Effect of orally administered nadolol on the intraocular pressure in normal volunteers.

Forty six normal volunteers were randomly assigned in double-blind fashion to once daily orally administered nadolol 10, 20, 40, or 80 mg for five days. Significant and dose related intraocular pressure (IOP) reductions (range 20-40%) were demonstrated both at three hours and 24 hours post dosing (p less than 0.001, all dosages). The reductions in IOP were dose related (p less than 0.05). One subject (in the 10 mg group) failed to show a significant intraocular pressure reduction. Significant reductions in blood pressure and heart rate also were recorded at all dose levels (with the exception of diastolic pressure in the 10 mg group), though considerably less in degree than IOP reductions. Two subjects (20 mg and 80 mg groups) experienced known side effects of beta blocker therapy necessitating termination of the drug, and four others experienced mild side effects but had no difficulty completing the study. The results have prompted further investigation of the usefulness of low doses of oral nadolol as therapy in chronic simple glaucoma patients.