or pharmacist before taking supplements of any kind. In some cases, only proper diet and sunshine are needed for successful therapy.
3. Calcium may react with some foods or interfere with the absorption of iron and bisphosphonates.
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4. Be familiar with the risks and long-term effects of vitamin D therapy, corticosteroids, hormone therapy involving estrogen, and estrogen-receptor modulators. Major undesirable adverse effects could occur in some cases.
5. Know how to use a nasal spray if taking calcitonin by this method.
6. Be aware that some vitamins may interfere with the pharmacologic effects of calcitonin.
7. Some medications cause GI discomfort. Most drugs like these can be taken after meals or with milk to minimize discomfort.
Regarding Arthritic and Joint-Related Medications
8. Report any unfavorable symptoms such as bone pain, restricted mobility, inflammation, or fracture to a healthcare provider. Report any muscle pain because muscles that have not been moved for a while may feel stiff and tender.
9. When taking some antigout medications, drink plenty of fluids to avoid kidney stones. To ensure proper fluid balance, monitor intake and output of fluids.
10. When taking probenecid, avoid taking aspirin because it interferes with the drug’s action. Take acetaminophen instead.
[box]
Safety Alert: Soundalike Drug Names
Nurses need to counsel patients about ways to avoid a self-medication error when taking medications that are “soundalike” drugs, such as Celebrex and Celexa. Confusing drugs with similar names accounts for about approximately 10% of all medication errors, according to the U.S. Food and Drug Administration
(FDA). Patients could ask the pharmacist to package the “soundalikes” in distinctly different containers or to label the bottles with large letters describing the drug’s use, like PAIN PILL and ANTIDEPRESSANT.
Chapter Review Core Concepts Summary
36.1 Adequate levels of calcium, vitamin D, parathyroid hormone, and calcitonin are necessary for bone and body homeostasis.
One of the most important minerals in the body responsible for proper nerve conduction, muscle contractions, and bone formation is calcium. Calcium homeostasis is controlled by two important hormones, PTH and calcitonin. These hormones influence major body targets: the bones, kidneys, and GI tract. They direct the processes of bone resorption and bone deposition. Active vitamin D increases calcium absorption from the GI tract and helps to keep proper calcium balance in the body.
36.2 Hypocalcemia is a serious condition that requires immediate therapy.
Hypocalcemia, or lowered calcium levels in the bloodstream, is a sign of an underlying disorder; therefore, identifying its cause is essential. Signs of hypocalcemia are nerve and muscle excitability, muscle twitching, tremor, or cramping. These conditions are often reversed with calcium salts. Calcium salts consist of complexed and elemental calcium. Elemental calcium is also obtained from dietary sources.
36.3 Osteomalacia and rickets are successfully treated with calcium salts and vitamin D supplements.
Osteomalacia, called rickets in children, is a disorder characterized by softening of bones without alteration of basic bone structure. Drug therapy for children and adults consists of calcium and vitamin D supplements.
36.4 Treatment for osteoporosis includes calcitonin, selective estrogen-receptor modulators, and bisphosphonates.
Osteoporosis, or weak bones caused by disrupted bone homeostasis, is the most common metabolic bone disease. The onset of menopause is the most frequent risk factor. Many drug therapies are available for this disorder, including calcium and vitamin D supplements, calcitonin, SERMs, and bisphosphonates.
36.5 Treatment for Paget disease includes biologic therapies and bisphosphonates.
Paget disease is a chronic progressive condition characterized by enlarged and abnormal bones. Although the cause of Paget disease is different from that of osteoporosis, medical treatments are similar. Bisphosphonates are drugs primarily used in the pharmacotherapy of this disorder.
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36.6 Analgesics and anti-inflammatory drugs are important components of pharmacotherapy for osteoarthritis.
The initial pharmacotherapy goals for OA are to reduce pain and inflammation. Acetaminophen and NSAIDs may be taken. Tramadol and opioids may be combined with acetaminophen for severe pain. OTC topical creams, gels, sprays, patches, or ointments may be used. For patients with moderate OA who do not respond to analgesics, sodium hyaluronate may be applied.
36.7 Immunosuppressants and disease-modifying drugs are additional therapies used to treat rheumatoid arthritis.
RA is the second most common form of arthritis and has an autoimmune etiology. Pharmacotherapy for RA includes the same classes of analgesics and anti-inflammatory drugs, plus DMARDs and immunosuppressants.
36.8 Pharmacotherapy for gout requires drugs that control uric acid levels.
Gout is caused by an accumulation of uric acid in the bloodstream. Gout may be classified as a primary or secondary condition. Acute gouty arthritis occurs when needle-shaped uric acid crystals accumulate in the joints. The goals of gout pharmacotherapy include termination of acute attacks and prevention of future attacks with several approaches to control uric acid levels.
REVIEW Questions
Answer the following questions to assess your knowledge of the chapter material, and go back and review any material that is not clear to you.
1. There are many trade names for certain medications. The trade name of a medication that lowers serum alkaline phosphatase is:
1. Azulfidine.
2. Fosamax.
3. Colchicine.
4. Benemid.
2. The patient on raloxifene (Evista) has had warfarin (Coumadin) ordered. The nurse incorporates what laboratory test into the plan of care?
1. Platelets
2. White blood count
3. Sodium
4. Prothrombin time and international normalized ratio (PT/INR)
3. The patient taking calcitriol should be monitored for:
1. Dysrhythmias.
2. Hypercalcemia.
3. Fluid overload.
4. Flu-like symptoms.
4. For the patient diagnosed with gout, the nurse would most likely administer which medication?
1. Calcitriol (Calcijex, Rocaltrol)
2. Azathioprine (Imuran)
3. Allopurinol (Lopurin, Zyloprim)
4. Raloxifene (Evista)
5. Because esophageal irritation can occur, the nurse instructs the patient to remain in an upright position for 30 minutes after taking which medication?
1. Allopurinol (Lopurin)
2. Calcitonin
3. Alendronate (Fosamax)
4. Raloxifene (Evista)
6. A patient is about to begin taking calcitonin and asks if this drug has any adverse effects. The healthcare provider tells the patient that it may cause:
1. Nasal irritation.
2. Headaches.
3. Watery eyes.
4. Sinus infection.
7. A patient has been taking hydroxychloroquine (Plaquenil) for rheumatoid arthritis. Which of the following symptoms may be an adverse effect?
1. Cardiac dysrhythmias
2. Joint stiffness
3. Blurred vision
4. Decreased muscle strength
8. The nurse is speaking at the local community center about vitamin and mineral supplements. She tells the audience that a milliequivalent (mEq) is the unit used to describe the amount of electrolyte available to the bloodstream; the higher the mEq, the more potent the calcium salt. To demonstrate their new knowledge, the nurse has the group choose the calcium salts with the greatest potency. Which do they choose?
1. Calcium chloride
2. Calcium citrate
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3. Calcium phosphate
4. Calcium gluconate
9. The nurse would include calcitonin in the plan of care for patients with: (Select all that apply.)
1. Paget disease.
2. Hypercalcemia.
3. Hypocalcemia.
4. Osteoporosis.
5. Osteoarthritis.
10. The healthcare provider has ordered tocilizumab (Actemra), 5 mg/kg, to be given IV. The patient weighs 121 pounds and is to receive 275 mg in a 250 mL bag of solution to be delivered over 4 hours. How many milliliters will the patient receive in 1 hour?
1. 60 mL
2. 62 mL
3. 61.5 mL
4. 62.5 mL
CASE STUDY Questions
[Image: Mr. Steven Hurtt.]
Remember Mr. Hurtt, the patient introduced at the beginning of the chapter? Now read the remainder of the case study. Based on the information you have learned in this chapter, answer the questions that follow.
Mr. Steven Hurtt is a 67-year-old white male. In an office visit, Mr. Hurtt complains of joint pain in the knees, ankles, toes, and shoulders. Over the last several years, he has taken aspirin for overall pain. Laboratory tests and physical examination yield the following information: small nodules found sporadically under the skin, acute swelling of the knees, redness of the big toe, and elevated uric acid and white blood cell (WBC) count in the blood. Mr. Hurtt is diagnosed with gouty arthritis and is prescribed allopurinol (Lopurin).
1. Mr. Hurtt asks how allopurinol works. The nurse explains that it works by:
1. Decreasing the deposits of uric acid in the joint spaces.
2. Reducing the pain associated with joint inflammation by uric acid crystals.
3. Increasing renal excretion of uric acid.
4 Reducing the production of uric acid.
2. Since Mr. Hurtt is starting on allopurinol, the nurse informs him that this medication has several possible adverse effects that he needs to know about. These effects include: (Select all that apply.)
1. Headache.
2. Vertigo.
3. Toxic epidermal necrolysis.
4. Skin rash.
3. Mr. Hurtt asks why he should avoid drinking alcohol while he is taking allopurinol. The nurse responds by telling him that alcohol:
1. Significantly increases the drug levels of allopurinol.
2. Interferes with the absorption of antigout medications.
3. Raises uric acid levels.
4. Causes the urine to become more alkaline.
4. Which of the following statements demonstrates that Mr. Hurtt needs additional instruction?
1. “I will take my allopurinol as prescribed by my healthcare provider.”
2. “I will stop having alcoholic beverages.”
3. “I will avoid high purine foods.”
4. “I will continue taking my aspirin.”
Answers and complete rationales for the Review and Case Study Questions appear in Appendix A.
REFERENCE
Herdman, T. H„ & Kamitsuru, S. (Eds.). (2014). NANDA International nursing diagnoses: Definitions and classification, 2015-2017. Oxford, United Kingdom: Wiley-Blackwell.
SELECTED BIBLIOGRAPHY
Bethel, M. (2015). Osteoporosis. Retrieved from http://emedicine.
medscape.com/article/330598-overview Buch, M. H., & Emery, P. (2011). New therapies in the management of rheumatoid arthritis. Current Opinion in Rheumatology, 23, 245-251.
doi:10.1097/BOR.0b013e3283454124
Centers for Disease Control and Prevention. (2015). Gout. Retrieved from http://www.cdc.gov/arthritis/basics/gout.html
Centers for Disease Control and Prevention. (2015). Rheumatoid arthritis. Retrieved from http://www.cdc.gov/arthritis/basics/rheu-matoid.htm
Centers for Disease Control and Prevention. (2016). Arthritis facts. Retrieved from http://www.cdc.gov/arthritis/press/factsheet. htm
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Centers for Disease Control and Prevention. (2016). Arthritis-related statistics. Retrieved from http://www.cdc.gov/arthritis/data_sta-tistics/arthritis-related-stats.htm
Duque, G. (2013). Osteoporosis in older persons: Current pharmacotherapy and future directions. Expert Opinion on Pharmacotherapy, 24, 1949-1958. doi:10.1517/14656566.2013.822861
Gennari, L., Merlotti, D., Rendina, D., Gianfrancesco, E, Esposito, T., & Nuti, R. (2014). Paget’s disease of bone: Epidemiology, pathogenesis and pharmacotherapy. Expert Opinion on Orphan Drugs, 2, 591-603. doi:10.1517/21678707.2014.904225
Islam, M. J., Yusuf, M. A., Hossain, M. S., & Ahmed, M. (2013). Updated management of osteoarthritis: A review, journal of Science Foundation, 11,49-55. doi:10.3329/jsf.vlli2.21597
Lawrence, R. C, Felson, D. T., Helmick, C. G., Arnold, L. M., Choi, H., Deyo, R. A., … National Arthritis Data Workgroup. (2012). Estimates of the prevalence of arthritis and other rheumatic conditions in the United States, Part II. Arthritis and Rheumatism, 58, 26-35. doi:10.1002/art.23176
Mayo Clinic, (n.d.). Rheumatoid arthritis treatment. Retrieved from http://www.mayoclinic.org/diseasesconditions/rheumatoidarthritis/diagnosistreatment/treatment/txc-20197400
National Institute of Arthritis and Musculoskeletal and Skin Diseases. (2016). Handout on health: Rheumatoid arthritis. Retrieved from http://www.niams.nih.gov/Health_Info/Rheumatic_Disease
National Osteoporosis Foundation, (n.d.). Bone health basics: Get the facts. Retrieved from https://www.nof.org/prevention/ general-facts
Owens, G. M. (2015). Optimizing Rheumatoid Arthritis Therapy: Using Objective Measures of Disease Activity to Guide Treatment. American Health and Drug Benefits, 8, 354-360.
World Health Organization, (n.d.). Chronic rheumatic conditions. Retrieved from http://www.who.int/chp/topics/rheumatic/en
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Chapter 37 Drugs for Skin Disorders
[Image: Burt Nicholson.]
“I don’t think I can go to the game this weekend. Can anything he done to get rid of these zits by Friday?”
Burt Nicholson
Core Concepts
37.1 Layers of skin provide protection to the body.
37.2 The major causes of skin disorders are injury, aging, inherited factors, and other medical conditions.
37.3 Scabicides and pediculicides treat parasitic mite and lice infestations.
37.4 The goal of drug therapy for sunburn is to eliminate discomfort until healing occurs.
37.5 Acne and rosacea are treated by a combination of over-the-counter and prescription drugs.
37.6 Topical corticosteroids are used mainly to treat dermatitis and related symptoms.
37.7 Several topical and systemic medications are used to treat psoriatic symptoms.
Drug Snapshot
The following drugs are discussed in this chapter:
Drug Classes
Prototype Drugs
DRUGS FOR SKIN PARASITES
Scabicides and pediculicides
*** permethrin (Acticin, Elimite, Nix)
DRUGS FOR SUNBURN AND MINOR SKIN IRRITATION
Topical anesthetics
*** benzocaine (Américaine, Anbesol, others)
DRUGS FOR ACNE AND ROSACEA
Topical medications
***tretinoin (Avita, Retin-A, Tretin-X)
DRUGS FOR DERMATITIS AND ECZEMA
DRUGS FOR PSORIASIS
Learning Outcomes
After reading this chapter, the student should be able to:
1. Identify important skin layers, and explain how superficial skin cells must be replaced after they become damaged or lost.
2. Describe major symptoms associated with stress and injury to the skin versus those associated with a patient’s changing age or health.
3. Describe popular treatments used in conjunction with available drug therapies to treat skin disorders, and identify the major actions, primary actions, and important adverse effects of the following types of drugs: scabicides, pediculicides, topical anesthetics, and topical medications, as well as antibiotics, retinoids, keratolytic agents, corticosteroids, emollients, and psoralens.
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Key Terms
closed comedones (KOME-eh-dones)
dermatitis (dur-mah-TIE-tiss)
eczema (ECK-zih-mah)
emollients
erythema (ear-ih-THEE-mah)
keratinization (keh-RAT-en-eye zay-shun)
keratolytic agents (keh-RAT-oh-lih-tik)
open comedones
papules (PAP-yools)
pediculicides (puh-DIK-you-lih-sides)
pruritus (proo-RYE-tus)
psoralens (SOR-uh-lenz)
psoriasis
pustules (PUSS-chools)
retinoids (RETT-ih-noydz)
retinol (RETT-in-nall)
rosacea (roh-ZAY-shee-uh)
scabicides (SKAY-bih-sides)
scabies (SKAY-beez)
seborrhea (seb-oh-REE-ah)
urticaria (EHR-tik-air-ee-ah)
The integumentary system consists of the skin, hair, nails, sweat glands, and oil glands. The organ in the body with the largest surface area is the skin. It is considered a window to the body’s health. The skin provides an effective barrier between extreme conditions of the outside environment and the body’s internal tissues. At times, changes in external or internal conditions can damage the skin. When this happens, drug therapy can improve the skin’s condition. The relationship between the integumentary system and other systems in the body is shown in Figure 37.1.
Endocrine system
Hormones influence glandular activity, calcium homeostasis, and skin health.
Muscular system
The skin and muscles are important for proper body movement and expression.
Lymphatic system
Helps fight diseases and Infections of the skin.
