The penetration of gentamicin into the vitreous humor in man.

Twenty-two patients received gentamicin intramuscularly or subconjunctivally 35-220 min prior to undergoing ocular surgery. There were no detectable gentamicin levels in the vitreous humor of patients who received the drug systemically. Of the patients who received gentamicin subconjunctivally, three quarters had no detectable gentamicin levels, only three of these patients had therapeutic concentrations in their vitreous humor. These results confirm kinetic drug studies performed in animals in which low or absent vitreal gentamicin levels were observed following systemic and subconjunctival administrations. It is suggested that intravitreal injection of aminoglycosides is required in the treatment of bacterial endophthalmitis.