The efficacy of timolol maleate, dorzolamide hydrochloride and the association of both drugs on intraocular pressure (IOP) of healthy dogs was evaluated. Sixty adult dogs were randomly and equally assigned to three groups (n= 20 per group). Each group received topical treatment in the left eye with timolol maleate 0.5%, dorzolamide hydrochloride 2% or the association of both drugs. IOP measurements were made using aplanation tonometry (Tono-pen®) and they were performed one hour before (baseline) and at one, two, four, six and eight hours after treatment. Similar measurements were also performed in the right eye. In the treated eye, there was a higher reduction in IOP in animals that received the drugs association, 27% of maximum decrease from baseline as compared to timolol (decrease of 21.9%) and dorzolamide (decrease of 22.4%). In the non-treated eye, IOP decreased over time, with a maximum decrease from baseline of 7.0%, 13.8% and 13.6% in the timolol, dorzolamide e timolol/dorzolamide treatments, respectively.
dog; intraocular pressure; glaucoma; dorzolamide; timolol
