The effect on diurnal intraocular pressure of the fixed combination of latanoprost 0.005% and timolol 0.5% in patients with ocular hypertension

Abstract

Purpose: To measure the effect on intraocular pressure (IOP) after single-dose administration of the fixed combination of latanoprost 0.005% and timolol 0.5%. Methods: A randomized, double-masked placebo-controlled parallel-group study was carried out. Twenty patients with ocular hypertension received the fixed combination of latanoprost+timolol, while 10 received placebo eyedrops. On baseline day no eyedrops were given, but IOP was measured repeatedly between 8.00 a.m. and 8.00 p.m. On Day 7 the eyedrops were given at 8.00 a.m., and IOP measured as no baseline day. On Day 8 and Day 9, IOP was again measured at 8.00 a.m. Results: There was no difference in IOP in the placebo group. In the latanoprost+timolol group maximal IOP reduction (12.4±2.8 mmHg; mean±standard deviation) occurred 6.4 hours after drug administration (5.2-7.7 hours; 95% confidence interval [CI]. The mean IOP reduction after 24 hours was 9.8 mmHg (7.4-12.2 mmHg; 95% CI; p<0.001), and after 48 hours 5.7 mmHg (3.4-8.1 mmHg; 95% CI; p<0.001). Conclusions: The fixed combination of latanoprost+timolol statistically significantly reduced IOP after single-dose administration. The maximal effect was noted after about 6 hours, and the IOP reduction was still pronounced after 48 hours.