Pharmacokinetic profile of topical flunarizine in rabbit eye and plasma.

The purpose of this study was to determine the aqueous humor, cornea, iris-ciliary body, retina and plasma levels and pharmacokinetics of a new topical formulation containing 0.05% flunarizine upon single drop application. Albino rabbits were used and tissue samples were collected at 15, 30, 60, 120 and 240 min after instillation. Drug concentrations in ocular tissues and plasma were measured by gas chromatography assay. After single dose application peak levels of drug were achieved at 15 min in cornea and at 30 min in aqueous humor, iris-ciliary body and retina. Unilateral topical flunarizine caused a significant reduction of intraocular pressure in rabbits. The pharmacokinetic profile showed a good ocular bioavailability of the drug providing that the new topical formulation containing 0.05% flunarizine reach the target tissues at effective concentrations and therefore may be use in the treatment of glaucoma.