Comparison of Latanoprost/Timolol with Carbonic Anhydrase Inhibitor and Dorzolamide/Timolol with Prostaglandin Analog in the Treatment of Glaucoma

Purpose. We retrospectively reviewed medical records of glaucoma patients to investigate how switching medications may affect intraocular pressure (IOP) management. Three concomitant medications were changed to two medications: one combination drop and one single-action drop. Associated adverse effects were also examined. Subjects and Methods. A total of 112 patients with primary open-angle glaucoma or ocular hypertension were examined. All patients were concomitantly using a prostaglandin (PG) analog, a β-blocker, and a carbonic anhydrate inhibitor (CAI). Fifty-five patients began using latanoprost (PG analog)/timolol (β-blocker) fixed-combination (LTFC) drops and a CAI (group 1), and 57 patients began using dorzolamide (CAI)/timolol fixed-combination (DTFC) drops and a PG analog (group 2). The IOP was measured every 6 months for 2 years following medication changes. Changes in visual field mean deviation (MD) and medication discontinuations were also examined. Results. There were no significant differences in IOP or MD values before and after medication changes in either group. The proportion of medication discontinuations, uncontrolled IOP, and adverse reactions was similar in both groups. Conclusion. Switching patients from multiple single-action medications to combination medications was not associated with changes in IOP, visual field testing results, or adverse event frequency.