Question
Frusemide
Answer
Furosemide is a high-efficacy loop diuretic.
MOA: furosemide → inhibits the Na⁺-K⁺-2Cl⁻ (NKCC2) cotransporter in the thick ascending limb of the loop of Henle → blocks reabsorption of Na⁺, K⁺, and Cl⁻ → marked natriuresis and diuresis (abolishes the medullary concentration gradient, so both dilution and concentration of urine are impaired).
Uses: acute pulmonary edema/acute left ventricular failure (rapid venodilation and diuresis), edema of cardiac/hepatic/renal origin, hypertensive emergencies (adjunct), hyperkalemia and hypercalcemia (promotes renal excretion), acute renal failure to maintain urine output.
Adverse effects: hypokalemia, hyponatremia, hypochloremic metabolic alkalosis, ototoxicity (especially with rapid IV administration or renal impairment), hyperuricemia, hypovolemia/hypotension.