Digestive system
Proper nutrition is important for healthy skin.
The integumentary system
Nervous system
Emotions affect skin coloration. The skin is a sensory organ.
Respiratory system
The lungs provide oxygen to all cells in the body.
Skeletal system
The bones are a storage site for calcium, an important mineral connected with vitamin D function.
For all systems
The skin forms a protective barrier against hazardous conditions.
Reproductive system
The skin covers external genitalia. Sex hormones influence skin health.
FIGURE 37.1 The Integumentary system (skin) and how the other body systems affect it.
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The purpose of this chapter is to examine the broad scope of skin disorders and the medications used for skin therapy. Particular attention is given to drugs that are of direct benefit to lice and mite infestations, sunburn, acne, inflammation, and dry, scaly skin.
*** Core Concept 37.1 Layers of skin provide protection to the body.
The integument has two major layers: the epidermis and the dermis. It also has a subcutaneous layer called the hypodermis. Each layer of the integument is distinct in form and function and determines how drugs are injected or applied to the surface of the skin (see Chapter 3).
The most superficial skin layer is the epidermis. Depending on its thickness, the epidermis has either four or five sublayers. The strongest and outermost sublayer is the stratum corneum, or horny layer. It is called this because of the abundance of the protein keratin, also found in the hair, hooves, and horns of many vertebrate mammals. Not every part of the skin has a large amount of keratin –only those areas that are subject to mechanical stress –for example, the soles of the feet and the palms of the hands.
The deepest sublayer of the epidermis is the stratum basale, also called the stratum germinativum. It supplies the epidermis with new cells after older superficial cells have been damaged or lost by normal wear. Cells must migrate over their lifetime to the outermost layers of the skin, where they eventually fall off. As these cells are pushed to the surface, they are flattened and covered with a water-insoluble material, forming a protective seal. The average time it takes for a cell to move from the basale layer to the outer body surface is about 3 weeks. Specialized cells called melanocytes within the deeper layers of the epidermis secrete the dark pigment melanin, which offers a degree of protection from the sun’s ultraviolet rays.
The next major layer of skin, the dermis, is made up of dense, irregular connective tissue, which has an irregular arrangement of thick collagen fibers. The dermis provides a foundation for the epidermis and appendages such as hair and nails. Most receptor nerve endings, sweat glands, oil glands, and blood vessels are found within the dermis.
Below the dermis, the subcutaneous layer composed mainly of adipose tissue or fat cushions, insulates, and provides a source of energy for the body. The hypodermis is involved with maintaining homeostasis, regulating body temperature, and storing energy in the form of lipids.
*** Core Concept 37.2
The major causes of skin disorders are injury, aging, inherited factors, and other medical conditions.
Skin that is dry, cracked, scaly, or inflamed represents a disturbance in the outermost skin layer. Pruritus, or itching, is a general symptom often associated with dry, scaly skin, or it may be a symptom of infestation with mites and lice. Urticaria, commonly referred to as hives, is recognized as raised, red, itchy bumps. Most commonly, urticaria is caused by an allergic reaction. Many drugs, especially antibiotics, can cause urticaria and pruritus as side effects. Although most drug allergies of the skin require only symptomatic treatment with over-the-counter (OTC) medications, some are severe. Toxic epidermal necrolysis (TEN) is a life-threatening drug reaction that results in massive death of skin cells and separation of the epidermis from the dermis.
Burns are a unique type of stress that may affect all layers of the skin. They are classified according to the degree of skin damage. First-degree burns affect only the outer layers of the epidermis, are characterized by redness, and are analogous to sunburn. Second-degree burns affect most of the epidermis and part of the dermis, resulting in inflammation and blisters. Third-degree burns are full-thickness burns; all layers of the skin are damaged. With full-thickness burns, the skin cannot regenerate, and skin grafting is required.
Inflammation, a characteristic of burns and other traumatic disorders, occurs when damage to the skin is extensive. Signs accompanying inflammation include erythema or redness, irritation, and pain. Symptoms including bleeding, bruises, and infections may accompany trauma to deeper tissues.
Not all skin disorders are associated with injury or infection. Many common skin disorders are related to inherited factors or the normal aging process. Sometimes the skin may appear unhealthy because of a disease process occurring in a different organ system, such as yellowing of the skin (jaundice) that occurs from liver damage.
[sidebar]
prur = itching
itus = condition
eryth = red
ema = appears
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In many cases, the cause of the skin condition may be unknown. Common symptoms associated with a range of conditions are presented in Table 37.1. Although the causes and symptoms of skin conditions are very diverse, a simple method of classifying them is shown in Table 37.2.
Most skin conditions are not debilitating and require only intermittent drug therapy. A few irritating disorders are of particular importance to patients who require treatment on an outpatient basis. Examples include lice infestation, minor sunburn, and acne. Eczema, dermatitis, and psoriasis are more serious disorders requiring therapy for a longer time. Figure 37.2 shows examples of regions of the body where irritating symptoms most likely appear.
CONCEPT REVIEW 37.1
* Identify the skin layers protecting the body. Give examples of layers specifically affected by minor or major external stresses. What skin disorders are not related to the external environment? How would you categorize most skin disorders?
Table 37.1 Signs and Symptoms of Skin Conditions Associated with a Patient’s Changing
Health, Age, or Weakened Immune System
Delicate skin, wrinkles, and hair loss
Many degenerative changes occur in the skin; some are found in older patients; others are genetically related (fragile epidermis, wrinkles, reduced activity of oil and sweat glands, male pattern baldness, poor blood circulation); hair loss may also be linked to some medical procedures, such as radiation and chemotherapy.
Discoloration of the skin
Discoloration is often a sign of another medical disorder (for example, anemia, cyanosis, fever, jaundice, or Addison disease); some medications have photosensitive properties, making a patient’s skin sensitive to the sun and causing erythema.
Scales, patches, and itchy areas
Some symptoms may be related to a combination of genetics, stress, and immunity; other symptoms may be related to a fast turnover of skin cells; some symptoms develop for unknown reasons.
Seborrhea, oily skin and bumps
Conditions are usually associated with a younger age group; examples include cradle cap in infants and an oily face, chest, arms, and back in teenagers and young adults; pustules, cysts, papules, and nodules represent lesions connected with oily skin.
Tumors
Tumors may be genetic or may occur because of exposure to harmful agents or conditions.
Warts, skin marks, and moles
Some skin marks are congenital; others are acquired or may be linked to environmental factors.
Table 37.2 Classification of Skin Disorders
Infectious disorders
Bacterial infections: boils, impetigo, and infected hair follicles
Fungal infections: ringworm, athlete’s foot, jock itch, and nail infections
Parasitic infections: ticks, mites, and lice
Viral infections: cold sores, fever blisters (herpes simplex), chickenpox, warts, shingles (herpes zoster), measles (rubeola), and German measles (rubella)
Inflammatory disorders
Injury and exposure to the sun
Combination of overactive glands, increased hormone production, or infection such as acne and rosacea
Disorders marked by Itching, cracking, and discomfort, such as atopic dermatitis, contact dermatitis, seborrheic dermatitis, stasis dermatitis, and psoriasis.
Neoplastic
Malignant skin cancers: squamous cell carcinoma, basal cell carcinoma, and malignant melanoma (the most dangerous).
Benign neoplasms: include keratosis and keratoacanthoma.
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FIGURE 37.2 Anatomical distribution of common skin disorders: (a) contact dermatitis due to footwear, (b) cosmetics, (c) seborrheic dermatitis, (d) acne, (e) scabies, (f) sunburn.
SKIN PARASITES
Common skin parasites include mites and lice. Mites cause a skin disorder called scabies, based on their scientific name, Sarcoptes scabiei. Scabies is an eruption of the skin caused by the female mite burrowing into the skin and laying eggs. This causes intense itching, most commonly between the fingers, on the extremities, and around the trunk and pubic area. Scabies is readily spread among family members and sexual partners.
Lice, scientific name Pediculus, are another type of skin parasite readily passed on by infected clothing or close personal contact. Lice often infest the pubic area or the scalp and lay eggs that attach to body hairs.
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Fast Facts Skin Disorders in the United States
* An estimated 6 to 11 million children between the ages of 3 and 11 are infected with lice each year.
* Nearly 40 to 50 million people have some form of acne, making it the most common skin disease.
* More than 31.6 million people have eczema, and at least 17.8 million people have moderate to severe eczema or atopic dermatitis.
* Ten percent of infants and young children experience symptoms of dermatitis. Roughly 60% of these infants continue to have symptoms in adulthood.
* More than 7.5 million people have psoriasis. This disorder occurs in all age groups –adults mainly — affecting about the same number of men as women.
Core Concept 37.3***
Scabicides and pediculicides treat parasitic mite and lice infestations.
Scabicides are pharmacologic agents that kill mites; pediculicides kill lice. Either treatment may be effective for both types of parasites. The preferred drug often depends on where the infestation has occurred.
The preferred drug for lice infestation is permethrin, a chemical derived from chrysanthemum flowers and formulated as a 1% liquid (Nix). This drug is considered the safest agent, especially for infants and children. Pyrethrin (RID, others) is a related product also obtained from the chrysanthemum plant. Permethrin and pyrethrins, which are also widely used as insecticides on crops and livestock, kill lice and their eggs on contact. Malathion (Ovide) is an alternative drug treatment. Because of toxicity concerns, patients often ask about natural or home remedies. There are many common remedies for pediculicides, including vinegar, cranberry juice, and plant oils such as olive and coconut. Even Listerine mouthwash can help with lice or mite infestation.
Permethrin is a preferred drug for scabies. The 5% permethrin cream (Elimite) is applied to the entire skin surface and allowed to remain for 8 to 14 hours before bathing. Itching may continue for several weeks as the dead mites are removed from the skin. Crotamiton (Eurax) is an alternative scabicide available by prescription as a 10% cream. Approved in 2012, ivermectin (Sklice) is a lotion that is left on the scalp for 10 minutes and does not require a nit comb following treatment. Because lindane (Kwell) has the potential to cause serious nervous system toxicity, it is now prescribed only after other less toxic drugs have failed to produce a therapeutic response.
All scabicides and pediculicides must be used strictly as directed, because excessive use has the potential to cause serious systemic effects and skin irritation. Drugs for the treatment of lice or mites must not be applied to the mouth, open skin lesions, or eyes, because this will cause severe irritation.
Lice lay eggs called nits. Fine-toothed nit combs are useful in removing nits after the lice have been killed. Patients should comb the infested area after the hair has been dried. To ensure that drug therapy is effective, patients should inspect hair shafts daily for at least 1 week after treatment. Because nits may be present in bedding and other upholstery material, all material coming in close contact with the patient should be washed or treated with the medication.
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Prototype Drug: ***Permethrin (Acticin, Elimite, Nix)
Therapeutic Class: Antiparasitic drug Pharmacologic Class: Scabicide, pediculicide
Actions and Uses: Nix is marketed as a cream or shampoo to kill head and crab lice. It will also kill mites and eradicate their ova. A 1 % lotion is approved for lice and 5% lotion for mites. The medication should be allowed to remain on the hair and scalp 10 minutes before removal. Patients should be aware that Itching may last up to 2 or 3 weeks even after parasites have been killed. Successful elimination of parasitic infestations should include removing the nits with a comb, washing bedding, and cleaning or removing objects that have been in contact with the head or hair.
Adverse Effects and Interactions: Permethrin causes few systemic effects. Local reactions may occur and Include pruritus, rash, transient tingling, burning, stinging, erythema, and edema of the infested area.
Contraindications include hypersensitivity to pyrethrins, chrysanthemums, sulfites, or other preservatives. Permethrin should be used cautiously on inflamed skin, in those with asthma, or in lactating women. No significant clinical drug interactions have been documented.
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* Name examples of medications used to treat mite and lice infestations. What precautions should be taken when using these medications?
Nursing Process Focus Patients Receiving Pharmacotherapy for Lice or Mite Infestation
ASSESSMENT
POTENTIAL NURSING DIAGNOSES*
Prior to drug administration:
* Obtain a complete health history, including age, dermatological conditions, social history and close contacts, allergies, drug history, and possible drug interactions.
* Examine skin areas to be treated for signs of infestation (e.g., lice or nits in hair, reddened track areas between web of fingers, around the belt or elastic lines), irritation, excoriation, or drainage.
* Deficient Knowledge related to a lack of information about condition and drug therapy regimen
* Impaired Health Maintenance related to treatment regimen
* Risk for Impaired Skin Integrity related to infestation or adverse effects of drug therapy
* Risk for Poisoning related to adverse effects of drug therapy
PLANNING: PATIENT GOALS AND EXPECTED OUTCOMES
The patient will:
* Experience therapeutic effects (free of lice or mites).
* Be free from or experience minimal adverse effects from drug therapy.
* Verbalize an understanding of how lice and mites are spread; proper administration of medication; necessary household hygiene; and the need to notify household members, sexual partners, and other close contacts (such as classmates) about infestation.
IMPLEMENTATION
Interventions and (Rationales)
Patient Education/Discharge Planning
*Apply medication correctly and evaluate the patient’s and caregiver’s knowledge of proper administration. (Everyone in the household with mites or lice should be treated at the same time. Proper application is critical to eliminate the infestation.)
Instruct the patient and family members:
* That all skin lotions, creams, and oil-based hair products should be removed completely before applying medication.
* To apply the drug per package directions and allow It to remain in the hair or on the skin for the prescribed length of time (approximately 10 minutes).
* To use a fine-toothed comb to remove any remaining dead lice or mites.
* That eyelashes can be treated with the application of petroleum jelly once a day for 1 week. Use a fine-toothed comb to remove mites.
* To recheck affected hair or skin daily for at least 1 to 2 weeks after treatment.
*Monitor the skin and head areas for infestation over the next 1 to 2 weeks. Reinfestations may appear within 1 week, and retreatment may be necessary. (Monitoring helps to determine proper medication administration technique and compliance with prevention protocols.)
Instruct the patient and family members to:
* Monitor for nits on hair shafts; lice on skin or clothes, inner thigh areas, and seams of clothes that come in contact with axilla, neckline, or beltline.
* Monitor for mites between the fingers, on the extremities, in the axillary and gluteal folds, around the trunk, and in the pubic area.
*Monitor household for signs of infestation. Inform the patient and others living in the home about proper care of clothing and equipment. (Contaminated articles can cause reinfestation.)
Instruct the patient and family members to:
* Wash all bedding and clothing in hot water, and to dry-clean all nonwashable items that came in close contact with the patient.
* Vacuum furniture or fabric that cannot be cleaned, and seal children’s toys in plastic bags for 2 weeks.
* Not share personal care Items such as combs, brushes, and towels.
* Clean combs and brushes, and rinse thoroughly after every use.
EVALUATION OF OUTCOME CRITERIA
Evaluate the effectiveness of drug therapy by confirming that patient goals and expected outcomes have been met (see “Planning”).
***Herdman, T.H. & Kamitsuru, S. (Eds.), Nursing Diagnoses: Definitions & Classification 2015-2017. Copyright © 2014, 1994-2014 NANDA International. Used by arrangement by John Wiley & Sons, Inc. Companion website: www.wiley.com/go/nursingdiagnoses.
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sebor = oil
rhea = flow
SUNBURN AND MINOR SKIN IRRITATION Core Concept 37.4***
The goal of drug therapy for sunburn is to eliminate discomfort until healing occurs.
Sunburn, a common problem among the general public, is associated with factors such as light skin complexion and lack of proper sun protection. Nonpharmacologic approaches to sun protection include the appropriate use of sunscreens, sunglasses, and sufficient clothing. Limiting the amount of time spent directly in the sun is essential to avoiding sunburn. Many dangers result from sun exposure, including eye injury and skin cancer. Some of these disorders may not appear until years after the exposure.
