The efficacy of topical prophylactic antiglaucoma therapy in primary closed angle glaucoma in dogs: a multicenter clinical trial.

The ability of either 0.5% betaxolol (1 drop topically, bid; n=31) or a combination of 0.25% demecarium bromide and a topical corticosteroid (gentamicin/betamethasone) (DB/GB; 1 drop of each topically, sid; n=55) to prevent glaucoma in the fellow eye of dogs with unilateral, primary closed angle glaucoma (PCAG) was investigated in a multicenter, open-label, clinical trial. Untreated control dogs (n=20) developed glaucoma significantly sooner (median, eight mos; p less than 0.001) than dogs treated either with DB/GB (median, 31 mos) or betaxolol (median, 30.7 mos). Although DB/GB and betaxolol equally delayed or prevented the onset of glaucoma in the second eye, a less frequent dosing schedule for DB/GB suggests demecarium bromide in combination with a topical corticosteroid may be preferable to betaxolol in preventing PCAG in dogs.