Timolol/dorzolamide combination therapy as initial treatment for intraocular pressure over 30 mm Hg

To determine the intraocular pressure (IOP)-lowering effect of a fixed timolol/dorzolamide combination (Cosopt) for patients with IOP over 30 mm Hg.

Prospective interventional case series.

Eighteen patients being seen on the Wills Eye Hospital Glaucoma Service with at least one eye with an IOP > 30 mm Hg were recruited. None had used any glaucoma medications for at least 1 month. IOP was confirmed by diurnal testing. Cosopt was administered at 9 am and 9 pm. Trough IOP measurements were made at 9 am and peak IOP measurements at 11 am at baseline, 1 month, and 2 months. Pretreatment and posttreatment IOPs were compared using a paired-samples independent t test.

Mean pretreatment IOP was 37.5 +/- 1.0 mm Hg. Baseline posttreatment IOP was 18.4 +/- 0.5 mm Hg (P < 0.01). At 2 months, the mean trough IOP was 21.1 +/- 0.9 mm Hg and the peak, 17.6 +/- 0.6 mm Hg (each, P < 0.01, as compared with pretreatment baseline IOP). One patient did not respond to Cosopt; two had a clinically insufficient response and did not complete the study. Data from these patients were included in the analysis.

Over 80% of the eyes responded to Cosopt, with an average trough IOP reduction of 40% at 2 months.