Evaluation of the comfort of Alphagan P compared with Alphagan in irritated eyes

The tolerability of brimonidine tartrate 0.15%--referred to as bromonidine-Purite 0.15% in this study--was compared with brimonidine tartrate 0.2% in irritated eyes of healthy volunteers as well as patients with glaucoma or ocular hypertension (N=20) in a 2-week, single-center, randomized, double-masked, crossover study. Participants were evaluated at days 0, 7, 11, and 15. At day 0, they were exposed to a controlled adverse environment (CAE), in which humidity, temperature, and airflow was regulated, for up to 90 minutes. Participants who reported a sufficient level of bilateral ocular discomfort during exposure to the CAE were enrolled in this study and received 1 drop of brimonidine-Purite 0.15% in 1 eye and 1 drop of brimonidine tartrate 0.2% in the contralateral eye. Immediately following instillation, participants were asked to indicate their preference for either study medication. The study medications were not used between days 0 and 7. From day 7 to 10, participants administered either drug bilaterally. On day 11, the treatment was crossed over, and participants were asked to compare the preferred medication with their previous regimen. They continued to administer the drug bilaterally twice daily until day 15, when the preferred medication was again compared with the previous regimen. Following CAE exposure at visit 1, 70.6% of the participants preferred brimonidine-Purite 0.15% over brimonidine tartrate 0.2% and indicated that it was significantly more comfortable than brimonidine tartrate 0.2% (P=.009). When given brimonidine-Purite 0.15% first before switching to brimonidine tartrate 0.2%, 80% of participants preferred brimonidine-Purite 0.15% (P=.012). When given brimonidine tartrate 0.2% first before switching to brimonidine-Purite 0.15%, 85% preferred brimonidine-Purite 0.15% (P=.001). The results of this study suggest that brimonidine-Purite 0.15% is significantly more comfortable than brimonidine tartrate 0.2% in patients with irritated eyes.