Pharmacologic treatments for sunburn may not be necessary. Remaining calm until the minor irritation passes is one common approach to mild sunburn. In cases in which pharmacologic intervention is necessary, drugs for sunburn and minor irritation include mild lotions and topical anesthetics such as benzocaine (Solarcaine, others), dibucaine (Nuper-cainal), and tetracaine (Pontocaine). These are used to provide temporary relief of painful symptoms. Some of these medications may also provide minor relief from insect bites and pruritus. In cases of more lengthy sun exposure, more potent pain medications may be administered (see Chapters 15 and 25), or tetanus toxoid might be administered to prevent infection (see Chapter 27).
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Prototype Drug: *** Benzocaine (Américaine, Anbesol, Others)
Therapeutic Class: Agent for sunburn pain and minor skin irritations Pharmacologic
Class: Local anesthetic, sodium channel blocker
Actions and Uses: Benzocaine provides temporary relief for pain and discomfort in cases of sunburn, pruritus, minor wounds, and insect bites. Its pharmacologic action is caused by local anesthesia of skin receptor nerve endings. Preparations are also available to treat the skin and other areas such as the ear, mouth, throat, rectal, and genital areas.
Adverse Effects and Interactions: Benzocaine should not be used for treatment of patients with open lesions, traumatized mucosal areas, or a history of drug sensitivity. Benzocaine may-‘ interfere with the activity of some antibacterial sulfonamides. Patients should use preparations only in areas of the body for which the medication is intended.
CONCEPT REVIEW 37.3
* What is the major purpose of drugs used to treat sunburn, insect bites, and related injuries? What major class of drugs would be used for this purpose?
ACNE AND ROSACEA
Acne, sometimes called acne vulgaris, is a common condition found most often in adolescents and young adults. The disorder usually begins 1 or 2 years before puberty and is caused by overproductive oil glands or seborrhea. Acne is also caused by abnormal keratinization or development of the horny layer of the epithelial tissue of skin. This activity results in blocked oil glands. Administration of androgens or testosterone-like hormones may cause extensive acne by increasing keratinization and the production of sebum (oil). Following this, the bacterium Propionibacterium acnes grows within gland openings and modifies the sebum into an acidic and irritating substance. As a result, small inflamed bumps appear on the surface of the skin. Aggravating factors can trigger or make worse an existing case of acne. These include changing hormone levels, some medications (corticosteroids, androgens, or lithium), foods (chocolate, dairy, or carbohydrate-rich products), and stress.
Blackheads, or open comedones, are a type of acne in which sebum has plugged the oil gland, causing it to become black because of the presence of melanin granules. Whiteheads, or closed comedones, are a type of acne that develops just beneath the surface of the skin and appears white rather than black. In more severe cases of acne, deeper bumps called nodules may appear and become very painful because of the intense inflammation and pus found within pore pockets.
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Another skin disorder characterized by inflammation but without pus is rosacea. Unlike pimples or pustules –the technical name given to pus-filled bumps –rosacea is characterized by small papules or inflammatory bumps that swell, thicken, and become very painful. Characteristic of rosacea is its swelling just beneath the surface of the skin. The face of a patient with rosacea may take on a flushed appearance, particularly around the nose and cheek area. Rosacea is exacerbated by many factors, including sunlight, stress, increased temperature, and agents that dilate facial blood vessels such as alcohol, spicy foods, and warm beverages.
*** Core Concept 37.5
Acne and rosacea are treated by a combination of over-the-counter and prescription drugs.
Most acne drugs slow down the turnover of skin cells, especially those surrounding pore openings. Some inhibit bacterial growth because they are combined with antibiotics such as doxycycline and tetracycline (see Chapter 27). Some drugs must be used carefully because of their ability to dramatically reduce oil gland activity and skin cell turnover. Important medications for acne and rosacea are summarized in Table 37.3.
Benzoyl peroxide (Clearasil, Fostex, others) is one of the primary OTC medications used to treat acne. This medication may be dispensed as a lotion, cream, or gel and is available in various concentrations. Benzoyl peroxide decreases symptoms of acne by inhibiting bacterial growth and suppressing the turnover of skin cells at the pore’s opening. Applied directly to affected skin, it is relatively safe, with redness, irritation, and drying being the most common adverse effects. Patients usually see some improvement in the first week, but it may take weeks, even a month or longer, to notice the full effect. Sometimes benzoyl peroxide is combined with antibiotics to directly fight bacterial infections. When acne is particularly severe, resorcinol, salicylic acid, or sulfur may be used as additional treatments to promote shedding of old skin. These are called keratolytic agents.
Retinoids are vitamin A-like compounds used for acne. Vitamin A provides improved resistance to bacterial infection by reducing oil production and the occurrence of clogged pores.
Table 37.3 Drugs for Acne and Rosacea
Drug
Remarks
OTC MEDICATION-TOPICAL PREPARATION
benzoyl peroxide (Clearasil, Fostex, others)
Often combined with erythromycin or clindamycin to fight bacterial infection (see Chapter 27)
PRESCRIPTION MEDICATIONS-TOPICAL
adapalene (Differin)
Retinoid-like compound used to treat acne formation
azelaic acid (Azelex, Finacea, others)
For mild to moderate inflammatory acne and rosacea
brimonidine (Mirvaso)
For persistent facial erythema of rosacea
clindamycin and tretinoin (Veltin, Ziana)
Combination product with an antibiotic and retinoid in a gel base, for mild to moderate acne
ivermectin (Soolantra)
For inflammatory lesions of rosacea
metronidazole (Metrogel, MetroCream)
For inflammatory papules and pustules of rosacea
sulfacetamide sodium (Cetamide, Klaron, others)
For sensitive skin; sometimes combined with sulfur to promote peeling, as in rosacea; also used for conjunctivitis
tazarotene (Avage, Tazorac)
A retinoid drug that may also be used for plaque psoriasis; has antiproliferative and antiinflammatory effects
***tretinoin (Avita, Retin-A, others)
A retinoid used to prevent clogging of pore follicles associated with acne; the oral form (Vesanoid) is used to treat acute promyelocytic leukemia and wrinkles
PRESCRIPTION MEDICATIONS-ORAL
doxycycline (Vibramycin, others)
Antibiotic (see Chapter 27)
ethinyl estradiol and norgestimate
Oral contraceptives are sometimes used for acne treatment; combination drugs may be helpful, for example, ethinyl estradiol plus norgestimate or Ortho Tri-Cyclen-28 (see Chapter 35)
isotretinoin
A retinoid used for severe acne with cysts or acne formed in small, rounded masses; pregnancy category X
minocycline (Minocin, others)
Antibiotic (see Chapter 27)
tetracycline (see the Prototype Drug box in Core Concept 27.8)
Antibiotic (see Chapter 27)
[sidebar]
kerato = horny layer
lytic = loosening
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dermat = skin
itis = inflammation
atopic = out
Retinoids are not recommended during pregnancy because of possible harmful effects to the fetus. A common reaction to retinoids is sensitivity to sunlight.
Some drugs may be taken in combination with or in lieu of other acne medications, including doxycycline, tetracycline, and ethinyl estradiol. Doxycycline and tetracycline are antibiotics used to inhibit bacterial growth (see Chapter 27). Oral contraceptives containing ethinyl estradiol may be used to help clear the skin of acne by suppressing oil production (see Chapter 35).
The two most effective treatments for rosacea are topical metronidazole (Metrogel, MetroCream) and azelaic acid (Azelex, Finacea). Alternative medications include topical clindamycin (Cleocin-T, ClindaMax) and sulfacetamide. Tetracycline antibiotics are beneficial to patients with rosacea with multiple pustules or with ocular involvement. Severe, resistant cases may respond to isotretinoin.
CONCEPT REVIEW 37.4
* What is the major purpose of drugs used to treat acne and related skin conditions? Give examples of both topical and systemic medications. Which medications are OTC, and which are prescription medications?
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Prototype Drug: *** Tretinoin (Avita, Retin-A, Others)
Therapeutic Class: Antiacne drug Pharmacologic Class: Retinoid receptor drug, vitamin derivative
Actions and Uses: The topical forms of tretinoin are indicated for control of mild to moderate acne vulgaris. Symptoms take 4 to 8 weeks to improve, and maximum therapeutic benefit may take up to 5 or 6 months. This drug is most often reserved for cystic acne or severe keratinization disorders. Renova is a tretinoin cream approved to treat fine facial wrinkles.
The principal action of tretinoin is regulation of skin growth and cell turnover. As cells from the germinativum grow toward the skin’s surface, skin cells are lost from the pore openings, and their replacement is slowed down. Tretinoin also decreases oil production by reducing the size and number of oil glands.
Adverse Effects and Interactions: Tretinoin is a natural derivative of retinol or vitamin A. Thus, vitamin A supplements, which increase toxicity, should be avoided.
Common adverse effects are skin irritation (such as a burning or stinging sensation, redness, and crusting), conjunctivitis (visual disturbance), dry mouth, Inflammation of the lip, dry nose, increased serum concentrations of triglycerides, bone and joint pain, and photosensitivity. Additive phototoxicity can occur if tretinoin is used concurrently with other photo-toxic drugs such as tetracyclines, fluoroquinolones, or sulfonamides.
Using tretinoin together with hypoglycemic agents may lead to loss of glycemic control as well as increased risk of cardiovascular disease due to elevated triglyceride levels.
BLACK BOX WARNING:
Patients with acute promyelocytic leukemia (APL) are at high risk for serious adverse effects: fever, weakness, fatigue, dyspnea, weight gain, peripheral edema, respiratory insufficiency, pneumonia, and rapidly evolving leukocytosis, which is associated with a high risk of life-threatening complications. There is a high risk that infants will be severely deformed if this drug is administered during pregnancy.
DERMATITIS AND ECZEMA
Dermatitis is a general term that refers to superficial inflammatory disorders of the skin,
Eczema, also called atopic dermatitis, is a skin disorder with symptoms resembling an allergic of place reaction, including inflammation, itching, and rash. Long-term itching and scaling may cause the skin to appear thickened and leathery. Exposure to environmental irritants may make these symptoms worse. Other conditions, including stress, too little or too much moisture, and extreme temperature fluctuations, may worsen symptoms. Blisters and other lesions may also develop. In infants and small children, lesions usually begin on the face and progress to other parts of the body. The skin may become raw and infected from scratching.
Contact dermatitis is a delayed type of allergic reaction resulting from exposure to specific allergens –for example, perfume, cosmetics, detergents, latex, or jewelry. Accompanying the allergic reaction may be various degrees of cracking, bleeding, or small blisters.
Seborrheic dermatitis is a disorder caused by overactive oil glands. This condition is sometimes seen in newborns and in teenagers after puberty. Oily and scaly patches of skin appear in areas of the face, scalp, chest, back, or pubic area. Bacterial infection or dandruff may accompany these symptoms.
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Stasis dermatitis is seen more commonly in older women. It is found primarily in the lower extremities. Redness and scaling may be observed in areas where venous circulation is impaired or where deep venous blood clots have formed.
*** Core Concept 37.6
Topical corticosteroids are used mainly to treat dermatitis and related symptoms.
Topical corticosteroids are used in cases of dermatitis and eczema to treat symptoms of inflammation, burning, and pruritus. In conjunction with other medical therapies, topical corticosteroids are also used for the treatment of psoriasis.
Topical corticosteroids are the most effective treatment for dermatitis. As seen in Table 37.4, there are many varieties of corticosteroids supplied at different levels of potency. Creams, lotions, solutions, gels, and pads are specially formulated to cross skin membranes.
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CAM Therapy | Aloe Vera for Skin Conditions
Aloe vera is derived from the gel inside the leaf of the aloe plant, which is a member of the lily family. Used medicinally for thousands of years, aloe vera contains over 70 active substances, including amino acids, minerals, vitamins, and enzymes. Aloe vera is best known for its ability to soothe and heal minor skin irritations, cuts, and burns. For the most part, scientific studies have confirmed its benefit for these conditions. It can be found as an ingredient in many products, including soaps, lotions, creams, and sunblocks. Some evidence suggests it may be useful in treating genital herpes lesions and moderate plaque psoriasis. Although oral formulations can be found, these are not recommended because they can cause serious gastrointestinal (GI) side effects.
Table 37.4 Selected Topical Corticosteroids for Dermatitis and Related Symptoms
VERY HIGH POTENCY
betamethasone dipropionate
Diprolene
clobetasol
Temovate
diflorasone
Maxiflor
halobetasol
Ultravate
HIGH POTENCY
amcinonide
Cyclocort
fluocinonide
Lidex
halcinonide
Halog
MEDIUM POTENCY
betamethasone benzoate
Uticort
betamethasone valerate
Valisone
clocortolone
Cloderm
desoximetasone, cream
Topicort
fluocinolone acetonide
Synalar
flurandrenolide, cream
Cord ran
fluticasone propionate, cream
Cutivate
hydrocortisone valerate
Westcort
mometasone furoate
Elocon
prednicarbate
Dermatop
triamcinolone acetonide
Aristocort, Kenalog
LOWER POTENCY
alclometasone dipropionate
Aclovate
desonide
Desonate, DesOwen, Verdeso
dexamethasone
hydrocortisone
Cortizone, Hycort
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emolli = to soften
ent = causing.
These medications are especially intended for the relief of local inflammation and itching. In cases of long-term use, however, adverse effects such as irritation, redness, and thinning of the skin membranes may occur. If absorption occurs, topical corticosteroids may produce undesirable systemic effects, including adrenal insufficiency, mood changes, serum imbalances, and bone defects, as discussed in Chapter 25.
PSORIASIS
Psoriasis is a chronic, noninfectious inflammatory skin disorder that affects 1% to 2% of the U.S. population each year. Psoriasis is characterized by red patches of skin covered with flaky, silver-colored scales called plaques. The reason for the appearance of plaques is an extremely fast skin turnover rate. The skin reacts as if it has been injured, but skin cells reach the surface much more quickly than usual, in about 4 days, or six to seven times faster than usual. The reason for this kind of reaction is not known, although scientists believe that it may be a genetic immune reaction. Plaques are ultimately shed from the skin’s surface, while the underlying skin becomes inflamed and irritated.
Core Concept 37.7***
Several topical and systemic medications are used to treat psoriatic symptoms.
Because psoriatic symptoms may be extreme, numerous drugs are employed to soothe the patient’s symptoms, including emollients, topical corticosteroids, and immunosuppressants
Drugs used in the treatment of psoriasis are provided in Table 37.5.
Topical corticosteroids, such as betamethasone or hydrocortisone, are the primary, initial treatment for psoriasis because they are effective, safe, and inexpensive. Topical corticosteroids reduce the inflammation associated with fast skin turnover. Therapy usually begins with the high potency corticosteroids and switches to moderate- and low-potency agents after the initial symptoms have been controlled.
Other topical drugs are retinoid-like compounds such as calcipotriene (Dovonex) and tazarotene (Tazorac). These drugs provide the same benefits as topical corticosteroids, but they exhibit fewer side effects. Calcipotriene produces elevated levels of calcium in the bloodstream, so this medication is not used on an extended basis. Enstilar is a newer drug that consists of a combination of calcipotriene and beclomethasone.
Some patients have severe psoriasis that is resistant to topical drugs, so systemic therapy must be used. Systemic medications for psoriasis include acitretin (Soriatane), adalimumab (Humira), alefacept (Amevive), apremilast (Otezla), etanercept (Enbrel), infliximab (Remicade), secukinumab (Consentyx), and ustekinumab (Stelara). These drugs are taken orally to inhibit skin cell growth. Methotrexate (Rheumatrex, Trexall), an anticancer drug taken in tablet form, also inhibits cell growth (see Chapter 29). Other medications that have been used for different disorders but may provide relief of severe psoriatic symptoms are hydroxyurea and cyclosporine (Sandimmune, Neoral). Cyclosporine is an immunosuppressant, discussed in Chapter 26.
