About Acetazolamide Carbonic Anhydrase Inhibitor, Anticonvulsant, Diuretic, Ophthalmic Agent- Antiglaucoma. Mechanism of Action of Acetazolamide It is a sulfonamide derivative of carbonic anhydrase enzyme inhibitor. It exerts it`s diuretic, anti glaucomal, anti convulsant, anti altitude sickness actions by non competitively and reversibly inhibiting carbonic anhydrase in renal proximal tubules, ciliary body of eye, brain, lungs and tissues etc. Diuretic action: The inhibition of carbonic anhydrase at proximal renal tubules resulting in slowing of hydration of carbon dioxide which leads to decreased availability of H+ to exchange with luminal sodium. Inhibition of brush border carbonic anhydrase retards dehydration of carbonic acid in the tubular fluid so that less carbon dioxide diffuses back in to the cells. Thus inhibits bicarbonate and Na+ reabsorption in proximal tubules.