acetazolamide + hydrochlorothiazide + furosemide

This is a combination of three diuretic agents—acetazolamide, hydrochlorothiazide, and furosemide—used together to enhance diuresis in patients with conditions such as acute decompensated heart failure or severe fluid overload. - **Acetazolamide** is a carbonic anhydrase inhibitor that acts on the proximal tubule of the nephron, reducing bicarbonate reabsorption and promoting sodium and water excretion[7][9]. - **Hydrochlorothiazide** is a thiazide diuretic that inhibits sodium-chloride symporters in the distal convoluted tubule, increasing excretion of sodium and water[1][6]. - **Furosemide** is a loop diuretic that inhibits the Na-K-2Cl cotransporter in the thick ascending limb of Henle’s loop, leading to potent natriuresis and diuresis[3][5]. The rationale for combining these agents lies in their sequential blockade of different segments of the nephron (“sequential nephron blockade”), which can overcome resistance to single-agent therapy by maximizing natriuresis at multiple sites along the renal tubule. This approach has been shown to be more effective than monotherapy or dual therapy for achieving decongestion in acute heart failure patients who are resistant to standard doses of loop diuretics[1][2][4][8].