Other skin therapy techniques may be used with or without psoriasis medications. These include various forms of tar treatment (coal tar) and a material called anthralin. Both substances are applied to the skin’s surface and are not considered first-line therapies. Tar and anthralin inhibit DNA synthesis and arrest abnormal cell growth.
Ultraviolet B (UVB) and ultraviolet A (UVA) phototherapy are techniques used in cases of severe psoriasis. UVB therapy is less hazardous than UVA therapy. UVB light has a wavelength similar to sunlight; it reduces widespread lesions that normally resist topical treatments. With close supervision, this type of phototherapy can be administered at home. Keratolytic pastes are often applied between treatments. The second type of phototherapy is often referred to as PUVA (psoralen plus ultraviolet light) therapy because psoralens are often administered in conjunction with phototherapy. Psoralens are oral or topical agents that, when exposed to UV light, produce a photosensitive reaction. This reaction seems to provide benefit to the patient by reducing the number of lesions, but unpleasant adverse effects such as headache, nausea, and skin sensitivity may occur, limiting the effectiveness of this therapy. Immunosuppressant drugs such as cyclosporine are not used in conjunction with PUVA therapy because they increase the risk of skin cancer.
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Table 37.5 Drugs for Psoriasis and Related Disorders
Drug
Route and Adult Dose
Remarks
TOPICAL MEDICATIONS
anthralin (Dritho-Scalp)
Topical: Apply to lesions of the scalp as directed
Second-line therapy after tolerance to corticosteroids has developed
calcipotriene (Dovonex)
Topical: Apply to lesions once or twice daily up to 8 weeks
Synthetic form of vitamin D3; may raise the level of calcium in the body to unhealthy levels
Coal tar (Balnetar, Cutar, others)
Topical: Apply to lesions daily or as directed
Second-line therapy after tolerance to corticosteroids has developed
salicylic acid (Salax, Neutrogena, others)
Topical: Apply to lesions (concentrations ranging from 2-10%) as directed
Wide range of delivery: creams, foams, gels, lotions, ointments, pads, plasters, shampoos, soaps, and skin solutions
tazarotene (Tazorac)
Acne: Topical: Apply thin film to clean, dry area daily Plaque psoriasis: Topical: Apply a thin film daily in the evening
Topical retinoid; less toxic than corticosteroids; also approved for facial wrinkles and acne
SYSTEMIC MEDICATIONS
acitretin (Soriatane)
PO: 10-50 mg/day with the main meal
Retinoid; pregnancy category X drug
adalimumab (Humira)
Subcutaneous: 40-80 mg every other week
Tumor necrosis factor blocker; also for rheumatoid arthritis and Crohn disease
alefacept (Amevive)
IM: 15 mg once weekly for 12 weeks
Engineered immunosuppressant drug
apremilast (Otezla)
PO: Begin with 10 mg per day and increase over 6 weeks to 30 mg bid
Phosphodiesterase-4 (PDE-4) inhibitor for the treatment of moderate-to-severe plaque psoriasis
cyclosporine (Gengraf, Neoral, Sandimmune) (see the Prototype Drug box in Core Concept 26.5)
PO: 1.25 mg/kg bid (max: 4 mg/kg/day)
Immunosuppressant drug; also to prevent transplant rejection and for rheumatoid arthritis
etanercept (Enbrel)
Subcutaneous: 50 mg twice weekly (given 3-4 days apart); maintenance dose 50 mg/week
Also for rheumatoid arthritis
infliximab (Remicade)
IV: 5 mg/kg with additional doses 2 and 6 weeks after the initial infusion, then every 8 weeks thereafter
Tumor necrosis factor blocker; also for rheumatoid arthritis, Crohn disease, and ulcerative colitis
hydroxyurea
PO: 80 mg/kg every 3 days or 20-30 mg/kg daily
Alternative treatment for psoriasis; oral cancer medication
ixekizumab (Taltz)
Subcutaneous: 160 mg initially, then 80 mg at weeks 2, 4, 6, 8, and 12
Newer drug; interleukin-17A inhibitor
methotrexate (Otrexup Rheumatrex, Trexall) (see the Prototype Drug box in Core Concept 29.8)
PO: 2.5-5 mg bid x 3 doses each week (max: 25-30 mg/week)
Subcutaneous (Otrexup): 7.5-20 mg once/week
Also for rheumatoid arthritis and neoplasia
secukinumab (Consentyx)
Subcutaneous: 150-300 mg at weeks 0,1,2,3,4 followed by 300 mg every 4 weeks
lnterleukin-17A inhibitor approved for adults with ankylosing spondylitis and psoriatic arthritis
ustekinumab (Stelara)
Subcutaneous: 45-90 mg initially and 4 weeks later, followed by 45-90 mg every 12 weeks
Interleukin blocker
* In most cases, which drug category is used to treat symptoms of dermatitis and psoriasis? What other drug therapies and techniques are used to provide a measure of relief for these symptoms?
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Patients Need to Know
Patients taking medications for skin disorders need to know the following:
1. Inform family members, sexual partners, school personnel, and any other persons with whom close contact has occurred about skin infestations. Treat clothes, bed linens, and personal items properly to avoid reinfestation.
2. Be informed and understand the proper way to apply medication or to remove nits if necessary. Scabicides and pediculicides should not be applied to the face, mouth, or eyes, or open skin lesions.
3. For acne and related disorders, apply medication only to areas where it is supposed to be applied. Follow instructions in package inserts and do not deviate from the precautions communicated by the healthcare provider.
4. Do not share skin medications with family or friends. Be familiar with medication adverse effects, especially those of retinoids, retinoid-like products, or medications used to treat severe skin disorders.
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5. Use medications only during the time for which they are intended. With extended use, some medications (e.g., corticosteroids) may cause adverse effects. Take a medication suitable for the disorder; avoid those that are too potent or not potent enough.
6. Give medications a chance to work. Some systemic medications must be taken exactly as prescribed without skipping or stopping early.
7. Avoid contact with objects or drugs that are known to cause allergy or dermatitis. Try to avoid scratching, if possible. For severe skin disorders, see a dermatologist.
Chapter Review Core Concepts Summary
37.1 Layers of skin provide protection to the body.
Two layers of skin and one underlying layer protect the body: the epidermis, dermis, and hypodermis. The most superficial layer is the epidermis, in which skin cells are replenished every 3 weeks. New cells arise from the bottom layer of the epidermis, called the germinativum, and are pushed to the outermost layer.
37.2 The major causes of skin disorders are injury, aging, inherited factors, and other medical conditions.
Many symptoms are associated with skin stress and injury. Others are associated with a patient’s changing age or health. Skin disorders fit into three main categories: infectious, inflammatory, and cancerous disorders.
37.3 Scabicides and pediculicides treat parasitic mite and lice infestations.
Mites affect the skin and hair, whereas lice remain localized in hairy regions of the body. Both conditions are treatable with medications. Scabicides kill mites; pediculicides kill lice.
37.4 The goal of drug therapy for sunburn is to eliminate discomfort until healing occurs.
Local anesthetics are the primary medication used to treat mild sunburn and irritation. Often drugs are used for temporary relief of minor discomfort; in some cases, drugs may not be needed at all.
37.5 Acne and rosacea are treated by a combination of over-the-counter and prescription drugs.
Blackheads, whiteheads, and rosacea are disorders in which pores become blocked, inflamed, or infected because of accelerated skin processes. Topical drugs for acne are those that inhibit bacterial growth (antibiotics) or promote shedding of old skin (keratolytic agents). Vitamin A-like compounds (retinoids) provide an improved resistance to bacterial infections by reducing oil production and the occurrence of clogged pores.
37.6 Topical corticosteroids are used mainly to treat dermatitis and related symptoms.
Dermatitis is treated by agents that reduce symptoms of inflammation, itchiness, flaking, cracking, bleeding, and lesions. Topical corticosteroids are the primary drug treatment for dermatitis. Potency depends on the type of drug formulation and whether it is packaged as a cream, lotion, solution, gel, or pad.
37.7 Several topical and systemic medications are used to treat psoriatic symptoms.
Psoriasis is a chronic disorder characterized by extreme discomfort and flaky areas called plaques. The treatments for psoriasis include topical corticosteroids, retinoid-like compounds, drugs that arrest skin cell growth, and immunosuppressants. Skin therapy techniques are also used, including keratolytic agents, coal tar, anthralin, psoralens, and phototherapy.
2. The nurse is helping to create a teaching plan for a patient prescribed desoximetasone (Topicort) for atopic dermatitis. Which adverse effect will be included in that plan?
1. Localized pruritus and hives
2. Hair loss in the application area
3. Worsening of acne
4. Skin irritation and redness in the application area
REVIEW Questions
Answer the following questions to assess your knowledge of the chapter material, and go back and review any material that is not clear to you.
1. Which of the following is true regarding the use of benzocaine for a minor skin irritation?
1. It cannot be used for sunburns.
2. It should not be used on open lesions.
3. It causes blisters.
4. It can be used on open sores.
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3. The nurse and a patient are discussing how to eliminate lice. The patient is given a shampoo-like medication that is applied and rinsed from the body within 10 minutes after application. This medication is:
1. Lindane.
2. Crotamiton.
3. Cortizone.
4. Permethrin.
4. The patient is complaining of discomfort related to minor sunburn. Which of the following medications would be included in a plan of care for someone who has minor sunburn?
1. Benzocaine (Solarcaine)
2. Cortizone
3. Benzoyl peroxide
4. Doxycycline
5. The nurse is providing information at a high school health fair. Many of the students ask for information on acne treatment. The nurse tells them that_is available but it is extremely important that women who are pregnant do not take this medication.
1. Hydrocortisone
2. Tretinoin
3. Benzoyl peroxide
4. Benzocaine
6. The patient using topical corticosteroids will need to be monitored for which of the following systemic effects? (Select all that apply.)
1. Mood changes
2. Bone defects
3. Liver toxicity
4. Adrenal insufficiency
5. Skin irritation
7. A patient with rosacea has been treating her condition with over-the-counter medications, but they have worsened her condition. The healthcare provider understands the patient may need:
1. Calcipotriene (Dovonex).
2. Metronidazole (Metrogel).
3. Acitretin (Soriatane).
4. Cyclosporine (Sandimmune, Neoral).
8. Some patients with acne may need medications that promote the shedding of old skin. These medications are known as:
1. Pediculicides.
2. Keratolytic agents.
3. Retinoids.
4. Corticosteroids.
9. The skin on the elbow of a newly diagnosed patient with psoriasis is covered with red plaques and scales. The patient finds it very embarrassing and wants to know the most cost effective medication that can help her. The nurse understands that the initial and inexpensive medication is:
1. Betamethasone.
2. Doxycycline.
3. Cyclosporine.
4. Benzocaine.
10. A patient weighing 198 pounds is to receive the initial infused dose of infliximab (Remicade), 5 mg/kg. How many milligrams will the patient receive?
1. 45 mg
2. 90 mg
3. 450 mg
4. 990 mg
CASE STUDY Questions
[Image: Burt Nicholson.]
Remember Burt Nicholson, the patient introduced at the beginning of the chapter? Now read the remainder of the case study. Based on the information you have learned in this chapter, answer the questions that follow.
Burt Nicholson is a 16-year-old White male with a family history of various allergy disorders. He is complaining of general irritation and sores around the face, neck, and upper back. Upon examination, a severe case of acne and moderate erythema are observed on the chin, cheeks, and forehead. No excessive oil is noted. Although areas around the neck and upper back are inflamed, these do not appear to be infected. Burt states that he is so embarrassed about his skin, it is impacting his social life. He also says that he has tried many different OTC medications but nothing seems to work. Burt is diagnosed with acne vulgaris.
1. The nurse asks Burt which medications he tried. He says that he cannot remember all of them but is sure he tried benzoyl peroxide, which he stopped using after a week because his acne was still visible. The nurse responds by saying:
1. “The cream should have worked within that first week.”
2. “Improvements begin in the first week but the full effects may take several weeks to a month or longer.”
3. “Acne is very difficult to treat. It may take several months before you see improvements.”
4. “If your acne is not gone by now, you may need an antibiotic.”
2. The healthcare provider wants Burt to try the benzoyl peroxide again, but because Burt’s skin is red and inflamed, the nurse suspects that a(n)_will also be prescribed.
1. Metronidazole
2. Benzocaine
3. Corticosteroid
4. Antibiotic
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3. Other medication options are discussed. Burt is informed that he could also take tretinoin, a retinoid antiacne medication. When asked how the medication works, the nurse responds that tretinoin:
1. Sheds the outer layer of the skin.
2. Decreases oil production by reducing the size and number of oil glands.
3. Inhibits bacterial growth.
4. Reduces inflammation.
4. The nurse continues to tell Burt that tretinoin may cause the following adverse effects: (Select all that apply.)
1. Swelling around the lips
2. Dry mouth and nose
3. Photosensitivity (sensitivity to light)
4. Skin irritation such as burning and redness
Answers and complete rationales to the Review and Case Study Questions appear in Appendix A.
REFERENCE
Herdman, T. H., & Kamitsuru, S. (Eds.). (2014). NANDA International nursing diagnoses: Definitions and classification, 2015-2017. Oxford, United Kingdom: Wiley-Blackwell.
SELECTED BIBLIOGRAPHY
American Academy of Dermatology, (n.d.). Acne. Retrieved from
https://www.aad.org/media/stats/conditions American Academy of Dermatology, (n.d.). Psoriasis. Retrieved from https://www.aad.org/public/diseases/scaly-skin/psoriasis
Bradby, C. (2014). Atopic dermatitis in emergency medicine. Retrieved from http://emedicine.medscape.com/article/762045- overview#a0199
Centers for Disease Control and Prevention. (2013). Epidemiology and risk factors. Retrieved from http://www.cdc.gov/parasites/lice/ head/epi.html
The Children’s Hospital of Philadelphia, (n.d.). Atopic dermatitis in childhood. Retrieved from http://www.chop.edu/conditions-diseases/atopic-dermatitis-children#. VTxggPkrlhc Guenther, L. C. (2016). Pediculosis and pthiriasis (lice infestation). Retrieved from http://emedicine.medscape.com/article/225013-overview#a0156
Meffert, J. (2015). Psoriasis. Retrieved from http://emedicine.med-scape.com/article/1943419-overview National Eczema Association, (n.d.). Eczema prevalence in the United States. Retrieved from https://nationaleczema.org/research/eczema-prevalence National Psoriasis Foundation, (n.d.). Facts about psoriasis. Retrieved from https://www.psoriasis.org/teens/about-psoriasis
Radtke, M. A., Reich, K, Spehr, C, & Augustin, M. (2015). Treatment goals in psoriasis routine care. Archives of Dermatological Research, 307,445-449. doi:10.1007/s00403-014-1534-y
Rao, J. (2015). Acne vulgaris. Retrieved from http://emedicine.med-scape.com /article/1069804-overview
Tüzün, Y., Wolf, R., Kutlubay, Z., Karakus, Ö., & Engin, B. (2014). Rosacea and rhinophyma. Clinics in Dermatology, 32, 35-46. doi:10.1016/j.clindermatol.2013.05.024
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Chapter 38 Drugs for Eye and Ear Disorders
[Image: Ms. Mary Saunders.]
“Moving is so stressful, and it’s worse because I haven’t had any help. I’m not even sure where I packed my medication so I’ve been having problems seeing.”
