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Ocular comfort of combination glaucoma therapies: brimonidine 0.2%/timolol 0.5% compared with dorzolamide 2%/timolol
Kenny Chan1, Madalena Testa, Peter McCluskey
1Department of Ophthalmology, Liverpool Hospital, Liverpool, New South Wales, Australia.
Purpose:
Successful management of glaucoma and ocular hypertension requires patient compliance with the therapeutic regimen. Because ocular discomfort affects compliance, we compared the comfort of brimonidine 0.2%/timolol 0.5% and dorzolamide 2%/timolol 0.5%.
Methods:
In this single-centre, randomized, double-masked, internally controlled/paired-eye study, 30 subjects without a significant ocular surface disease received brimonidine 0.2%/timolol 0.5% in 1 eye and dorzolamide 2%/timolol 0.5% in the fellow eye. They evaluated discomfort at 30-40 s and 5 min postinstillation.
Results:
At 30-40 s, brimonidine 0.2%/timolol 0.5% provided significantly lower mean ocular discomfort scores than dorzolamide 2%/timolol 0.5% (P < 0.0001). This pattern persisted at 5 min but was not statistically significant. Significant differences were seen in the subjects' determination of the more comfortable treatment (P < 0.0001): brimonidine 0.2%/timolol 0.5% was rated as more comfortable than dorzolamide 2%/timolol 0.5% by 80% of subjects at 30-40 s and by 27% at 5 min. Only 10% of subjects at each time point rated dorzolamide 2%/timolol 0.5% as more comfortable. The remaining subjects reported no preference at either time point. No adverse events were reported.
Conclusions:
Brimonidine 0.2%/timolol 0.5% was significantly more comfortable than dorzolamide 2%/timolol 0.5% upon instillation. Patients with ocular hypertension or glaucoma may be more compliant with brimonidine 0.2%/timolol 0.5% treatment.
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