Ocular penetration of chloramphenicol. Effects of route of administration.

Chloramphenicol was applied topically to the eye in ointment, as a powder, or injected subconjunctivally and intravenously in rabbits. Aqueous humor samples were taken at varying time intervals up to six hours and analyzed for chloramphenicol using gas-liquid chromatography. The topical route using ointment and the subconjunctival injection route produced bacteriostatic concentrations of chloramphenicol in the aqueous humor lasting for several hours, while the topical powder and intravenous routes yielded relatively low concentrations. As compared with the other means of drug delivery, ointment was the most efficient in that it provided the highest aqueous concentration per total amount of drug administered.