The effectiveness of dapiprazole in preventing exercise-induced IOP increase in patients with pigmentary dispersion syndrome

Abstract

Purpose. The authors investigated the use of dapiprazole, an alpha-adrenergic blocking agent, in preventing pigment release and IOP increase after exercise in patients affected with PDS. Methods. Three young myopic males (31, 34 and 35 years old) affected with pigmentary dispersion syndrome performed 30 minutes of jogging on a computerized treadmill. Telemetric heartbeat measurement was performed to obtain constant pulse rate training. Computerized tonography and IOP measurement were performed 10 minutes after the exercise. After one month the patients repeated the same exercise after pre-treatment with dapiprazole 0.5% eyedrops (one drop 30, 20 and 10 minutes before the exercise). Ten minutes after the exercise IOP measurements and computerized tonography were repeated. Results. After 30 minutes of exercise IOP measurements showed values ranging from 19 to 45 mmHg (mean 30.33; SD 8.73). Computerized tonography C values after exercise ranged from 0.04 to 0.16 (mean 0.09; SD 0.04). After pre-treatment with dapiprazole 0.5% eyedrops, IOP values ranged from 18 to 28 mmHg (mean 23.33; SD 3.44) and tonography C values ranged from 0.10 to 0.20 (mean 0.14; SD 0.03). Conclusions. The study supports the concept that exercise-induced pigment release temporarily obstructs the acqueous outflow channels, causing IOP increase in some patients with PDS. Pre-treatment with dapiprazole was useful in reducing IOP spikes and in increasing tonographic total outflow facility after exercise. The absence of induced myopia and the lack of dangerous vitreoretinal tractions on retinal periphery make dapiprazole a safe method to reduce exercise-induced pigment dispersion.