The ocular distribution of bunolol in the eyes of albino and pigmented rabbits.

The ocular administration of a 50 microL instillation of bunolol hydrochloride, a beta 1- and beta 2- adrenoceptor blocking agent, resulted in significantly higher drug levels in the choroid/retina, iris, and ciliary body of pigmented rabbits compared with albino rabbits following topical administration. The concentrations in these tissues also persisted longer in the pigmented rabbits' eyes. However, no statistically significant differences in tissue levels were observed in the cornea or conjunctiva. The results of this study support the previously reported finding with timolol which showed longer retention of the drug in the iris, ciliary, choroid, and retina of pigmented rabbits than albinos.