Tr-I-LIfe

diuretics

General Use

Thiazide diuretics and loop diuretics are used alone or in combination in the treatment of hypertension or edema due to CHF or other causes. Potassium-sparing diuretics have weak diuretic and antihypertensive properties and are used mainly to conserve potassium in patients receiving thiazide or loop diuretics. Osmotic diuretics are often used in the management of cerebral edema.

General Action and Information

Enhance the selective excretion of various electrolytes and water by affecting renal mechanisms for tubular secretion and reabsorption. Groups commonly used are thiazide diuretics and thiazide-like diuretics (chlorothiazide, chlorthalidone, hydrochlorothiazide, indapamide, and metolazone), loop diuretics (bumetanide, furosemide, and torsemide), potassium-sparing diuretics (amiloride, spironolactone, and triamterene), and osmotic diuretics (mannitol). Mechanisms vary, depending on agent.

Contraindications

Hypersensitivity. Thiazide diuretics may exhibit cross-sensitivity with other sulfonamides.

Precautions

Use with caution in patients with renal or hepatic disease. Safety in pregnancy and lactation not established.

Interactions

Additive hypokalemia with corticosteroids, amphotericin B, piperacillin, or ticarcillin. Hypokalemia enhances digitalis glycoside toxicity. Potassium-losing diuretics decrease lithium excretion and may cause toxicity. Additive hypotension with other antihypertensives or nitrates. Potassium-sparing diuretics may cause hyperkalemia when used with potassium supplements or ACE inhibitors.

Assessment

• Assess fluid status throughout therapy. Monitor daily weight, intake and output ratios, amount and location of edema, lung sounds, skin turgor, and mucous membranes.

• Assess patient for anorexia, muscle weakness, numbness, tingling, paresthesia, confusion, and excessive thirst. Notify health care professional promptly if these signs of electrolyte imbalance occur.

• Hypertension: Monitor blood pressure and pulse before and during administration. Monitor frequency of prescription refills to determine compliance in patients treated for hypertension.

• Increased Intracranial Pressure: Monitor neurologic status and intracranial pressure readings in patients receiving osmotic diuretics to decrease cerebral edema.

• Increased Intraocular Pressure: Monitor for persistent or increased eye pain or decreased visual acuity.

• Lab Test Considerations: Monitor electrolytes (especially potassium), blood glucose, BUN, and serum uric acid levels before and periodically throughout course of therapy.

• Thiazide diuretics may cause increased serum cholesterol, low-density lipoprotein (LDL), and triglyceride