Ms. Mary Saunders
Core Concepts
38.1 Knowledge of basic eye anatomy is essential for an understanding of eye disorders and drug therapy.
38.2 Glaucoma is one of the leading causes of blindness.
38.3 Glaucoma therapy focuses on adjusting the circulation of aqueous humor.
38.4 Antiglaucoma medications may increase the outflow of aqueous humor.
38.5 Antiglaucoma medications may decrease the formation of aqueous humor.
38.6 Drugs provide relief for minor eye conditions and are used for eye exams.
38.7 Otic preparations treat infections, inflammation, and earwax buildup.
Drug Snapshot
The following drugs are discussed in this chapter:
Drug Classes
Prototype Drugs
DRUGS FOR GLAUCOMA
Drugs that increase the outflow of aqueous humor
***latanoprost (Xalatan)
Drugs that decrease the formation of aqueous humor
*** timolol (Betimol, Timoptic, others)
DRUGS FOR EYE EXAMINATIONS AND MINOR EYE CONDITIONS
DRUGS FOR EAR CONDITIONS
Learning Outcomes
After reading this chapter, the student should be able to:
1. Describe important anatomy relevant to disorders of the eyeball.
2. Identify the major risk factors associated with closed-angle glaucoma and open-angle glaucoma, and explain how increased intraocular pressure may cause blindness.
3. Explain the two major mechanisms by which drugs reduce intraocular pressure.
4. Identify important drugs that increase the outflow of aqueous humor and discuss primary actions and possible adverse effects.
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5. Identify important drugs that decrease the formation of aqueous humor and discuss primary actions and possible adverse effects.
6. Identify examples of drugs that dilate or constrict pupils, relax ciliary muscles, constrict ocular blood vessels, or moisten eye membranes.
7. Identify examples of drugs that treat conditions of the ear.
Key Terms
closed-angle glaucoma (glaw-KOH-mah)
cycloplegia (sy-kloh-PLEE-jee-ah)
cycloplegic drugs (sy-kloh-PLEE-jik)
external otitis (oh-TYE-tiss)
glaucoma (glaw-CO-muh)
mastoiditis (mass-toy-DYE-tuss)
miosis (my-OH-sis)
mydriasis (mih-DRY-uh-siss)
mydriatic drugs (mih DRY-atik)
open-angle glaucoma (glaw-KOH-mah)
otitis media (oh-TYE-tuss MEE-dee-ah)
tonometry (toh-NAHM-uh-tree)
The senses of vision and hearing provide the primary means for us to communicate with the world around us. Disorders affecting the eye and ear can result in problems with self-care, mobility, safety, and communication. The eye is vulnerable to a variety of conditions, many of which can be prevented, controlled, or reversed with proper pharmacotherapy. The first part of this chapter covers drugs used for the treatment of glaucoma and those used routinely by ophthalmic healthcare providers. The remaining part of the chapter presents drugs used for treatment of common ear disorders, including infections, inflammation, and the buildup of earwax.
Core Concept 38.1***
Knowledge of basic eye anatomy is essential for an understanding of eye disorders and drug therapy.
To understand eye disorders and drug action, a firm knowledge of basic ocular anatomy is required. As shown in Figure 38.1, the anterior segment is found at the front of the eyeball. It contains a watery fluid called aqueous humor. The anterior segment has two divisions: the anterior chamber and the posterior chamber. In the posterior chamber (Figure 38.2), aqueous humor originates from an important muscle structure called the ciliary body.
FIGURE 38.1 Internal structures of the eye.
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FIGURE 38.2 Forms of primary adult glaucoma: (a) In chronic, open-angle glaucoma, the anterior chamber angle remains open, but drainage of aqueous humor through the canal of Schlemm is impaired; (b) in acute, narrow closed-angle glaucoma, the angle of the iris and anterior chamber is smaller, obstructing the outflow of aqueous humor.
(a) Open-angle glaucoma: slowly rising intraocular pressure
(b) Closed-angle glaucoma: rapidly rising intraocular pressure
From there, it flows through the pupil and into the anterior chamber. Within the anterior chamber and around the periphery is a network of spongy connective tissue called trabecular meshwork. Connected to the trabecular meshwork is an opening called the canal of Schlemm, where aqueous humor drains from the anterior chamber.
GLAUCOMA
Glaucoma is an eye disorder that is characterized by gradual changes in peripheral vision, possibly advancing to blindness. In some cases, glaucoma is genetic; in other cases, glaucoma may be caused by eye trauma or disease. Some medications may contribute to the development of glaucoma, including long-term use of topical corticosteroids, some antihypertensives, antihistamines, and antidepressants. The major risk factors associated with the development of glaucoma include high blood pressure, migraine headaches, high levels of nearsightedness or farsightedness, and older age.
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Fast Facts Glaucoma
* More than 3 million Americans have glaucoma. More than 120,000 have developed blindness due to this disorder.
* Individuals of African heritage are affected more by glaucoma than any other ethnic group.
* Glaucoma is most common in people older than 60 years of age.
* Acute glaucoma is often caused by head trauma, cataracts, tumors, or hemorrhage.
* Chronic simple glaucoma accounts for 90% of all glaucoma cases.
[sidebar]
trabecular = strut-like
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tono = pressure
metry = measurement
intra = inside
ocular = eye
miotic = constricting pupil
Core Concept 38.2*** Glaucoma is one of the leading causes of blindness.
The presence of glaucoma may be detected by tonometry, an ophthalmic technique for measuring increased pressure inside the eye. Other routine refractory and visual field tests may uncover glaucoma signs. One problem with diagnosis is that patients with glaucoma typically do not experience symptoms and, therefore, do not seek medical attention. In some cases, glaucoma occurs so gradually that symptoms do not appear until late in the disease process
Glaucoma is characterized by increased pressure inside the eyeball, termed intraocular pressure
(IOP). The reason why IOP develops is because the normal flow of aqueous humor in the eye becomes blocked. Over time, pressure around the optic nerve can build, leading to blindness. In some cases, eye injury from the elevated IOP may be sudden, but in most cases it is gradual.
As shown in Figure 38.2, the two principal types of glaucoma are closed-angle glaucoma and open-angle glaucoma. Both disorders result from the same problem: Pressure inside the eyeball leads to progressive damage of the optic nerve. The differences between these two disorders include how quickly the IOP develops.
Open-angle, or chronic simple glaucoma, is the most common type, accounting for more than 90% of all cases. With this disorder, IOP develops more slowly. It is called “open angle” because the iris does not cover the trabecular meshwork (Figure 38.2a). If discovered early, open-angle glaucoma can be treated successfully with medications.
Closed-angle glaucoma, sometimes referred to as acute glaucoma, is usually caused by stress, impact injury, or medications. Pressure inside the anterior chamber increases suddenly because the iris is pushed over the area where the aqueous fluid normally drains (Figure 38.2b). Symptoms include intense headaches, difficulty concentrating, bloodshot eyes, and blurred vision. Closed-angle glaucoma requires immediate intervention (usually surgical).
Glaucoma therapy focuses on adjusting the circulation Core Concept 38.3*** of aqueous humor.
Treatment for glaucoma focuses on reducing the amount of aqueous humor formed or unblocking its drainage. Complete blockage of flow, as may occur with acute glaucoma, is a medical emergency that requires surgery to return the iris to its original position. For chronic glaucoma, drug therapy is employed to either increase the outflow of aqueous humor (canal of Schlemm location) or decrease the formation of aqueous humor (ciliary body location).
CONCEPT REVIEW 38.1
* Which components of the eye are specifically affected by glaucoma? Why is glaucoma such a dreaded eye disease? Drug therapy for glaucoma centers around which major approach?
Core Concept 38.4***
Antiglaucoma medications may increase the outflow of aqueous humor.
Drugs increasing the outflow of aqueous humor include miotics, sympathomimetics, and prostaglandins. All of these drugs are available as ophthalmic solutions. These drugs are summarized in Table 38.1.
Although antiglaucoma drugs are not designed to directly alter pupil diameter, they often produce this effect because of their physiologic properties. Cholinergic direct- and indirect-acting drugs cause constriction of pupils or miosis. Sympathomimetics are drugs that activate the sympathetic nervous system and cause dilation of pupils or mydriasis (see Chapter 9). Prostaglandins do not affect pupil diameter, but instead they directly dilate trabecular meshwork within the anterior chamber of the eye.
Prostaglandins
Prostaglandins are the preferred drugs for glaucoma therapy because they have long durations of action and produce fewer side effects than drugs from other classes. In resistant cases, they may be combined with drugs from other classes.
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Table 38.1 Antiglaucoma Drugs That Increase the Outflow of Aqueous Humor
Drug
Route and Adult Dose
Remarks
DIRECT- AND INDIRECT-ACTING CHOLINERGICS (MIOTIC DRUGS)
carbachol (Miostat)
One or two drops 0.75-3% solution in the lower conjunctival sac every 4 hours tid
Cholinergic drug; less useful in glaucoma than other drugs; causes stinging of the eyes
echothiophate (Phospholine Iodide)
One drop of 0.03% solution bid
Irreversible acetylcholinesterase inhibitor; use cautiously due to an intense and persistent miosis and ciliary-muscle contraction that may occur
pilocarpine (Isopto Carpine, Pilopine)
Acute glaucoma: One drop 1-2% solution for 3-6 doses Chronic glaucoma: One drop 0.5-4% solution bid
Cholinergic drug
NONSELECTIVE SYMPATHOMIMETICS (MYDRIATIC DRUGS)
dipivefrin HCl (Propine)
One drop 0.1 % solution bid
Converted to epinephrine in the eye
PROSTAGLANDINS
bimatoprost (Lumigan)
One drop 0.03% solution daily in the evening
Should not be used concurrently with latanaprost
***latanoprost (Xalatan)
One drop (1.5 mg) solution daily in the evening
May increase brown pigment in the iris
tafluprost (Zioptan)
One drop of 0.0015% solution in the evening
May increase brown pigment in the iris
travoprost (Travatan)
One drop 0.004% solution daily in the evening
Maximum effect after about 12 hours
Drugs in this class increase aqueous humor outflow by reducing congestion in trabecular meshwork. Their main side effect is a change in pigmentation, usually a change to a brown iris color in patients with lighter colored eyes. These medications cause cycloplegia (blurred vision), local irritation, and stinging of the eyes. Because of these effects, prostaglandins are normally administered just before the patient goes to bed. Although prostaglandins can be irritating to the eyes, they usually do not prevent the patient from falling asleep.
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Prototype Drug: *** Latanoprost (Xalatan)
Therapeutic Class: Antiglaucoma drug Pharmacologic Class: Prostaglandin, reducer of IOP
Actions and Uses: Latanoprost is a prostaglandin analog believed to reduce IOP by increasing the outflow of aqueous humor. The recommended dose is one drop in the affected eye(s) in the evening. It is metabolized to its active form in the cornea, reaching its peak effect in about 12 hours. It is used to treat open-angle glaucoma and elevated IOP.
Adverse Effects and Interactions: Adverse effects include ocular symptoms such as conjunctival edema, tearing, dryness, burning, pain, irritation, Itching, sensation of a foreign body in the eye, photophobia, and visual disturbances. The eyelashes on the treated eye may grow, thicken, and darken. Changes may occur in pigmentation of the iris of the treated eye and in the periocular skin. The most common systemic adverse effect is a flu-like upper respiratory infection. Rash, asthenia, or headache may occur.
Latanoprost interacts with thimerosal: If mixed with eyedrops containing thimerosal, precipitation may occur.
Direct- and Indirect-Acting Cholinergics (Miotic Drugs)
Carbachol (Miostat) and pilocarpine (Isopto Carpine, Pilopine HS) directly activate the cholinergic receptors, producing various responses in the eye, including dilation of trabecular meshwork, so that the canal of Schlemm can absorb more aqueous humor. When more aqueous humor is absorbed, IOP is reduced. Adverse effects include temporary cycloplegia. Cholinergic drugs are generally used in patients with open-angle glaucoma who have not responded to other medications. Echothiophate iodide (Phospholine iodide) is an indirect-acting cholinergic drug. It produces the same effects as direct-acting drugs, except that it blocks cholines-terase, the enzyme responsible for breaking down the natural neurotransmitter acetylcholine.
Nonselective Sympathomimetics (Mydriatic Drugs)
Dipivefrin (Propine) is a sympathomimetic drug. Dipivefrin is converted to epinephrine; epinephrine produces mydriasis, increased outflow of aqueous humor, and the subsequent fall of IOP. As discussed in Chapter 21, when epinephrine is released into the general circulation, it increases blood pressure and heart rate. Because of the potential for systemic adverse effects, this drug is rarely prescribed for the treatment of glaucoma.
[sidebar]
cyclop = round eye
plegia = paralysis
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Core Concept 38.5***
Antiglaucoma medications may decrease the formation of aqueous humor.
Although prostaglandins are preferred drugs for glaucoma, other medications may be needed to bring IOP to normal levels. Beta-adrenergic blockers, alpha2-adrenergic drugs, carbonic-anhydrase inhibitors, and osmotic diuretics are drug classes that decrease the formation of aqueous humor. These are summarized in Table 38.2.
Table 38.2 Antiglaucoma Drugs That Decrease the Formation of Aqueous Humor
Drug
Route and Adult Dose
Remarks
BETA-ADRENERGIC BLOCKERS
betaxolol (Betoptic)
One drop 0.5% ophthalmic solution bid
Beta,-blocker; reduces blood pressure, heart rate
Carteolol (Ocupress)
One drop 1 % ophthalmic solution bid
Nonspecific beta blocker; causes bronchoconstriction
levobunolol (Betagan)
One or two drops 0.25-0.5% ophthalmic solution once or twice daily
Nonspecific beta blocker
metipranolol (OptiPranolol)
One drop 0.3% ophthalmic solution bid
Nonspecific beta blocker
***timolol (Betimol, Timoptic, others)
One or two drops of 0.25-0.5% ophthalmic solution bid; gel (salve): apply daily
Nonspecific beta blocker
ALPHA2-ADRENERGIC DRUGS
apraclonidine (lopldine)
One drop 0.5% ophthalmic solution bid
Should not be used within 14 days of monoamine oxidase inhibitor (MAOI) administration
brimonidine tartrate (Alphagan)
One drop 0.2% ophthalmic solution tid
Should not be used within 14 days of MAOI administration
CARBONIC ANHYDRASE INHIBITORS
acetazolamide (Diamox)
PO: 250 mg one to four times per day
Oral diuretic; sulfonamide; also for seizures, high altitude sickness, and renal impairment
brinzolamide (Azopt)
One drop 1 % ophthalmic solution tid
Sulfonamide
dorzolamide (Trusopt)
One drop 2% ophthalmic solution tid
Sulfonamide
methazolamide (Neptazane)
PO: 50-100 mg bid or tid
Oral sulfonamide; less diuretic activity than acetazolamide
OSMOTIC DIURETICS
isosorbide (Ismotic)
PO: 1-3 g/kg bid-qid
Used before and after eye surgery
mannitol (Osmitrol)
IV: 1.5-2 mg/kg as a 15-25% solution over 30-60 minutes
Raises osmotic pressure, causing diuresis; IV medication
Beta-Adrenergic Blockers
Beta-blocking drugs include betaxolol (Betoptic), Carteolol (Ocupress), levobunolol (Betagan), metipranolol (OptiPranolol), and timolol (Betimol, Timoptic, others). The exact mechanism by which these drugs produce their effects is not fully understood. However, they all reduce IOP effectively without the ocular adverse effects of other autonomic drugs. Beta blockers do not alter pupil diameter or produce cycloplegic effects. The doses of ophthalmic beta block generally not high enough to enter the general circulation. Systemic adverse effects, if they occur, include bronchoconstriction, bradycardia, and hypotension.
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Prototype Drug: ***Timolol (Betimol, Timoptic, Others)
Therapeutic Class: Antiglaucoma drug Pharmacologic Class: Beta-adrenergic blocker, reducer of IOP, ocular hypotensive drug
Actions and Uses: Timolol is a nonselective beta-adrenergic blocker available as a 0.25% or 0.5% ophthalmic solution. Timolol reduces elevated IOP in chronic open-angle glaucoma by reducing the formation of aqueous humor. The usual dose is one drop in the affected eye(s) twice a day. Timoptic XE allows for once-a-day dosing. Treatment may require 2 to 4 weeks for maximum therapeutic effect. It is also available in tablets, which are prescribed to treat mild hypertension.
