Ocular Irritation Through Topically Applied Betablockers

Summary

Six different ophthalmic betablockers were screened for ocular irritation in 10 volunteers and 30 glaucoma patients using a self-evaluation analogue scale and a negative-preference determination. One drop of drug solution in its commercial preparation was applied to one eye and one drop of balanced salt solution as a placebo reference to the fellow eye. A self-evaluation form was filled in immediately after application and 3 as well as 10 minutes afterwards. Ocular discomfort was mediated most by Metipranolol and Bupranolol eye drops, with Bupranolol irritating longest. Timolol and Carteolol ophthalmic solutions showed lowest irritation scores. Dose-dependence of ocular irritation could be verified for different concentrations of Bupranolol and Metipranolol. Mean irritation scores correlated well to the number of antiglaucomatous drugs in the patient’s history but not the disease duration. This simple method to screen for eye irritation induced by ophthalmic drug solutions turned out to be valid and sensitive enough.