Effect of topical 0.5% betaxolol administration on intraocular pressure in clinically normal dogs

Abstract

The aim of this study was to determine the effect of topically applied 0.5% betaxolol on intraocular pressure (IOP) in clinically normal dogs. Ten adult crossbred dogs without physical or ocular abnormalities were used in this study. Baseline IOPs were determined with the use of a Tono-Pen Vet. One drop of 0.5% betaxolol was administrated to a randomly chosen eye. All animals had their IOP measured at 15, 30, 60, 120, 360, and 720 min post-drug-administration. Results indicated that, 15 min after treatment, there was a significant decrease in IOP from baseline values in the treated (17.90 ± 2.12 mmHg) and untreated (21.20 ± 1.90 mmHg) eyes. The peak effect of topical 0.5% betaxolol in treated eyes was observed 2 h after treatment. We conclude that a single dose of topically applied 0.5% betaxolol significantly decreases IOP in the treated and contralateral eye in this small population of dogs.