Cosopt PF is a solution of timolol with dorzolamide, a carbonic-anhydrase inhibitor. Combigan combines timolol with brimonidine, an alpha adrenergic agonist.
Adverse Effects and Interactions: The most common adverse effects are local burning and stinging on instillation. In most patients there is no significant systemic absorption to cause adverse effects as long as timolol Is applied correctly. If significant systemic absorption occurs, however, drug interactions could occur. Anticholinergics, nitrates, reserpine, methyldopa, or verapamil use could lead to hypotension and bradycardia. In-domethacin and thyroid hormone use could lead to decreased antihypertensive effects of timolol. Epinephrine use could lead to hypertension followed by severe bradycardia. Theophylline use could lead to decreased bronchodilation.
[sidebar]
hypo = reduced
tensive = tension
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Alpha2-Adrenergic Drugs
Alpha2-adrenergic drugs are less frequently prescribed than the other antiglaucoma medications. These medications include apraclonidine (Iopidine) and brimonidine (Alphagan). The most significant adverse effects are headache, drowsiness, dry mucosal membranes, blurred vision, and irritated eyelids.
Carbonic Anhydrase Inhibitors
Carbonic anhydrase inhibitors may be administered topically or by mouth (PO) to reduce IOP. Usually these medications are used as a second choice if beta blockers are not effective. Examples include acetazolamide (Diamox), brinzolamide (Azopt), dorzolamide (Trusopt), and methazolamide (Neptazane). These medications are more effective in cases of open-angle glaucoma. Patients must be cautioned when taking these medications because they are sulfonamides –drugs that may cause an allergic reaction. All of these drugs are diuretics, which means they can reduce IOP rather quickly and dramatically, altering serum electrolytes with continuous treatment.
Osmotic Diuretics
Osmotic diuretics are used in cases of eye surgery or acute closed-angle glaucoma. Examples include isosorbide (Ismotic) and mannitol (Osmitrol). Because they have an ability to reduce plasma volume very quickly (see Chapter 19), they may produce unpleasant adverse effects, including headache, tremors, dizziness, dry mouth, fluid and electrolyte imbalance, and thrombophlebitis (venous clot formation) near the site of IV administration.
CONCEPT REVIEW 38.2
* Describe two major approaches for controlling IOP in patients with glaucoma. What major drug classes are used in each case?
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New Drug Focus GLAUCOMA, RHO KINASE (ROCK) INHIBITORS, AND ADENOSINE AGONISTS
Two new drug classes are showing promise in the area of antiglaucoma drug research. Rho kinase (ROCK) inhibitors and adenosine agonists are drugs that target the anterior chamber of the eyeball. ROCK inhibitors relax trabecular meshwork cells and contract inner cells of the canal of Schlemm. They work by uncoupling actin from myosin, two proteins important for ciliary muscle contraction, and they shrink cells that block the outflow of aqueous humor. Adenosine agonists enhance extracellular matrix turnover in the trabecular meshwork, essentially achieving the same effect as ROCK inhibitors, increasing the outflow of aqueous humor. One unpleasant side effect for both drug classes is hyperemia (red eyes). Researchers are exploring different ways to address this unpleasant side effect.
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Nursing Process Focus Patients Receiving Pharmacotherapy for Glaucoma
ASSESSMENT
POTENTIAL NURSING DIAGNOSES*
Prior to drug administration:
* Obtain a complete health history, including cardiovascular, respiratory, thyroid, and renal conditions; eye trauma or infection; allergies; drug history; and possible drug interactions.
* Acquire the results of physical examination focusing on vital signs, visual acuity, visual fields (peripheral and central), presence of halos, blurred vision, and ocular pain.
* Self-Care Deficit related to impaired vision
* Acute Pain related to disease process or adverse drug effects
* Deficient Knowledge related to a lack of information about drug therapy
* Risk for Injury related to visual acuity deficits or adverse drug effects
(Continued)
[sidebar]
thrombo = clot
phleb = vein
itis = inflammation
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Nursing Process Focus [continued)
PLANNING: PATIENT GOALS AND EXPECTED OUTCOMES
The patient will:
* Experience therapeutic effects (normal eye pressure and no progression of visual impairment).
* Be free from or experience minimal adverse effects from drug therapy.
* Verbalize understanding of the drug’s use, adverse effects, and required precautions.
IMPLEMENTATION
Interventions and (Rationales)
Patient Education/Discharge Planning
*Administer ophthalmic solutions correctly and evaluate patient’s knowledge of correct administration. (Using proper technique ensures that medication stays within the eye and helps to prevent complications.).
*Instruct the patient In the proper administration of eyedrops to:* Remove contact lenses prior to administering eyedrops and wait 15 minutes before reinsertion.
*Wash hands prior to eyedrop administration.
Avoid touching the tip of the container to the eye, which may contaminate the solution.
*Administer the eyedrop in the conjunctival sac.
*Apply pressure over the lacrimal sac for 1 minute to decrease systemic absorption.
*Wait 5 minutes before administering other ophthalmic solutions.
*Schedule glaucoma medications around daily routines such as waking, mealtimes, and bedtime to lessen the chance of missed doses.
*Monitor visual acuity, blurred vision, pupillary reactions, extraocular movements, and ocular pain. (Periodic monitor-ing helps to determine the effectiveness of drug therapy.)
*Instruct the patient to report to the healthcare provider any changes in vision, eye pain, light sensitivity, halos around lights, or headache.
*Monitor the patient for specific contraindications for the prescribed drug. (There are many physiologic conditions for which ophthalmic solutions may be contraindicated.)
*Instruct the patient to inform the healthcare provider of all health-related problems and prescribed and over-the-counter (QTC) medications.
*Provide for eye comfort such as an adequately lighted room. (Ophthalmic drugs such as beta blockers used in the treatment of glaucoma can cause miosis and difficulty seeing in low-level lighting.)
*Caution the patient about driving or other activities in low-lighting conditions or at night until the effects of the drug are known.
*Monitor for conjunctivitis and lid reactions. (These may indicate adverse reactions to the drug or infection due to improper administration.)
*Review with the patient the correct medication administration technique.
*Instruct the patient to report itching, drainage, edema, ocular pain, sensation of a foreign body in the eye, photophobia, and visual disturbances to the healthcare provider.
*Monitor the color of the iris and periorbital tissue of the treated eye. (Prostaglandins can change the color of the Iris over time.)
*Inform the patient that: More brown color may appear in the iris and in the periorbital tissue of the treated eye only. Any pigmentation changes develop over months to years.
*Monitor vital signs periodically for systemic absorption of ophthalmic preparations. (Systemic ophthalmic drugs such as beta blockers and cholinergic drugs may cause serious cardiovascular complications such as hyperten-sion or bradycardia.)
*Instruct the patient to: Take and record vital signs weekly. Immediately report palpitations, chest pain, shortness of breath, and irregularities in pulse and blood pressure to the healthcare provider.
*Monitor and adjust environmental lighting to aid in patient’s comfort. (People who have glaucoma are sensitive to excessive light, especially extreme sunlight.)
*Instruct the patient to:
*Adjust environmental lighting as needed to enhance vision or reduce ocular pain.
*Wear darkened glasses as needed.
*Encourage compliance with the treatment regimen. (Noncompliance may result in total loss of vision.)
Instruct the patient:
*To comply with the medication schedule for eyedrop administration
*About the importance of regular follow-up care with the ophthalmologist.
*That IOP readings should be done prior to beginning treatment and periodically during treatment.
EVALUATION OF OUTCOME CRITERIA
Evaluate the effectiveness of drug therapy by confirming that patient goals and expected outcomes have been met (see “Planning”). See Tafotes 38.1 and 38.2 for lists of drugs to which these nursing actions apply.
*Herdman, T.H. & Kamitsuru, S. (Eds.). Nursing Diagnoses: Definitions & Classification 2015-2017. Copyright © 2014. 1994-2014 NANDA International. Used by arrangement by John Wiley & Sons, Inc. Companion website: www.wiley.com/go/nursingdiagnoses.
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EYE EXAMINATIONS AND MINOR EYE CONDITIONS *** Core Concept 38.6
Drugs provide relief for minor eye conditions and are used for eye exams.
Drugs for minor eye irritation and injury come from a broad range of classes, including antimicrobials, local anesthetics, corticosteroids, and nonsteroidal anti-inflammatory drugs (NSAIDs). A range of drug preparations may be used, including drops, salves, optical inserts, and injectable formulations. Some drugs only provide moisture to the eye’s surface. For example, bepo-tastine (Bepreve) is an antihistamine approved for twice daily dosing for itching associated with allergic conjunctivitis. Other drugs penetrate and affect a specific area of the eye.
Some drugs are specifically designed for ophthalmic examinations. These include cycloplegic drugs to relax ciliary muscles and mydriatic drugs to dilate the pupils. Caution must be used when administering anticholinergic mydriatics because these drugs can increase IOP and worsen glaucoma. In addition, anticholinergic drugs have the potential for producing adverse effects of the central nervous system such as confusion, unsteadiness, or drowsiness in adults. These effects are especially prevalent in older adults. Children generally become restless and spastic. Examples of cycloplegic, mydriatic, lubricant, and corneal edema drugs are listed in Table 38.3.
CONCEPT REVIEW 38.3
* List examples of commonly used drugs for minor eye irritation and injury. What are the major actions of cycloplegic and mydriatic drugs?
Table 38.3 Drugs for Eye Examinations and for Moistening Eye Membranes
Drug
Route and Adult Dose
Remarks
MYDRIATICS: SYMPATHOMIMETICS
phenylephrine (Neo-Synephrine) (see the Prototype Drug Box in Core Concept 9.8)
One drop 2.5% or 10% solution before eye exam
Decongestant and vasoconstriction properties; smaller doses provide temporary relief of eye redness; also for pupil dilation in closed-angle glaucoma
CYCLOPLEGICS: ANTICHOLINERGICS
atropine (Atro-Pen) (see the Prototype Drug Box in Core Concept 9.7)
One drop 0.5% solution daily
Also provided as ointment; should not be administered to patients with glaucoma; effects may be prolonged
cyclopentolate (Cyclogyl, Pentalair)
One drop 0.5-2% solution 40-50 minutes before procedure
Not for patients with glaucoma; causes burning and irritation; possible central adverse effects with higher doses
homatropine (Isopto Homatropine, others)
One or two drops 2% or 5% solution before eye exam
Not for patients with glaucoma; effects may be prolonged after treatment
scopolamine hydrobromide (Isopto Hyoscine)
One or two drops 0.25% solution 1 hour before eye exam
Not for patients with glaucoma; effects may be prolonged after treatment; possible central adverse effects with higher doses
tropicamide (Mydriacyl, Troplcacyl)
One or two drops 0.5-1 % solution before eye exam
Not for patients with glaucoma; central adverse effects with higher doses
LUBRICANTS CAUSING VASOCONSTRICTION
naphazoline (Albalon, Allerest, ClearEyes, others)
One to three drops 0.1 % solution every 3-4 hours prn
OTC and prescription medications available
oxymetazoline (OcuClear, Visine LR)
One or two drops 0.025% solution qid
OTC and prescription medications available
tetrahydrozoline (Murine Plus, Visine, others)
One or two drops 0.05% solution bid –tid
Primarily OTC medication
GENERAL PURPOSE LUBRICANTS
lanolin alcohol (Lacri-lube)
Apply a thin film to the inside of the eyelid
Mixed with mineral oil and petroleum jelly as a salve
polyvinyl alcohol (Liquifilm, others)
One or two drops prn
Artificial tear solution
DRUGS FOR CORNEAL EDEMA AND ITCHING
sodium chloride hypertonicity ointment (Muro 128 5% Ointment)
Apply a thin film to the inside of the eyelid; instill one drop into the affected eye(s) bid
Ophthalmic ointment for corneal edema; mixed with lanolin, mineral oil, purified water, and white petrolatum as a salve; for itching associated with allergic conjunctivitis
[sidebar]
mydriatic = dilating pupil
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externa = outside
ot = ear
itis = inflammation
media = middle
interna = inside
EAR CONDITIONS
The ear has two major sensory functions: hearing and maintenance of equilibrium and balance. Three important structural areas –the external ear, middle ear, and inner ear –carry out these functions (Figure 38.3).
Otitis, inflammation of the ear, most often occurs in the external and middle ear compartments. External otitis or otitis externa, commonly referred to as swimmer’s ear, is inflammation of the external ear; otitis media is inflammation of the middle ear. External ear infections most often occur with water exposure. Middle ear infections most often occur with upper respiratory infections, allergies, or auditory tube irritation. Of all ear infections, the most difficult ones to treat are infections of the inner ear (otitis interna). Mastoiditis, or inflammation of the mastoid sinus, can be a serious problem because if left untreated, it can result in hearing loss.
Core Concept 38.7***
Otic preparations treat infections, inflammation, and earwax buildup.
Combination drugs effectively treat many different types of ear conditions, including infections, earaches, edema, and earwax.
The basic treatment for ear infection is essentially the same as in all places of the body: antibiotics. Topical antibiotics in the form of eardrops may be administered for external ear infections. Ciprofloxacin (Cipro HC otic, Cetraxal) is a very common topical antibiotic used for ear infections. Adverse reactions can occur with this medication. These include rashes; white patches in the mouth; vaginal itching or discharge; and itching, pain, or mild irritation within the ear.
Systemic antibiotics (see Chapter 27) may be needed in cases in which external ear infections are extensive or in cases of middle or inner ear infections. Medications for pain, edema, and itching may also be necessary. Corticosteroids are often combined with antibiotics or with other drugs when inflammation is present. Examples of these drugs are listed in Table 38.4.
FIGURE 38.3 Structure of the external ear, middle ear and inner ear.
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Table 38.4 Otic Preparations
Drug
Route and Adult Dose
Remarks
acetic acid and hydrocortisone (Vosol HC)
Three to five drops in the affected ear every 4-6 hours for 24 hours, then five drops tid-qid
Combination of acetic acid and glucocorticoid; for general ear infections and inflammation
benzocaine and antipyrine (Auralgan)
Fill the ear canal with solution tid for 2-3 days
For acute otitis media and the removal of earwax; reduces earache associated with the infection
carbamide peroxide (Debrox)
One to five drops 6.5% solution bid for 4 days
To soften, loosen, and remove excessive earwax; OTC medication
ciprofloxacin and dexamethasone (Cipro Dex)
Four drops of the suspension instilled into the affected ear bid for 7 days
Combination of fluoroquinolone antibiotic and corticosteroid; for ear infections and inflammation
ciprofloxacin and hydrocortisone (Cipro HC)
Three drops of the suspension instilled into the affected ear bid for 7 days
Combination of fluoroquinolone antibiotic and corticosteroid; for ear infections and inflammation
polymyxin B, neomycin, and hydrocortisone (Cortisporin)
Four drops in the ear tid-qid
Combination of antibiotics and glucocorticoid; for general ear or mastoid infections and inflammation; some patients may develop dermatitis as a result of sensitivity to neomycin
Mineral oil, earwax softeners, and commercial products are also used for proper ear health. When earwax accumulates, it narrows the ear canal and may interfere with hearing. This is especially true for older patients who are not able to properly groom themselves. Healthcare providers working with younger and older patients are trained to take appropriate measures when removing impacted earwax.
CONCEPT REVIEW 38.4
* Identify the areas of the ear where microbial infections are most likely to occur. What kind of otic preparations treat infections, inflammation, and earwax buildup?
[box]
Patients Need to Know
Patients taking medications for eye and ear disorders need to know the following:
Regarding Eye Medications
1. Have regular eye exams after the age of 40.
2. Do not strain or lift heavy objects if risk for glaucoma is present. Any effort that might produce eyestrain should be avoided.
3. Make sure that all allergies or sensitivities, including those to sulfa drugs, are known to the healthcare providers.
4. Do not take OTC medications that are formulated to decrease redness of the eye for longer than 24 hours. Use eye lubricants instead. Persistent irritation should be reported immediately.
