Loop Diuretics
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Overview
Loop diuretics are the most potent class of diuretics, producing rapid and pronounced natriuresis and diuresis. Furosemide is the prototypical agent, used for edema associated with heart failure, hepatic cirrhosis, and renal disease, as well as hypertension and hypercalcemia.
How do loop diuretics work?
Loop diuretics inhibit the Na-K-2Cl cotransporter (NKCC2) in the thick ascending limb of the loop of Henle, blocking reabsorption of sodium, potassium, and chloride. This reduces the medullary concentration gradient required for water reabsorption, resulting in large volumes of isotonic urine. They also have vasodilatory effects that contribute to their efficacy in acute pulmonary edema.
Drugs in this class
- Furosemide (Lasix)