Drugs that affect the Endocrine System

1. Drugs that affect the Endocrine System Pharmacology I

2. Objective 1: define the term hormone • Objective 2: list the endocrine glands • Objective 3: identify the hormones that are secreted by the anterior pituitary and describe their main functions in the body

3. Objective 4: identify the hormones that are released by the posterior pituitary and describe their main functions in the body

4. Objective 5: identify the two main thyroid hormones • Objective 6: describe how the body synthesizes the thyroid hormones

5. Objective 7: identify the actions of drugs used to treat hyperthyroidism

6. Objective 8: list the anti-thyroid agents used to treat hyperthyroidism • Drugs are: • Iodine-131 (131I) • Propylthiuracil (PTU, Propacil) • Methimazole (Tapazole

7. Radioactive iodine • Taken up by thyroid • Destroys hyperactive thyroid tissue • Essentially no other tissue is affected • Takes 3-6 months for fully assess effect • If more than one dose needed, three months between doses is needed

8. Dosing is oral • Add to water • No color • No taste • Be very careful not to spill (hazardous) • Client can not be pregnant

9. Side effects • Tenderness in thyroid gland • Hyperthyroidism in 40%, second dose needed • Hypothyroidism

10. Drug interactions • Lithium carbonate

11. PTU and Tapazole • Block synthesis of T3 and T4 • Takes days to 3 weeks to see effect • Can use long term • Can use short term pre subtotal thyroidectomy

12. Side effects • Purpuric, maculopapular rash • Headaches, salivary and lymph node enlargement • Bone marrow suppression • Hepatotoxicity • Nephrotoxicity

13. Objective 9: identify the hypothyroid conditions • Hypothyroid condition in adults called myxedema • Congenital hypothyroidism called cretinism

14. Objective 10: list the thyroid agents • Levothyroxine replaces T3 and T4

15. Liothyronine synthetic T3 • Onset of action more rapid than levothyroxine • Liotrix synthetic mixture levothyroxine and liothyronine (4 to 1 ratio) • Provides consistent levels of T3 and T4

16. Thyroid USP • From beef, pork, or sheep thyroid glands • Oldest form available, cheapest • Lacks purity, uniformity, stability

17. Side effects • Hyperthryoidism • Drug interactions • Warfarin: larger doses needed • Digitalis: smaller doses needed • Hyperglycemia can occur early in therapy

18. Objective 11: describe the nursing process associated with administering thyroid or anti-thyroid preparations

19. Assessment important • Clients sensitive to replacement therapy, monitor for adverse effects • Levothyroxine started low and dose increased over weeks

20. Safe handling, storage and disposal of radioactive materials via institution policy • Blood levels need to be monitored • Clients need to be alert to side effects and report • Clients need to report if no improvement

21. Objective 12: name the parts of the adrenal gland • Objective 13: list the types of hormones secreted by the adrenal glands

22. Two hormones from adrenal gland • Mineralcorticoids • Glucocorticoids

23. Mineralcorticoids • Maintain fluid and electrolyte balance • Used to treat adrenal insufficiency • Fludrocortisone (Florinef) • Aldosterone • Act on distal tubules, causes water and sodium retention • Causes excretion of potassium and hydrogen

24. Objective 14: describe the metabolic effects of the glucocorticoids, and the consequences of these effects

25. Objective 15: describe how glucocorticoids suppress inflammation • Corticosteroids secreted by adrenal cortex of adrenal gland Glucocorticoids

26. Glucocorticoids include • Cortisone, hydrocortisone, prednisone etc. • Have antiinflammatory, antiallergic activity

27. Also affect glucose, protein and fat metabolism • Glucocorticoids secreted in response to stressors • Cause release of epinephrine

28. Objective 16: identify therapeutic uses of glucocorticoids • Glucocorticoids used for replacement therapy when adrenal gland not functional • High doses used for inflammation, allergy, asthma

29. Use of corticosteroids • Used with caution in those with • Diabetes mellitus • Heart failure • Hypertension • Peptic ulcer • Mental disturbance • Suspected infection

30. After one week, discontinue drug slowly (wean off) • Abrupt discontinuation • Fever; Malaise; Fatigue • Weakness; orthostatic dizziness, hypotension • Dyspnea; hypoglycemia

31. Topical: apply as directed, may use occlusive dressing • Alternate –day therapy: give between 6 & 9 AM; give with meals

32. Side Effects • Electrolyte imbalance, fluid accumulation • Susceptibility to infection • Behavioral changes • Hyperglycemia • Peptic ulcer formation • Delayed wound healing

33. Drug interactions • Loop diuretics: can enhance electrolyte loss • Warfarin: can have increased or decreased effect • Hyperglycemia: diabetics and children need to be monitored

34. Objective 17: list the glucocorticoid preparations

35. Various drugs for topical, oral, injection, inhalation • Cortisone • Dexamethasone (Decadron, Dexone) • Fludrocortisone (Florinef)-also mineralcorticoid

36. Fluocinonide (Lidex) • Hydrocortisone (Cortef, Solu-Cortef) • Methlprednisolone (Solu-Medrol, Depo-Medrol) • Prednisolone (Delta-Cortef) • Prednisone (Deltasone, Apo-Prednisone) • Triamcinolone (Aristocort, Kenalog)

37. Objective 18: describe nursing care responsibilities associated with administering glucocorticoids

38. Objective 19: identify the functions of insulin in the body • Objective 20: define diabetes mellitus • Objective 21: identify the site of insulin production in the body • Objective 22: list the types of diabetes

39. Objective 23: explain the functions of insulin • Hormone from beta cells of the pancreas (islets of Langerhans) • Normally: 0.5 – 1 unit per hour secreted • Adult: 30-50 units per day • Insulin transports glucose into cells; helps metabolize protein and fat. • Diabetes is a metabolic disorder: all body systems affected

40. Objective 24: identify the onset, the peak, and the duration of action for rapid, intermediate, long acting and fixed combinations of insulin

41. Rapid-Acting Insulin • Lispro and Aspart • Most rapid acting of insulins • They are synthetic insulin analogs • Give within 10-15 minutes of a meal • Onset: 10 minutes • Peak: 30 to 60 min • Duration: 5 hours

42. Short-Acting Insulin • Regular insulin • Human regular insulin available, not just animal derivation • Give within 30-60 minutes of meals • Onset: 30 minutes • Peak: 2.5-5 hours • Duration: 5-10 hours • Administration: subcutaneous or IV

43. Intermediate-Acting Insulin • Neutral protamine Hagedorn (NPH) • Contains regular insulin and protamine • Protamine binds to insulin: slow release • Onset: 1-4 hours (pork is 1-1.5 hrs) • Peak: 8-12 hours (pork: 8-12 hrs) • Duration: 18-24 hours (pork: 24 hrs)

44. Lispro: can be mixed with protamine • Humalog mix 75/25 • 75% Lispro with protamine • 25% Lispro • Rapid acting insulin with intermediate duration of action (12-24 hours)

46. Long-Acting Insulin • Humulin Ultralente • Crystalline form of Lente insulin • Onset: 4-8 hours • Peak: 12-18 hours • Duration: 24-28 hours

47. Insulin-Glargine solution (Lantus) • Biosynthetic • Absorbed in a uniform manner-no large fluctuations of insulin levels = reduction in possible hypoglycemia Onset: 5 hours Peak: no pronounced peak activity Duration: 24 hours Do NOT mix with other insulins