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Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Chapter 48
Drugs Affecting Corticosteroid Levels
Chapter 48
Drugs Affecting Corticosteroid Levels
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
QuestionQuestion
• Where are the adrenal glands located?
– A. Brain
– B. Pancreas
– C. Liver
– D. Kidneys
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Answer Answer
• D. Kidneys
• Rationale: The adrenal glands are located on top of the kidneys.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Physiology Physiology
• The hormones of the endocrine system are important messengers in the communication between cells.
• Two adrenal glands are located one at the top of each kidney. Each gland is composed of two distinct parts—the medulla and the cortex.
• The medulla and cortex are crucial to metabolism and fluid and electrolyte balances.
• The adrenal medulla synthesizes and secretes catecholamines.
• The adrenal cortex is involved primarily in the synthesis and secretion of glucocorticoids and mineralocorticoids.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
PathophysiologyPathophysiology
• There are two forms of adrenal insufficiency—primary and secondary.
• Primary adrenal insufficiency (Addison disease) results from the destruction of the adrenal cortex caused by infection or hemorrhage.
• In secondary adrenal insufficiency, the deficiency of cortisol secretion is secondary to insufficient secretion of ACTH by the anterior pituitary.
• Cushing syndrome is a rare disorder resulting from increased adrenocortical secretion of cortisol, resulting in chronic elevation in glucocorticoid and adrenal androgen hormones.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Glucocorticoids Glucocorticoids
• The primary endogenous glucocorticoids produced by the adrenal gland are cortisol (hydrocortisone) and cortisone.
• They have no role in any systemic anti-inflammatory therapeutic regimen because of their high mineralocorticoid activity relative to their anti-inflammatory activity.
• All natural and synthetic glucocorticoids act by binding to a specific cytoplasmic glucocorticoid receptor.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Glucocorticoids (cont.)Glucocorticoids (cont.)
• A common adverse effect of synthetic glucocorticoids administered in high doses for anti-inflammatory and immunosuppressant effects (combined or separately) is suppression of the HPA axis.
• Abrupt discontinuation of a glucocorticoid following prolonged administration may result in acute adrenal insufficiency.
• Prototype drug: prednisone (Deltasone, Prednicot)
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Prednisone: Core Drug Knowledge Prednisone: Core Drug Knowledge
• Pharmacotherapeutics
– Anti-inflammatory and immunosuppressive effects
• Pharmacokinetics
– Absorbed from GI tract. Metabolized: liver. Excreted: urine.
• Pharmacodynamics
– Primarily glucocorticoid activity, although some mineralocorticoid activity is present and more apparent when the drug is administered in high doses
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Prednisone: Core Drug Knowledge (cont.)Prednisone: Core Drug Knowledge (cont.)
• Contraindications and precautions
– Hypersensitivity and systemic fungal infections
• Adverse effects
– Anxiety, mood swings, insomnia, headache, GI complaints, menstrual irregularities, hyperglycemia
• Drug interactions
– Interactions with drugs and laboratory studies
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Prednisone: Core Patient Variables Prednisone: Core Patient Variables
• Health status
– Review history and medication use
• Life span and gender
– Pregnancy Category C drug
• Lifestyle, diet, and habits
– Assess the patient’s diet.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Prednisone: Nursing Diagnoses and Outcomes Prednisone: Nursing Diagnoses and Outcomes
• Excess Fluid Volume related to sodium and water retention secondary to corticosteroid therapy
– Desired outcome: The patient will relate causative factors and methods of preventing edema and exhibit decreased peripheral and sacral edema.
• Risk for Infection or Risk for Injury related to anti-inflammatory, immunosuppressive, dermatologic, and metabolic effects of chronic corticosteroid therapy
– Desired outcome: The patient will demonstrate knowledge of risk factors associated with potential for infection or injury and will practice appropriate precautions for prevention.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Prednisone: Nursing Diagnoses and Outcomes (cont.)Prednisone: Nursing Diagnoses and Outcomes (cont.)• Imbalanced nutrition: More than Body Requirements
related to increased appetite secondary to corticosteroid medications
– Desired outcome: The patient will maintain a healthy weight, discuss current nutritional needs, and discuss the effects of exercise on weight control.