5. Keep eye solutions clear and sterile; do not actually touch the eye when instilling drops.
Regarding Ear Medications
6. Take precautions to keep the ear canal dry when in or around water for an extensive time. Use appropriate earplugs or a bathing cap.
7. Apply 2% acetic acid to the ear canal after swimming. Acetic acid acts as a drying agent and restores the ear canal to its normal acidic condition.
8. Antibiotics (with or without steroids) may be needed to treat swimmer’s ear. Consult a healthcare provider.
9. Do not place objects such as cotton swabs in the ear canal; use a bulb syringe approved for removing debris and warm water. Use any cerumen dissolving agent responsibly.
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Chapter Review Core Concepts Summary
38.1 Knowledge of basic eye anatomy is essential for an understanding of eye disorders and drug therapy.
The anterior chamber of the eye is the place where aqueous humor is circulated. Aqueous humor originates from the ciliary body located in the posterior chamber and drains into the canal of Schlemm found in the anterior chamber.
38.2 Glaucoma is one of the leading causes of blindness.
Glaucoma develops because the flow of aqueous humor in the anterior eye chamber becomes disrupted, leading to increasing intraocular pressure (IOP). Two principal types of glaucoma are closed-angle glaucoma and open-angle glaucoma.
38.3 Glaucoma therapy focuses on adjusting the circulation of aqueous humor.
Glaucoma therapy generally works by increasing the outflow of aqueous humor or decreasing aqueous humor formation.
38.4 Antiglaucoma medications may increase the outflow of aqueous humor.
Drugs that increase the outflow of aqueous humor include miotics, sympathomimetics, prostaglandins, and prostamides. Prostaglandins are the preferred class of drugs for glaucoma treatment.
38.5 Antiglaucoma medications may decrease the formation of aqueous humor.
Medications that decrease the formation of aqueous humor include beta blockers, alpha2-adrenergic drugs, carbonic-anhydrase inhibitors, and osmotic diuretics.
38.6 Drugs provide relief for minor eye conditions and are used for eye exams.
Mydriatic or pupil-dilating drugs and cyclopegic or ciliary-muscle relaxing drugs are routinely used for eye examinations. Some drugs constrict local blood vessels. Others lubricate the eyes.
38.7 Otic preparations treat infections, inflammation, and earwax buildup.
Combination drugs provide relief of conditions associated with the external, middle, and inner ear. Drugs include antibiotics, corticosteroids, and earwax dissolving drugs.
REVIEW Questions
Answer the following questions to assess your knowledge of the chapter material, and go back and review any material that is not clear to you.
1. A patient is at the Optometrie office for an eye examination. She is told that the healthcare provider will have to dilate her pupils with_eyedrops so he can see the back of the eye.
1. Miotic
2. Mydriatic
3. Constricting
4. Corticosteroids
2. In a plan of care, a patient is to receive a drug that relieves pressure in the eye by increasing the outflow of aqueous humor. This drug would be:
1. Timolol (Timoptic).
2. Betaxolol (Betoptic).
3. Pilocarpine (Ocusert).
4. Ciprofloxacin (Cipro).
3. The patient is informed that the medication used to relieve the pressure in her eye by decreasing production of aqueous humor is:
1. Timolol (Timoptic).
2. Atropine sulfate.
3. Pilocarpine (Ocusert).
4. Ciprofloxacin (Cipro).
4. The patient has been given a prescription for acetazolamide (Diamox) 250 mg PO every 4 hours. What is the total amount of Diamox the patient will take in a 24-hour period?
1. 250 mg
2. 500 mg
3. 750 mg
4. 1000 mg
5. A patient has an ear infection and is taking Cipro. If he also had inflammation, which of the following class of drug would be added?
1. Corticosteroids
2. Aluminum sulfate and calcium acetate (Domeboro)
3. Osmotic diuretics
4. Carbonic-anhydrase inhibitors
6. Prior to administering eardrops, the nurse should inform the patient that:
1. The solution should stay in the ear for 1 hour.
2. The solution will be removed within 1 hour.
3. There may be a decrease in hearing for a few minutes.
4. The medication will take effect immediately.
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7. A patient has just been prescribed ciprofloxacin for an ear infection. The nurse tells her that the drug can cause adverse reactions. The symptoms can include: (Select all that apply.)
1. Rash.
2. White patches in the mouth.
3. Pain within the ear.
4. Total loss of hearing.
5. Vaginal itching.
8. In the plan of care for patients with glaucoma, the rationale for giving anti-glaucoma medications would be to reduce the pressure within the eye by:
1. Decreasing aqueous humor production and increasing outflow of aqueous humor.
2. Increasing aqueous humor production and decreasing outflow of aqueous humor.
3. Decreasing aqueous humor production and decreasing outflow of aqueous humor.
4. Increasing aqueous humor production and increasing outflow of aqueous humor.
9. The patient started on travoprost (Travatan) is instructed that:
1. This medication is administered in the morning only.
2. Due to pupil constriction, visual acuity may be affected.
3. This medication may change the pigmentation of the iris.
4. Due to dilation of the pupils, visual acuity may be affected.
10. If the patient is allergic to sulfonamides, the nurse understands that he should not take:
1. Methazolamide (Neptazane).
2. Betaxolol (Betoptic).
3. Carteolol (Ocupress).
4. Beta blockers.
CASE STUDY Questions
[Image: Ms. Mary Saunders.]
Remember Ms. Saunders, the patient introduced at the beginning of the chapter? Now read the remainder of the case study. Based on the information you have learned in this chapter, answer the questions that follow.
Ms. Mary Saunders is a 65-year-old African American woman presenting with severe pain in the right eye, headache, and blurred vision. She has a history of primary hypertension and glaucoma. Her blood pressure is 140/90 mmHg. No other obvious signs are noted. In the course of the examination, she mentions that she has recently relocated. It has been a particularly stressful time because she has not had much help from her family. She has not been using her antiglaucoma medication, the beta blocker timolol (Timoptic).
1. The nurse and Ms. Saunders begin to discuss the importance of using the glaucoma medication. The nurse explains that if left untreated pharmacologically, glaucoma could lead to:
1. Mydriasis.
2. Cycloplegia.
3. Blindness.
4. Vertigo.
2. Ms. Saunders states she knows that she should be applying her medication but has some concerns. She asks the nurse if timolol can cause any problems. The nurse responds that the most common adverse effect of timolol (Timoptic) is:
1. Burning and stinging.
2. Sinus irritation.
3. Bronchoconstriction.
4. Edema around the eyes.
3. In addition to the discussion about adverse effects, the nurse tells Ms. Saunders that it is not advisable to take the following drugs with timolol (Timoptic): (Select all that apply.)
1. Epinephrine.
2. Ciprofloxacin.
3. Nitrates.
4. Corticosteroids.
4. Ms. Saunders wants to know how long it would be before she could tell if the medication was working. The nurse tells her it would take about:
1. 1 week.
2. Up to 2 weeks.
3. 2 to 4 weeks.
4. 1 to 2 months.
Answers and complete rationales for the Review and Case Study Questions appear in Appendix A.
REFERENCE
Herdman, T. EL, & Kamitsuru, S. (Eds.). (2014). NANDA International nursing diagnoses: Definitions and classification, 2015-2017. Oxford, United Kingdom: Wiley-Blackwell
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SELECTED BIBLIOGRAPHY
American Association for Pediatric Ophthamology and Strabismus, (n.d.). Dilating eye drops. Retrieved from http://www.aapos.org/ terms/conditions/43
Gemenetzi, M., Yang, Y., & Lotery, A. J. (2012). Current concepts on primary open-angle glaucoma genetics: A contribution to disease pathophysiology and future treatment. Eye, 26, 355-369. doi:10.1038/eye.2011.309
Glaucoma Research Foundation. (2015). Glaucoma facts and stats. Retrieved from http://www.glaucoma.org/glaucoma/glaucoma-facts-and-stats.php
Karmel, M. (n.d). Glaucoma pipeline drugs: Targeting the trabecular mesh-work. Retrieved from http://www.aao.org/eyenet/article/ glaucoma-pipeline-drugs-targeting-trabecular-meshw
Lieberthal, A. S., Carroll, A. E., Chonmaitree, T., Ganiats, T. G., Hober-man, A., Jackson, M. A.,… Tunkel, D. E. (2013). The diagnosis and management of acute otitis media. Pediatrics, 232(3), e964-e999. doi:10.1542/peds.2012-3488
Newman-Casey, P. A., Weizer, J. S., Heisler, M., Lee, P. P., & Stein, J. D. (2013). Systematic review of educational interventions to improve glaucoma medication adherence. Seminars in Ophthalmology 28, 191-201. doi:10.3109/08820538.2013.771198
Saxby, C, Williams, R., & Hickey, S. (2013). Finding the most effective cerumenolytic. The Journal of Laryngology & Otology, 127, 1067-1070. doi.10.1017/S0022215113002375
Tehrani, S. (2015). Gender difference in the pathophysiology and treatment of glaucoma. Current Eye Research, 40,191-200. doi:10.31 09/02713683.2014.968935
Venekamp, R. P., Sanders, S., Glasziou, P. P., Del Mar, C. B., & Rovers, M. M. (2013). Antibiotics for acute otitis media in children. Cochrane Database of Systematic Reviews, 1, Art. No.: CD000219. doi:10.1002/14651858.CD000219.pub3
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Appendix A
Complete Answers and Rationales to Review and Case Study Questions
Chapter 1 Review Answers
1. Answer: 4. Core Concept: 1.1. Rationale: Pathophysiology is the study (ology) of the nature (physio) of disease (patho). This includes how disease changes the function of the body. Pharmacology is defined by how drugs enter and travel through the body (option 1). Pharmacotherapy is defined by how drugs improve the health of the human body (option 2). Option 3 describes drug actions. Cognitive Level: Understanding. Client Need: N/A. Nursing Process: N/A.
2. Answer: 3. Core Concept: 1.3. Rationale: Biologies are naturally occurring agents produced in animal cells, in microorganisms, or by the body itself. Herbs, natural extracts, vitamins, and minerals are a part of natural therapies (option 1). Traditional drugs are chemically produced or synthesized in a laboratory (option 2). Biologies are widely used in drug therapy (option 4). Cognitive Level: Understanding. Client Need: N/A. Nursing Process: N/A.
3. Answer: 1. Core Concept: 1.2. Rationale: LPNs and LVNs cannot prescribe medication. The scope of practice for LPN and LVNs includes educating patients about their medications (option 2), ensuring drug laws are upheld (option 3), and assisting patients with medication management (option 4). Cognitive Level: Understanding. Client Need: Safe and Effective Care. Nursing Process: Implementation.
4. Answers: 1,2, and 4. Core Concept: 1.4. Rationale: Patients should know that self-treatment with OTC drugs can be ineffective, that OTC drugs can react with foods, prescriptions, or other OTC drugs, and that they can cause serious adverse effects. In addition, patients should know that it is important to read and follow instructions. Option 3 is incorrect because the potential for further injury or disease is a consideration even when taking OTC medications. Option 5 is incorrect because a medication that works well for some people (friends) may not work for the patient. Cognitive Level: Understanding. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Planning.
5. Answer: 2. Core Concept: 1.5. Rationale: Pharmaceutics is the science of preparing and dispensing of medications. Pharmacology is the study of medicine (option 1). Therapeutics is the branch of medicine concerned with disease prevention and treatment (option 3). Healthcare includes all the activity included in maintaining or restoring health (option 4). Cognitive Level: Remembering. Client Need: N/A. Nursing Process: N/A.
6. Answer: 2. Core Concept: 1.6. Rationale: The Food, Drug, and Cosmetic Act was the first law preventing the marketing of drugs that had not been thoroughly tested before they were marketed. Although the Pure Food and Drug Act of 1906 (option 1), the Prescription Drug User Fee Act of 1992 (option 3), and the FDA Modernization Act of 1997 (option 4) made significant contributions to the safety and availability of medications, the focus of these acts was different. Cognitive Level: Remembering. Client Need: N/A. Nursing Process: N/A.
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7. Answer: 2. Core Concept: 1.8. Rationale: The clinical investigation stage of the drug approval process is the longest because it takes place in three different phases and involves the testing (research) of medications using humans with certain diseases. Drugs are evaluated for drug dosages, effectiveness, safety within certain populations, and adverse effects. The results of research must be presented to the FDA before the drug is allowed to proceed to the next stage. The preclinical stage involves basic scientific research (option 1). The NDA submission and review follows the clinical investigation stage and is not the longest (option 3). Postmarketing studies continue to monitor drug effects and are not typically the longest stage (option 4). Cognitive Level: Remembering. Client Need: N/A. Nursing Process: N/A.
8. Answer: 4. Core Concept: 1.9. Rationale: The Prescription Drug User Fee Act (1992) allowed the FDA to obtain extra income, which enabled it to hire more personnel in order to handle a greater number of drug applications more efficiently. This action resulted in cutting application review times by half. The Pure Food and Drug Act of 1906 (option 1), the Sherley Amendment (option 2), and the Public Health Service Act (option 3) did not affect application review time. Cognitive Level: Remembering. Client Need: N/A. Nursing Process: N/A.
9. Answer: 4. Core Concept: 1.7. Rationale: Part of the FDA Modernization Act (1997) included closer monitoring of drugs for death or serious injury. As a result of the monitoring, warnings were placed within a “black box” on drug packaging inserts. Black box warnings are not used to provide general information (option 1). The warnings do not list the ingredients in a medication (option 2) nor are they located on the drug container label (option 3). Black Box warnings are located on drug package inserts. Cognitive Level: Remembering. Client Need: N/A. Nursing Process: N/A.
10. Answers: 1-3. Core Concept: 1.10. Rationale: Each of the following options has been identified as a serious agent used in bioterrorist threats: anthrax, incapacitating chemicals, and radiation. The viruses that cause the common cold and sexually transmitted infections are not considered agents used in bioterrorist threats (options 4 and 5). Cognitive Level: Remembering. Client Need: N/A. Nursing Process: N/A.
Chapter 2 Review Answers
1. Answer: 1. Core Concept: 2.1. Rationale: Therapeutic drug classification focuses on what a drug does clinically. Pharmacologic drug classification (option 2) focuses on a drug’s mechanism of action, and the term chemical focuses on the actual composition of a drug (option 3). Therefore, option 4 is incorrect because there is only 1 correct answer. Cognitive Level: Remembering. Client Need: N/A. Nursing Process: N/A.
2. Answer: 2. Core Concept: 2.1. Rationale: Mechanism of action refers to how specific medications affect the body. Therapeutic usefulness (option 1) describes the usefulness of a medication in treating a condition. Clinical focus (option 4) describes the use of drugs in a clinical setting. How a medication produces its effects on the body is its mechanism of action, not a model for other drugs (option 3). Cognitive Level: Remembering. Client Need: N/A. Nursing Process: N/A.
3. Answer: 4. Core Concept: 2.2. Rationale: Drugs are only given one name for both the chemical and generic drug categories; therefore, options 1 and 2 are incorrect because they list only one of these. Option 3 is incorrect because a drug may have many trade names, depending on the number of manufacturers. Cognitive Level: Remembering. Client Need: N/A. Nursing Process: N/A.
4. Answer: 4. Core Concept: 2.2. Rationale: The drug trade name is given by the drug developer, which has ownership (propriety) of the particular drug. Chemical drug names (option 1) are difficult to remember but are always considered in pharmacotherapy and
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are used in part in some drug names. Option 2, matching an active ingredient with a trade name drug, is challenging because of the increasing number of combination drugs on the market. Option 3 is incorrect because trade names are usually capitalized and generic names are written in lower case. Cognitive Level: Remembering. Client Need: N/A. Nursing Process: N/A.
