Efficacy and adverse effects of medications used in the treatment of glaucoma

With the advent of several new topically active medications for glaucoma therapy, intraocular pressure (IOP) can be reduced to target levels in more patients before resorting to surgery. Some of these newer agents have a number of advantages over some of the older medications, several of which are seldom used now. The topically active carbonic anhydrase inhibitors are better tolerated than oral formulations, which are infrequently used despite their greater efficacy compared with the topical formulations. The α₂-adrenergic agonists effectively reduce IOP with few systemic adverse effects. The prostaglandin analogues are even more effective and well tolerated when applied once daily without known systemic adverse effects. The variety of glaucoma medications forces the physician to be selective with various combinations before proceeding with surgery. This article critically reviews the literature pertaining to the newer glaucoma medications, thereby providing guidelines to make rational choices from among the available options.