The mechanism of betaxolol, a new ocular hypotensive agent

A single drop, double-masked study was performed using 1% betaxolol ophthalmic solution in 24 normal subjects. Subjects received one drop of this new drug to one eye and a placebo drop to the fellow eye. Aqueous humor flow was measured using the technique of fluorophotometry, and outflow resistance was measured using tonography. Betaxolol suppressed aqueous humor flow in all individuals. The range of suppression was from 7 to 51%, with a mean suppression of 32 +/- 13%. The drug had no consistent effect on outflow resistance, and no pupillary changes were seen.