Comparison of the efficacy of betaxolol-brinzolamide and timolol-dorzolamide as suppressors of aqueous humor flow in human subjects

Objective: To compare the efficacy of combinations of betaxolol-brinzolamid e and timolol-dorzolamide as suppressors of aqueous humor flow and ocular h ypotensive agents. Design: Placebo-controlled, masked comparison of the two drug combinations. Participants: Twenty-five normal human volunteers with the fellow eye servi ng as control. Methods or Testing: Fluorophotometric measurement of aqueous humor flow and pneumatonometric measurement of intraocular pressure. Main Outcome Measures: Aqueous humor flow and intraocular pressure. Results: The betaxolol-brinzolamide combination lowered aqueous flow 39% to 44%, and the timololdorzolamide combination lowered aqueous flow 51%, The betaxolol-brinzolamide combination lowered intraocular pressure 14% to 19%, and the timolol-dorzolamide combination lowered it 18% to 24%, Conclusions: Both drug combinations were effective; the timolol-dorzolamide combination appeared to be the more effective of the two after short-term exposure (24 hours). (C) 2000 by the Mayo Foundation.