Which diuretic class is used to treat open-angle glaucoma?

• A. Loop diuretics
• B. K+ sparing diuretics
• C. Carbonic Anhydrase Inhibitors
• D. Osmotic diuretic

Answer: (C)

Carbonic anhydrase inhibitors are used in open-angle glaucoma because they lower intraocular pressure by reducing the production of aqueous humor. They block the enzyme carbonic anhydrase in the ciliary body, which decreases bicarbonate formation and disrupts the active transport of ions and water into the posterior chamber. With less fluid being produced, the amount of aqueous humor in the eye drops, easing the pressure that can damage the optic nerve in glaucoma. This class is commonly used in topical forms (like dorzolamide or brinzolamide) or systemically (acetazolamide) to help manage chronic open-angle glaucoma. Other diuretics don’t target aqueous humor production in the same way, though osmotic diuretics can be used acutely to rapidly lower pressure, they’re not the standard long-term treatment for open-angle glaucoma.