Drugs that affect the Urinary System

1. Drugs that affect the Urinary System NURS 1950: Pharmacology

5. Diuretics work in the kidney at various sites of the nephron • Can interfere with the action of aldosterone causing loss of sodium • Where goes sodium, so goes water

8. What happens with diuretics • Decrease excess water • Loop diuretics + 0.9% NaCl = loss of calcium • Decrease excess NaCl • Decrease cerebral edema (Mannitol) • Decrease increased IOP (Diamox)

9. Mannitol is an osmotic diuretic (a sugar); • in the brain, its presence causes water to be drawn to it • Works the same way in the eye: • the excess intraocular fluid is drawn to the mannitol in the hyperosmotic plasma

10. Carbonic anhydrase inhibitor • Diamox very weak diuretic • Useful in treating glaucoma

11. Methylxanthines • Aminophylline • Theophylline • Caffeine • Theobromine • Diuretic effect from improved blood flow to kidney • Generally not used for diuretic effect

12. Obj. 9 Thiazides • Action of the thiazides • Act on the distal tubules of the kidney • Block reabsorption of sodium and chloride ions from the tubule • The unreabsorbed Na and Cl ions pass into the collecting ducts, taking water with them • Thiazides have antihypertensive properties because of direct vasodilation effect on peripheral arterioles • Expected outcomes from treatment • Decreased edema and improvement of symptoms RT excess fluid accumulation • Reduction in BP

13. Thiazides • Assessments • Mental status • Diabetics require baseline blood glucose • Assess hearing • Assess for symptoms of acute gout • SE to expect: orthostatic hypotension • Usually in initial stages of treatment • Teach client safety measures

14. Thiazides • SE to report • GI irritation, N/V, constipation • Electrolyte imbalance, dehydration • Hyperuricemia • Hyperglycemia • Hives, rash • Thiazides can interact with • Digoxin, corticosteroids • Lithium, NSAIDs • Oral hypoglycemic agents

15. Thiazides can interact with • Digoxin, corticosteroids • Lithium, NSAIDs • Oral hypoglycemic agents

16. Thiazide and Thiazide-like Drugs • Thiazide diuretics include • Bendroflumethiazide (Naturetin) • Chlorothiazide (Diuril) • Hydrochlorothiazide (HCTZ) {Esidrix, HydroDiuril} • Polythiazide (Renese) • Trichlomethiazide (Naqua, Metahydrin, Diurese)

17. Thiazide-like drugs include • Chlorthalidone (Hygroton) • Indapamide (Lozol) • Metolazone (Zaroxolyn)

18. Objective 8: describe the uses, actions, and adverse effects of the thiazide and thiazide-like diuretics • Drugs that affect the loop of Henle • Bumetanide (Bumex) • Ethacrynic acid (Edecrin) • Furosemide (Lasix) • Torsemide (Demadex)

19. Loop Diuretics • Act in the loop of Henle in the kidney • Inhibits Na and Cl reabsorption • Some increase blood flow to glomeruli • Inhibits electrolyte absorption in proximal tubule • Lose sodium, chloride, potassium, magnesium, sodium bicarbonate

20. Loop Diuretics • Onset of diuretic effect varies, but is within 1-2 hours. IV, drugs work within 5-10 minutes • Peak effect within 1-2 hours • Duration approximately 6 hours

21. Loop Diuretics • Maximum mg/day • Bumex 10 mg per 24 hours • Edecrin 400 mg per 24 hours • Lasix 1000 mg/24 hours • Cross sensitivities • Sulfonamides and Lasix, Demadex • SE to expect • Oral irritation • Dry mouth • Orthostatic hypotension

22. Loop Diuretics • SE to report with loop diuretics • GI irritation, abdominal pain • Electrolyte imbalance, dehydration • Hives, pruritus, rash • Some can cause loss of hearing and hyperglycemia (interfere with hypoglycemic agents)

23. Loop Diuretics • Drug interactions • Alcohol, barbiturates, narcotics • Aminoglycosides • Cisplatin • NSAIDs • Corticosteroids • Probenecid • Digoxin

24. Loop Diuretics • Loop diuretics include • Bumetanide (Bumex) • Ethacrynic acid (Edecrin) • Furosemide (Lasix) • Torsemide (Demadex)

25. Objective 11: list the electrolyte imbalance that most commonly occurs as a result of diuretic therapy • Why is there concern about the electrolyte balance?

26. Obj. 12 Potassium-Sparing Diuretics • Weak antihypertensives • Mechanism of action unknown • Do work in distal renal tubule • Retains potassium • Excretes sodium • Some have anti-aldosterone activity

27. Potassium Sparing diuretics • Maximum dosing per 24 hrs • drug dependent • SE to expect with Midamor: • anorexia, N/V, flatulence and HA • SE to report: • electrolyte imbalance, dehydration,

28. Potassium Sparing diuretics • SE to expect and report with Aldactone and Dyrenium: • mental confusion, HA, diarrhea, electrolyte imbalance, dehydration, gynecomastia, reduced libido, breast tenderness • Dyrenium can also cause allergic reaction (hives, pruritus, rash)

29. Potassium Sparing diuretics • Generally, drug interactions for the K+ sparing agents • Lithium, ACE inhibitors, salt substitutes, K+ replacement • NSAIDs, • Potassium-sparing drugs include • Amiloride (Midamor) • Spironolactone (Aldactone) • Triamterene (Dyrenium)

30. Potassium Sparing diuretics • Potassium-sparing drugs include • Amiloride (Midamor) • Spironolactone (Aldactone) • Triamterene (Dyrenium)

31. Objective 13: explain how increased fluid intake enhances the action of diuretics • Why is an adequate fluid intake important with diuretic therapy? • If the client has to get up during the night to void, what will they probably do?

