Cosopt is a combination glaucoma medication. Which two drugs constitute this product?

• A. Dorzolamide + Latanoprost
• B. Timolol + Dorzolamide
• C. Timolol + Latanoprost
• D. Brimonidine + Pilocarpine

Answer: (B)

Cosopt is defined by two active components that work in different ways to lower intraocular pressure. One is timolol, a nonselective beta-blocker that decreases aqueous humor production by blocking beta receptors in the ciliary body. The other is dorzolamide, a carbonic anhydrase inhibitor that also reduces aqueous humor formation by limiting bicarbonate production in the ciliary processes. Using these two together provides an additive effect, making it effective when single-drug therapy isn’t enough. The two drugs in Cosopt are timolol and dorzolamide. Other fixed combinations pair different drugs (for example, a prostaglandin analog with a beta-blocker or a brimonidine-based mix), so they are not Cosopt.