Acetazolamide: mechanism of action

Acetazolamide

Acetazolamide is a reversible inhibitor of the carbonic anhydrase enzyme that results in reduction of hydrogen ion secretion at the renal tubule and an increased renal excretion of sodium, potassium, bicarbonate, and water. It can be used as a diuretic or to treat glaucoma as it prevents excessive build up of aqueous humor. It also inhibits carbonic anhydrase in the central nervous system to minimize abnormal and excessive discharge from CNS neurons. Acetazolamide can be administered to patients with a metabolic alkalosis to promote retention of hydrogen ions at the level of the renal tubule.

Mechanism of action: for the reduction of Intraocular pressure Acetazolamide inactivates carbonic anhydrase and interferes with the sodium pump, which decreases aqueous humor formation and thus lowers IOP. Systemic effects however include increased renal loss of sodium, potassium, and water secondary to the drug’s renal tubular effects. Arterial Blood gases may show a mild hyperchloremic metabolic acidosis.