Which two drugs on the list are carbonic anhydrase inhibitors?

• A. Acetazolamide and Methazolamide
• B. Netarsudil and Dorzolamide
• C. Difluprednate and Prednisolone
• D. Moxifloxacin and Gatifloxacin

Answer: (A)

Carbonic anhydrase inhibitors work by blocking the enzyme carbonic anhydrase, which in the eye helps form bicarbonate for aqueous humor production. When this enzyme is inhibited, bicarbonate formation decreases, leading to reduced sodium and water transport into the eye and lower production of aqueous humor, which lowers intraocular pressure. Acetazolamide and methazolamide are classic systemic carbonic anhydrase inhibitors used for this purpose.

The other options represent different drug classes: netarsudil is a Rho kinase inhibitor that enhances outflow to lower eye pressure, while difluprednate and prednisolone are corticosteroids, and moxifloxacin and gatifloxacin are fluoroquinolone antibiotics. Therefore, the two carbonic anhydrase inhibitors listed are acetazolamide and methazolamide.