32. Objective 14: list good dietary sources of potassium • What are some good dietary sources of potassium? • If a client is on Aldactone, what would you tell them about high potassium foods?

33. Obj. 15Nursing Implications: Diuretics • Assessments to make • Teaching to include:

34. Obj. 16 Drugs for UTI • Drugs include • Antibiotics • Fosfomycin (Monurol) • Quinolones : cinoxacin, nalidixic acid, norfloxacin • Methenamine madelate • Nitrofurantoin

35. Fosfomycin (Monurol) • Inhibits bacterial cell wall synthesis • Reduces adherence of bacteria to epithelial cells of urinary tract • Single dose therapy • SE to expect: • nausea, diarrhea, abdominal cramps, flatulence • SE to report: • perineal burning, dysuria • Indicates UTI is not responding to treatment • Drug interactions • Drugs such as metoclopramide that increase GI motility

36. Quinolones Norfloxacin (Noroxin) has wide range of activity against gram negative and gram positive bacteria • Expensive • Reserve for resistant/recurrent infections • SE to report • Hematuria as crystals can form in urinary tract • HA, tinnitus, dizziness, tingling sensations, photophobia • Various drug interactions can occur • Assess client’s current drug therapy, monograph of quinolone being used

37. Methenamine mandelate (Mandelamine) • Converts to ammonia and formaldehyde in acidic urine • Used in clients susceptible to chronic, recurrent UTIs • Preexisting infections treated with antibiotics • Implementation • DO NOT crush the tablets • pH testing of urine: report over 5.5 • SE to expect • N/V, belching • SE to report • Hives, pruritus, rash • Bladder irritation, dysuria, frequency • Drug interactions • Acetazolamide, sodium bicarbonate • Sulfamethizole

38. Nitrofurantoin (Furadantin, Macrodantin) • Interferes with several bacterial enzyme systems • Effective only in the urinary tract • SE to expect: • N/V, anorexia, urine discoloration • SE to report: • Dyspnea, chills, fever, erythematous rash, pruritus • Peripheral neuropathies • Second infection • Drug interactions • Magnesium containing products can decrease absorption

39. Obj. 17 Bladder Active Drugs • Bethanecole chloride (Urecholine) • Neostigmine (Prostigmin) • Oxybutynin chloride (Ditropan) • Phenazopyridine (Pyridium) • Tolterodine (Detrol)

40. Urecholine • Parasympathetic nerve stimulant • Causes contraction of detrusor urinae muscle • Results in urination • May also stimulate gastric motility • Can increase gastric tone • Can restore impaired rhythmic peristalsis • SE to expect • Flushing of skin, HA • SE to report • N/V, sweating, colicky pain, abdominal cramps • Diarrhea, belching, involuntary defecation

41. Neostigmine (Prostigmin) • Anticholinesterase agent • Binds to cholinesterase • Prevents destruction of acetylcholine • Effects are: miosis; increased tone of intestinal, skeletal, and bladder muscles • Bradycardia; stimulation of secretions of salivary and sweat glands • Constriction of bronchi and ureters • Neostigmine used to prevent and treat postoperative distension and urinary retention • Assess for pregnancy, intestinal or urinary obstruction, peritonitis • Assess coronary status

42. Oxybutynin (Ditropan) • Antispasmodic agent—acts directly on smooth muscle of the bladder • Delays initial urge to void • Do not use if glaucoma, myasthenia gravis, ulcerative colitis, obstructive uropathy • SE to expect • Dry mouth, urinary hesitance, retention • Constipation, bloating • Blurred vision • Report any SE that are intensified

43. Phenazopyridine (Pyridium) • Produces local anesthetic effect in urinary tract • Acts about 30 min. after administration • Used to relieve burning, pain, urgency, frequency in UTI • Reduces bladder spasms • SE to expect • Reddish-orange urine color • SE to report • Yellow sclera or skin

44. Tolterodine (Detrol) • Muscarinic receptor antagonists • Inhibit muscarinic action of acetylcholine on bladder smooth muscle • Used to treat overactive bladder • Do not use if glaucoma, ulcerative colitis, obstructive uropathy • S/E to expect • Dry mouth • Urinary hesitance, retention • Constipation, bloating • Blurred vision • Report if the effects intensified

45. Objective 18: Discuss patient education guidelines for drugs that affect the urinary system

46. Objective 19: identify at least one nursing diagnosis that may be applicable for clients receiving diuretic therapy under the guidance of the instructor