Topical carbonic anhydrase inhibitors.

Dorzolamide, a topically active carbonic anhydrase inhibitor, is an effective new glaucoma medication that creates a decrease in intraocular pressure similar to that produced by beta-blockers. When beta-blockers are contraindicated, dorzolamide may be used as a first-line therapy. It has excellent additivity with other topical ocular hypotensive medications, including beta-blockers and pilocarpine. Systemic side effects are minimal, particularly compared with those of oral carbonic anhydrase inhibitors. However, local side effects, including corneal edema in patients with borderline endothelial function, may occur. Decreased visual acuity and allergic reactions, which occur frequently, may curtail the use of dorzolamide in some patients.