• Altered Body Image related to cushingoid characteristics or physical changes secondary to glucocorticoid therapy
– Desired outcome: The patient will verbalize and demonstrate acceptance of appearance, verbalize and demonstrate healthy adaptation and coping skills.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Prednisone: Planning and InterventionsPrednisone: Planning and Interventions
• Maximizing therapeutic effects
– The most opportune time for administration of daily doses or alternate-day doses of glucocorticoids is early in the morning.
• Minimizing adverse effects
– Monitor the patient, especially the surgical patient, carefully for signs of infection.
– Administration can lead to peptic ulcer disease.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Prednisone: Teaching, Assessment, and EvaluationsPrednisone: Teaching, Assessment, and Evaluations
• Patient and family education
– Discuss taking the drug exactly as prescribed.
– Discuss not stopping the drug abruptly.
– Emphasize the importance of patients’ notifying all health care providers about glucocorticoid therapy.
• Ongoing assessment and evaluation
– Monitor for therapeutic drug response, adverse drug reactions, and indications of drug toxicity.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
QuestionQuestion
• Prednisone will increase the serum levels of K+ level.
– A. True
– B. False
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Answer Answer
• B. False
• Rationale: Serum levels of K+ may be decreased with the use of prednisone.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Mineralocorticoids Mineralocorticoids
• Aldosterone, the naturally occurring mineralocorticoid, is expensive and requires parenteral administration.
• This adrenal corticosteroid has both high mineralocorticoid and glucocorticoid activity (its glucocorticoid potency is 15 times greater than that of hydrocortisone).
• However, when used as replacement therapy in adrenocortical deficiency, its therapeutic effect is the mineralocorticoid activity.
• Prototype drug: fludrocortisone (Florinef Acetate)
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Fludrocortisone: Core Drug Knowledge Fludrocortisone: Core Drug Knowledge
• Pharmacotherapeutics
– Partial replacement therapy for primary adrenocortical insufficiency
• Pharmacokinetics
– Administered: oral. Peak: 1.7 hours. T½: 3.5 hours.
• Pharmacodynamics
– Acts on the distal renal tubule to enhance the reabsorption of sodium and to increase the urinary excretion of both potassium and hydrogen ions
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Fludrocortisone: Core Drug Knowledge (cont.)Fludrocortisone: Core Drug Knowledge (cont.)
• Contraindications and precautions
– Hypersensitivity and systemic fungal infections
• Adverse effects
– Small doses: marked sodium retention and increased urinary potassium excretion.
• Drug interactions
– Fludrocortisone interacts with many of the same drugs as prednisone because of its high glucocorticoid activity.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Fludrocortisone: Core Patient Variables Fludrocortisone: Core Patient Variables
• Health status
– Review medical history.
• Life span and gender
– Pregnancy Category C drug
• Lifestyle, diet, and habits
– Assess diet. The drug causes Na retention and K loss.
• Environment
– Assess the environment where the drug will be given.
• Culture and inherited traits
– Assess cultural and dietary practices.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Fludrocortisone: Nursing Diagnoses and Outcomes Fludrocortisone: Nursing Diagnoses and Outcomes
• Excess Fluid Volume related to mineralocorticoid-induced sodium and water retention
– Desired outcome: The patient will relate causative factors and methods of preventing fluid retention and exhibit decreased peripheral and sacral edema.
• Risk for Infection or Risk for Injury related to immunosuppressive effects of chronic corticosteroid therapy
– Desired outcome: The patient will demonstrate knowledge of risk factors associated with potential for infection and will practice appropriate precautions for prevention.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Fludrocortisone: Nursing Diagnoses and Outcomes (cont.)Fludrocortisone: Nursing Diagnoses and Outcomes (cont.)
• Risk for Injury related to adrenocortical insufficiency
– Desired outcome: The patient will demonstrate knowledge of risk factors associated with potential for injury and will practice appropriate precautions for prevention.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Fludrocortisone: Planning and InterventionsFludrocortisone: Planning and Interventions• Maximizing therapeutic effects
– Assess for drugs that may interact with and decrease its efficacy.
– Evaluate the need for an increased dose during times of injury, stress, infection, or surgery.
• Minimizing adverse effects
– Monitor blood pressure, fluid balance, and electrolyte status.
– Review the importance of following a diet high in potassium-rich foods.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Fludrocortisone: Teaching, Assessment, and EvaluationsFludrocortisone: Teaching, Assessment, and Evaluations
• Patient and family education
– Instruct patients to adhere to drug therapy as prescribed, stressing the importance of regular follow-up visits with the prescriber.
