Betaxolol and acetazolamide. Combined ocular hypotensive effect

To determine the combined ocular hypotensive effect of topical betaxolol hydrochloride and oral acetazolamide, we conducted a three-week clinical trial of the concurrent administration of the two drugs. One drop of betaxolol hydrochloride 0.5% every 12 hours effected a mean reduction in outflow pressure from baseline of 27.3%. When given topically to both eyes of a patient pretreated with oral acetazolamide (500 mg every 12 hours), betaxolol caused an additional mean outflow pressure decrease of 17.6%. Acetazolamide, 500 mg orally every 12 hours, produced a mean outflow pressure reduction from baseline of 42.5%. When added to the therapy regimen of a patient already receiving topical betaxolol, oral acetazolamide caused an additional mean outflow pressure decrease of 35.1%. Our study supports the clinical usefulness of concurrent administration of betaxolol and acetazolamide to lower intraocular pressure.