Intraocular pressure reduction of fixed combination timolol maleate 0.5% and dorzolamide 2% (Cosopt) administered three times a day

PURPOSE To evaluate the safety and efficacy in intraocular pressure (IOP) reduction of increasing Cosopt dosage from twice to three times a day. METHODS The study included patients with primary open-angle glaucoma or ocular hypertension. After a washout period, IOP was measured at baseline, after 4 weeks of treatment with Cosopt twice a day, and after another 4 weeks of treatment with Cosopt three times a day. Blood pressure, heart rate, and oxygen saturation levels were also recorded. RESULTS Twenty-nine eyes of 29 patients were included. Increasing Cosopt dosage resulted in a statistically significant (P < 0.001) additional reduction in IOP of 2.2 ± 1.58 mmHg (10.69% ± 7.49% of the baseline IOP values). There were no local or systemic adverse effects. CONCLUSION Treatment with Cosopt three times a day was more effective in reducing IOP than twice a day, with no effect on safety.