– Encourage patients to wear a medical identification bracelet stating their medical condition and their specific drug therapy.
• Ongoing assessment and evaluation
– Monitor for edema, weight gain, hypertension, cardiac arrhythmias, or muscular weakness.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
QuestionQuestion
• The patient is being discharged home on fludrocortisone. What would be important to teach the patient about diet?
– A. Limit salt and potassium intake
– B. Increase salt and potassium intake
– C. Limit salt intake and increase potassium intake
– D. Increase salt intake and limit potassium intake
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
AnswerAnswer
• C. Limit salt intake and increase potassium intake
• Rationale: Fludrocortisone causes sodium retention and potassium loss. Inform the patient of foods that are low in sodium or high in potassium.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Steroid Hormone Antagonists Steroid Hormone Antagonists
• Steroid hormone antagonists act to inhibit or suppress the adrenal cortex, thus controlling the symptoms of Cushing syndrome.
• Prototype drug: aminoglutethimide (Cytadren)
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Aminoglutethimide: Core Drug Knowledge Aminoglutethimide: Core Drug Knowledge
• Pharmacotherapeutics
– Used to treat hypercortisolism (Cushing syndrome)
• Pharmacokinetics
– Administered: oral. T½: 5 to 9 hours.
• Pharmacodynamics
– Inhibits enzymatic conversion of cholesterol to pregnenolone
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Aminoglutethimide: Core Drug Knowledge (cont.)Aminoglutethimide: Core Drug Knowledge (cont.)
• Contraindications and precautions
– Hypersensitivity
• Adverse effects
– Drowsiness, dizziness, skin rash, nausea, and anorexia
• Drug interactions
– Coumarin, warfarin, other oral anticoagulants, theophylline, digoxin, medroxyprogesterone, and dexamethasone
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Aminoglutethimide: Core Patient Variables Aminoglutethimide: Core Patient Variables
• Health status
– Assess CBC and thyroid levels.
• Life span and gender
– Pregnancy Category D drug
• Lifestyle, diet, and habits
– Assess daily activities.
• Environment
– Assess the environment where the drug will be given.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Aminoglutethimide: Nursing Diagnoses and Outcomes Aminoglutethimide: Nursing Diagnoses and Outcomes
• Risk for Injury related to CNS effects of hypotension and sedation, endocrine effects of hypothyroidism, or hematologic effects of agranulocytosis, leukopenia, and thrombocytopenia
– Desired outcome: The patient will remain injury-free during aminoglutethimide therapy.
• Imbalanced nutrition: Less than Body Requirements related to adverse effects of anorexia and nausea
– Desired outcome: There will be no change or an improved nutritional status.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Aminoglutethimide: Nursing Diagnoses and Outcomes (cont.)Aminoglutethimide: Nursing Diagnoses and Outcomes (cont.)
• Disturbed Body Image related to hirsutism and masculinization (in females)
– Desired outcome: The patient will identify and incorporate methods for camouflaging the adverse hormonal effects of aminoglutethimide therapy.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Aminoglutethimide: Planning and InterventionsAminoglutethimide: Planning and Interventions
• Maximizing therapeutic effects
– Advise the patient to carry medical identification and to inform health care professionals that this drug is being taken.
• Minimizing adverse effects
– Suppression of aldosterone production may cause orthostatic or persistent hypotension.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
Aminoglutethimide: Teaching, Assessment, and EvaluationsAminoglutethimide: Teaching, Assessment, and Evaluations
• Patient and family education
– Discuss the adverse reactions of aminoglutethimide, including dizziness or drowsiness, nausea, anorexia, headache, orthostatic hypotension, and hirsutism.
– Caution patients about driving or performing other tasks that requires alertness, coordination, or physical dexterity until the effects of the drug are known.
• Ongoing assessment and evaluation
– Continuously assess for adrenal insufficiency because adjustment of the aminoglutethimide dose may be necessary.
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
QuestionQuestion
• Aminoglutethimide is a Pregnancy Category ___ drug?
– A. A
– B. B
– C. C
– D. D
– E. X
Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins
AnswerAnswer
• D. D
• Rationale: Aminoglutethimide is a Pregnancy Category D drug.