5. Answer: 4. Core Concept: 2.3. Rationale: The inert ingredients in a trade name drug and its generic form can differ. This difference can affect bioavailability, affecting the drug’s reaction in the body. Drug formulations for trade name drugs are not always the same as their generic equivalents (option 1). In fact, ingredients may be more tightly compressed either in trade name drugs or in generic drugs, making option 2 incorrect. Option 3 is incorrect because generic drugs are not always best for treatment, despite their lower costs. Cognitive Level: Understanding. Client Need: N/A. Nursing Process: N/A.
6. Answer: 1, 3, 4, 5. Core Concept: 2.3. Rationale: It is important that the nurse understands that generic drugs cannot be substituted for drugs on the negative formulary list because of concern over the bioavailability of generic drugs and possible adverse effects on patient outcomes (option 1). The trade name drug must be dispensed as written on the prescription (option 3). The list was formed because of concern over the bioavailability of generic drugs and possible adverse effects on patient outcomes (Option 4). However, the efforts of consumer advocacy groups have led to changes in the lists (option 5). Option 2 is incorrect because the use of and drugs included on negative formulary lists are not consistent throughout the United States. Cognitive Level: Understanding. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Data Collection.
7. Answer: 2. Core Concept: 2.4. Rationale: Physical dependence is the result of repeated use of a drug leading to physical changes and adaptations within the nervous system. When the drug is no longer available, the individual experiences physical signs of discomfort. Addiction (option 1) is the overwhelming feeling that drives someone to use a drug. Psychological dependence (option 3) is the intense emotional desire for continued drug use. Withdrawal (option 4) refers to the physical and psychological signs and symptoms a person experiences when the drug is no longer taken or available. Cognitive Level: Remembering. Client Need: N/A. Nursing Process: N/A.
8. Answer: 2. Core Concept: 2.4. Rationale: The Controlled Substance Act restricted the use of drugs that have significant potential for abuse. This law did not introduce drugs into the marketplace (option 1), restrict the use of all drugs that have abuse potential (option 3), or allow patients to obtain refills for Schedule II drugs without a visit to their healthcare provider (option 4). Cognitive Level: Remembering. Client Need: N/A. Nursing Process: N/A.
9. Answer: 3. Core Concept: 2.4. Rationale: Schedule IV drugs (option 3) have a relatively lower abuse and dependency potential than Schedules II and III drugs (options 1 and 2). Whereas Schedule IV drugs always require a prescription, some Schedule V drugs (option 4) do not require a prescription. Cognitive Level: N/A. Client Need: N/A. Nursing Process: N/A.
10. Answer: 3. Core Concept: 2.5. Rationale: A pregnant woman may take drugs classified within pregnancy category A or B. They have been shown to be relatively safe. Drugs within all other categories have been shown to have some adverse effect on the fetus, especially category X drugs (option 1), which have been shown to have a significant risk to both the woman and the fetus. Drugs in category D (option 4) may cause harm but can be provided if the benefit of the drug outweighs the risks. All medications, including herbs or dietary substances (option 2), must be reported to the healthcare provider because some of them can have adverse effects on the fetus. Cognitive Level: Remembering. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Planning.
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Chapter 3 Review Answers
1. Answer: 3. Core Concept: 3.7. Rationale: The stethoscope, large syringe, and water are all needed to administer medication by way of the nasogastric route. These pieces of equipment are not needed to administer medication through the transdermal (skin) route (option 1), the IV route (option 2), or the rectal route (option 4). Cognitive Level: Understanding. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Implementation.
2. Answer: 2. Core Concept: 3.7. Rationale: Crushing XR medications alters the way they are delivered to and absorbed by the body. XR medications are not necessarily distasteful when crushed (option 1). When taken orally, crushing these medications should not cause obstructions (option 3). Some oral medications that are not XR can be crushed without affecting bioavailability (option 4). Cognitive Level: Understanding. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Planning.
3. Answer: 1. Core Concept: 3.9. Rationale: Aspiration of the syringe is a safety technique done while giving an IM injection to ensure that the needle is in the muscle and not in a blood vessel (option 1). Aspiration (option 2) should not produce an air pocket and is not used to avoid hitting a nerve (option 3) or to remove air from the syringe (option 4). Cognitive Level: Understanding. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Implementation.
4. Answer: 3. Core Concept: 3.9. Rationale: Administering medication via the IV route is the fastest way for it to reach the target tissue and begin working (onset) because the medication is injected directly into the circulatory system. Administering medications through the transdermal (option 1), IM (option 2), and ophthalmic (option 4) routes allows for the onset of the medication at different rates but not faster than being directly administered into the circulatory system. Cognitive Level: Remembering. Client Need: N/A. Nursing Process: N/A.
5. Answer: 1. Core Concept: 3.4. Rationale: The term STAT means immediately. Single (option 2), prn (option 3), and standing orders (option 4) do not indicate that an order needs to be done immediately. Cognitive Level: Application. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Implementation.
6. Answer: 1. Core Concept: 3.2. Rationale: In this case, the nurse is checking for information found on the label –the right medication (option 1). The right documentation (option 2), patient (option 3), and time of delivery (option 4) are all parts of the six rights of drug administration but they are not involved in checking the medication label. Cognitive Level: Application. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Implementation.
7. Answer: 5. Core Concept: 3.1. Rationale: Nurses should know and understand the medication they give (option 1), including its intended use (option 2), how the patient’s age or disease state may affect the drug’s pharmacotherapeutic response (option 3), and any side or adverse effects it may cause (option 4). Therefore, option 5 is the correct answer. Cognitive Level: Understanding. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Data Collection.
8. Answer: 4. Core Concept: 3.4. Rationale: The information on the MAR does not include the actual classification of the medication(s) ordered. It does includes the date the medication is to be administered (option 1), the route of administration (option 2), and the dose to be administered (option 3). Cognitive Level: Knowledge. Client Need: N/A. Nursing Process: N/A.
9. Answer: 4. Core Concept: 3.5. Rationale: This is a conversion question between the metric system and the household system: 4-5 mL equals 1 teaspoon (option 4). Options 1, 2, and 3 are not equal to 5 mL. Cognitive Level: Application. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Implementation.
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10. Answer: 3. Concept: 3.8. Rationale: It is sometimes desirable for topical drugs (such as nitrates) to be absorbed into the systemic system. A local effect of a topical medication requires that it stay within the area of application (option 1). The type of medication applied to the skin comes in the form of creams, lotions, gels, powders, and sprays (option 4). Therefore, nurses should always wear gloves when preparing and administering the medication to prevent accidental absorption into their skin (option 2). Cognitive Level: Remembering. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: N/A.
Chapter 4 Review Answers
1. Answer: 3. Core Concept: 4.4. Rationale: The liver is the primary organ involved in metabolism. Patients with advanced liver disease usually need to receive lower doses than normal because their liver is unable to metabolize drugs to their inactive forms. The liver is not usually involved in the absorption (option 1), distribution (option 2), or excretion (option 4) of drugs. Cognitive Level: Understanding. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Planning.
2. Answer: 2. Core Concept: 4.6. Rationale: The drug is to be given twice a day because of its half-life. This is done to maintain a therapeutic level of medication to the target cells. Option 1 is incorrect because taking the drug only once a day may not be enough to maintain therapeutic levels. The nurse should know about this mechanism of action to be able to answer the patient’s question (option 3). Even though the initial dose of the drug may not be enough to maintain a therapeutic level over a period of time, it is still effective for a short time, and therefore is not blocked (option 4). Cognitive Level: Applying. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Implementation.
3. Answers: 3 and 4. Core Concepts: 4.8 and 4.9. Rationale: Some medications act as antagonists, binding to receptors and producing responses that block agonists. Other medications act as agonists, binding to receptors and causing a cellular response that usually results in a therapeutic action. Drug effectiveness is determined by the desired outcome. It is possible that a drug could be more effective at a lower dose than another drug used for the same purpose (option 1). Efficacy refers to the ability of a drug to produce a more intense response as its concentration is increased. It is not solely reliant on drug dosing but on the drug’s ability to meet the intended outcome (options 2 and 5). Cognitive Level: Analyzing. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Planning.
4. Answer: 3. Core Concept: 4.8. Rationale: Agonists bind with a receptor to produce a therapeutic response. Antagonists (option 1) or blockers (option 4) bind to receptors, producing responses to block agonists. The term facilitate (option 2) is used to describe the action of agonists; such agonists are facilitators of cellular action. Level: Remembering. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Planning.
5. Answer: 2. Core Concept: 4.2. Rationale: The presence of food in the digestive tract slows the absorption of any drugs taken orally. The presence of food does not cause drugs to be absorbed more rapidly (option 1), or to become either neutralized or activated by gastric enzymes (options 3 and 4). Cognitive Level: Understanding. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Evaluation.
6. Answers: 1, 2, 3, and 5. Core Concept: 4.7. Rationale: Drug interactions can occur when two or more drugs are taken within a specific time frame of each other or when certain drugs are taken with specific foods (options 1 and 2). The route of administration greatly influences the rate of drug absorption –that is, IV drugs act more quickly because they
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are placed directly into the bloodstream and bypass the necessity for absorption across the GI tract (option 3). Diseases of the liver or kidney impact drug effectiveness because of their role in the breakdown and excretion of medications (option 5). As long as the patient takes the medication as ordered by their healthcare provider, time of day has little impact on drug effectiveness (option 4). Cognitive Level: Analyzing. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Planning.
7. Answer: 2. Core Concept: 4.3. Rationale: Only fat-soluble substances will pass the blood-brain barrier. Option 1 is incorrect because some antibiotics can easily cross the blood-brain barrier. Half-life of the drug is not determined by its ability to cross the blood-brain barrier (option 3). Antibiotics are usually absorbed easily from the GI tract (option 4). Cognitive Level: Understanding. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Planning.
8. Answer: 3. Core Concept: 4.4. Rationale: The first-pass effect occurs when the liver metabolizes the drug to a less active form before it is distributed to the rest of the body and target organs. In some cases, this effect can inactivate more than 90% of an orally administered drug before it can reach the general circulation. Option 1 is incorrect because half-life is the length of time required for a drug’s concentration in the plasma to decrease by one half. Potency refers to a drug’s strength at a certain concentration or dose (option 2). The rate of elimination is defined as the amount of drug removed from the body by normal physiologic processes within a period of time (option 4). Cognitive Level: Remembering. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Data Collection.
9. Answers: 1, 2, and 4. Core Concept: 4.5. Rationale: Drugs are removed from the body mainly by the kidneys, but also by bile or glandular activity, and the respiratory tract. Sweat glands are less effective at excreting drugs than other organs (option 3), and drugs are not usually excreted through the skin (option 5). Cognitive Level: Applying. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Implementation.
10. Answer: 3. Core Concept: 4.5, Lifespan and Diversity. Rationale: Metabolic enzyme activity is reduced in older patients, making them more sensitive to medications than other patients. Drug doses for this age group are often reduced to compensate for the differences in metabolic rates. Drug dosages are not increased (option 1). Increasing (option 2) or decreasing (option 4) the number of times an older patient takes their medication does not directly affect metabolism. Cognitive Level: Analyzing. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Planning.
Chapter 5 Review Answers
1. Answer: 1. Core Concept: 5.1. Rationale: During assessment/data collection; the nurse collects data about the patient prior to implementation of medication administration. Option 2 (planning), option 3 (implementing), and option 4 (evaluating) are incorrect because the nurse is collecting information. Cognitive Level: Applying. Client Need: Health Promotion and Maintenance. Nursing Process: Data Collection.
2. Answer: 3. Core Concept: 5.4. Rationale: During the implementation phase, it is the nurse’s responsibility to both administer medication correctly and teach patients about medications they are taking. Option 1 is incorrect because it describes more general nursing actions not related to medication. Option 2 includes evaluating, which is another step of the nursing process. Option 4 describes the evaluation step. Cognitive Level: Understanding. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Implementation.
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3. Answer: 2. Core Concept: 5.5. Rationale: The main goal of administering a drug is to achieve a therapeutic effect, such as to relieve a symptom or cure a disease, with no or minimal adverse effects. Therefore, acquiring evidence of a drug’s therapeutic effects is the most important role of the nurse in the evaluation phase of the nursing process. Patient satisfaction (option 1), minor adverse drug effects (option 3), and the possibility of noncompliance (option 4) are not as important as the therapeutic effect of the drug. Cognitive Level: Understanding. Client Need: Physiological Integrity/Pharmacological Therapies. Nursing Process: Evaluation.
4. Answer: 1,3,4, and 5. Core Concept: 5.1. Rationale: Before administering a medication, it is the nurse’s responsibility to collect data about: drug allergies (option 1) to avoid giving the patient a drug that causes adverse effects; history of renal or hepatic disease (option 3) because these organs are involved in the excretion and metabolism of drugs; and the patient’s physical examination information (option 4), in order to determine if they have any conditions that might contraindícate the administration of a specific drug. In addition, if administering an oral medication, the patient’s ability to swallow properly must be determined (option 5). Option 2 is not applicable during the data collection phase because the drug had not yet been given. Cognitive Level: Understanding. Client Need: Health Promotion and Maintenance. Nursing Process: Data Collection.
5. Answer: 3. Core Concept: 5.4. Rationale: Implementation; the nurse is putting the plan of care into action by preparing and giving the patient ordered medication. Option 1 (data collection) would occur before planning and implementation. Option 2 (planning) would occur before implementation. Option 4 (evaluation) would occur after administering the drug. Cognitive Level: Applying. Client Need: Physiological Integrity/ Pharmacological Therapies. Nursing Process: Implementation.
6. Answer: 3. Core Concept: 5.2. Rationale: The second phase of the nursing process, nursing diagnosis, involves the analysis of data, identification of a patient’s response to health problems, and the formulation of diagnostic statements such as Activity Intolerance. Option 1 (data collection) is done prior to diagnosing. Option 2 (implementation) is performing the nursing actions. Option 4 (planning) occurs after the nursing diagnoses have been identified. Cognitive Level: Understanding. Client Need: Health Promotion and Maintenance. Nursing Process: Nursing Diagnosis.
7. Answer: 4. Core Concept: Introduction. Rationale: The nursing process is a systematic approach to problem solving that is used to determine the benefits and risks of the use of medications. Option 1 is a limited assessment, not the nursing process. Option 2 describes documentation, not the nursing process. Option 3 is incorrect because the nursing process is not limited to textbook knowledge. Cognitive Level: Understanding. Client Need: Safe and Effective Care Environment/Coordinated Care. Nursing Process: All phases.
8. Answer: 3. Core Concept: Introduction. Rationale: The scope of practice for LPNs and LVNs is to contribute to each phase of the nursing process under the direction of the RN. Option 1 is incorrect because the LPN or LVN always works under the direction of the RN. Option 2 is incorrect because the LPN or LVN works with the RN, not the healthcare provider on the plan of care. Option 4 is incorrect because the LPN or LVN collaborates with the RN and is not completely dependent. Cognitive Level: Understanding. Client Need: Safe and Effective Care. Nursing Process: All phases.
9. Answer: 2. Core Concept: 5.3. Rationale: In the planning phase, the team lays out the necessary teaching and actions that will need to be performed. Option 1 is incorrect because the nurse is planning, not collecting data. Option 3 is incorrect because the nurse is not yet implementing the plan of care. Option 4 is incorrect because the nurse has not performed actions that need to be evaluated. Cognitive Level: Applying. Client Need: Safe and Effective Care Environment/Coordinated Care. Nursing Process: Planning.
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10. Answer: 2. Core Concept: 5.2. Rationale: Etiology means the “cause” of an identified problem, in this case, anxiety. When formulating a problem statement, the nursing diagnosis (or problem) is followed by the etiology (cause) after the words “related to.” Option 1 (insomnia) is the nursing diagnosis, not the etiology. Option 3 (difficulty falling asleep) is a manifestation of insomnia. Option 4 (difficulty staying asleep) is evidence of insomnia. Cognitive Level: Understanding. Client Need: Health Promotion and Maintenance. Nursing Process: Nursing Diagnosis.
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