Comparison of the safety and efficacy of dorzolamide 2% and brimonidine 0.2% in patients with glaucoma or ocular hypertension.

PURPOSE: To compare the intraocular pressure (IOP) reduction between dorzolamide 2% and brimonidine 0.2% in primary open-angle glaucoma (POAG) or ocular hypertension (OHT).

METHODS

This study was a prospective, double-masked, randomized, crossover comparison of dorzolamide 2% (Trusopt) and brimonidine 0.2% (Alphagan), three times daily during two six-week study periods. The primary endpoint was mean change from baseline in trough IOP and secondary endpoints were mean change from baseline in IOP one and three hours after dosing. T-tests and a repeated-measures ANOVA were used to statistically evaluate the data.

RESULTS

Of 43 patients enrolled, 41 completed the first treatment and 38 completed both treatments. Baseline IOP for dorzolamide was 24.3 mm Hg and brimonidine, 24.6 mm Hg (P = 0.9). Mean IOP reduction at trough was similar for both agents, 3.0 mm Hg (P = 0.96). Reductions at one and three hours were comparable (P = ns). Both agents were well tolerated with adverse events consistent with the package inserts. Dorzolamide was associated with more frequent stinging (P = 0.017) and burning (P < 0.001), while brimonidine was associated with more frequent dry eye (P = 0.04).

CONCLUSIONS

Dorzolamide and brimonidine, as monotherapy, produced equivalent IOP-lowering efficacy at trough and at one and three hours after instillation, and both were well tolerated.