Controlled Comparison of the Cardiovascular Effects of Levobunolol 0.25% Ophthalmic Solution and Betaxolol 0.25% Ophthalmic Suspension

The cardiovascular effects were compared of levobunolol 0.25% ophthalmic solution, betaxolol 0.25% ophthalmic suspension, and placebo in a randomized, double-masked, three-period, crossover study of 19 healthy, elderly (age, >60 years) volunteers at rest and during constant-speed treadmill exercise (2.7 mi/h at 10% grade) performed 30 min after dosing. Resting measurements of heart rate, blood pressure, and rate x pressure product (RPP) obtained immediately prior to exercise were not significantly different in patients treated with either active drug than in patients treated with placebo. During exercise, however, there were significant differences among treatment groups. Subjects treated with levobunolol showed significantly lower average heart rates, systolic blood pressures, and RPPs during the last 6 min of exercise compared with patients treated with betaxolol. Subjects treated with levobunolol also showed lower average systolic blood pressures and RPPs compared with patients treated with placebo. There were no significant differences in average heart rates, systolic blood pressures, or RPPs during the last 6 min of exercise between the betaxolol and placebo groups. During the post-exercise recovery period, patients treated with levobunolol showed lower heart rates and lower RPPs at several time intervals than did patients treated with betaxolol or placebo.