Diuretic Agents PDF

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Diuretic agents...

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Thiazide Diuretics Hydrochlorothiazide, Chlorothiazide, Bendroflumethiazide, Benzthiazide, Hydroflumethiazide, Methyclothiazide, Polythiazide, Trichlormethiazide (Diurese) Action is to block the chloride pump Keeps chloride and the sodium in the tubule to be excreted in the urine, thus preventing the reabsorption of both in the vascular system Indications – Treatment of edema associated with CHF, liver, or renal disease Contraindications – Fluid and electrolyte imbalances, and renal and liver disease – Bipolar disorders – Pregnancy and lactation Caution – Gout – Systemic lupus – Diabetes – Hyperparathyroidism Adverse Effects – Related to interference with the normal regulatory mechanisms of the nephron – Hypokalemia – Lithium Adverse Effects (cont.) – Decreased calcium excretion – Altered blood glucose levels – Urine will be slightly alkalinized

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LOOP DIURETICS Block the chloride pump in ascending loop of Henle. Causes reabsorption of sodium and chloride • Furosemide (Lasix) • Bumetanide (Bumex) and Torsemide (Demadex) • Ethacrynic acid (Edecrin)- used less frequently in the clinical setting Indications – Acute CHF – Acute pulmonary edema – Edema associated with CHF, renal or liver disease – Hypertension Contraindications – Electrolyte depletion – Anuria – Severe renal failure – Hepatic coma

Caution – SLE, gout, and diabetes mellitus Adverse Effects – Related to the imbalance in electrolytes and fluid – Hypokalemia (low potassium) – Alkalosis – Hypocalcemia (low calcium) Drug-to-Drug Interactions – Aminoglycosides or cisplatine increases risk of ototoxicity – Anticoagulation increase risk of bleeding – Indomethacin, ibuprofen, salicylates, or NSAIDs decreases anti-HTN effect CARBONIC ANHYDRASE INHIBITORS These drugs are used as adjuncts to other diuretics when a more intense diuresis is needed Block the effects of carbonic anhydrase; slow down the movement of hydrogen ions More sodium and bicarbonate are lost in the urine – Acetazolamide (Diamox) – Methazolamide (generic). • Indications – Glaucoma • Caution – Fluid or electrolyte imbalances – Adrenocortical insufficiency – Respiratory acidosis – COPD • Adverse Effects – Related to disturbances in acid and base balance and electrolyte balances – Metabolic acidosis – Hypokalemia – Paresthesias of extremities, confusion, drowsiness • Drug-to-Drug Interactions - Salicylates and lithium POTASSIUM-SPARING DIURETICS They retain potassium instead of wasting it. Cause a loss of sodium while retaining potassium Block the actions of aldosterone in the distal tubule – Amiloride (Midamor) – Spironolactone (Aldactone) – Triamterene (Dyrenium) Indications •

Patients who are at risk for hypokalemia(low potassium levels)

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Contraindications – Hyperkalemia, renal disease, or anuria – Patients taking amiloride or triamterene Adverse Effects – Hyperkalemia Drug-to-Drug Interactions – Salicylates: decreases anti-HTN & diuretic effect, increase risk of hyperkalemia, Na and water retention.

OSMOTIC DIURETICS Pull water into the renal tubule without sodium loss. – Mannitol (Osmitrol) • Indications Increased cranial pressure or acute renal failure due to shock, drug overdose, or trauma • Contraindications – Renal disease and anuria – Pulmonary congestion – Intracranial bleeding, dehydration – CHF • Adverse Effects – Related to sudden drop in fluid levels – Nausea, vomiting, hypotension, light-headedness, confusion, and headache...