Gatifloxacin belongs to which class and is used for what condition?

• A. Fourth-generation fluoroquinolone; post-operative corneal ulcers
• B. Beta blocker; glaucoma
• C. Corticosteroid; inflammatory conditions
• D. Carbonic anhydrase inhibitor; glaucoma

Answer: (A)

Gatifloxacin is a fourth-generation fluoroquinolone antibiotic formulated for topical use in the eye. Fourth-generation fluoroquinolones offer broad-spectrum coverage against both Gram-positive and Gram-negative bacteria and penetrate ocular tissues well, making them effective for treating postoperative ocular infections such as corneal ulcers. They work by inhibiting bacterial enzymes DNA gyrase and topoisomerase IV, which are essential for DNA replication and repair, thereby stopping bacterial growth. This makes gatifloxacin suitable for bacterial keratitis or corneal ulcers after surgery. It is not a beta blocker used for lowering intraocular pressure in glaucoma, a corticosteroid for inflammatory conditions, or a carbonic anhydrase inhibitor for glaucoma, which explains why those options don’t fit.