Which drug is an ophthalmic beta-blocker used to treat glaucoma?

• A. Timolol
• B. Propranolol
• C. Nadolol
• D. Betaxolol

Answer: (B)

Beta-blockers lower intraocular pressure in glaucoma by blocking beta receptors in the ciliary body, which reduces aqueous humor production. The classic ophthalmic beta-blocker used for this purpose is timolol, delivered as eye drops, and it effectively lowers pressure by cutting fluid formation. Betaxolol is another topical option that is beta-1 selective, which can be advantageous in patients where avoiding beta-2 blockade (and potential bronchospasm) is important. Propranolol and nadolol are mainly systemic beta-blockers and aren’t used as standard topical eye drops for glaucoma due to less targeted ocular effects and greater risk of systemic side effects. Thus, timolol is the primary ophthalmic beta-blocker for glaucoma treatment.