A comparison of the efficacy and tolerability of dorzolamide and acetazolamide as adjunctive therapy to timolol

Purpose: To compare the efficacy and tolerability of dorzolamide to acetazo lamide. Methods: Following a timolol and acetazolamide run-in, 105 patients with el evated intraocular pressure (IOP) were randomized to dorzolamide or acetazo lamide, in addition to timolol, for 12 weeks. Results: More patients receiving acetazolamide discontinued due to clinical adverse experiences than patients receiving dorzolamide; 13 (25%) vs. 1 (2 %); p<0.001. The prevalence of systemic adverse experiences for the dorzola mide group dropped by 50% by Week 12, but remained unchanged for the acetaz olamide group, as compared to baseline; p<0.001, Ocular burning/stinging wa s more common in the dorzolamide group (21% vs. 0%; p<0.001), The mean trou gh IOP at Day 1 and Week 12 were 20.5 mmHg and 21.8 mmHg for the dorzolamid e group, and 20.4 mmHg and 20.5 mmHg for the acetazolamide group. The mean peak IOP at Day1 and Week 12 were 18.9 mmHg and 20.0 mmHg for the dorzolami de group, and 18.7 mmHg and 18.6 mmHg for the acetazolamide group. Conclusions: Mean IOP was slightly lower (by approximately 1 mmHg) with ace tazolamide, while dorzolamide demonstrated much better tolerability.