Ocular penetration of cefepime following systemic administration in humans

OBJECTIVE: To investigate the penetration of cefepime (a fourth generation cephalosporin) into the aqueous humor after single-dose intravenous adminis tration in humans. PATIENTS AND METHODS: Before receiving cataract surgery, 30 patients receiv ed randomly 1 g (group 1, 15 patients) and 2 g (group 2, 15 patients) singl e intravenous injection of cefepime before surgery. Samples of aqueous humo r and serum were obtained at 0.5, 1, 2, 4, and 12 hours after injection. Th ree patients were sampled each time for 1 g and 2 g of cefepime. Samples we re assayed for cefepime concentrations with high performance liquid chromat ography (HPLC). RESULTS: All the patients had detectable cefepime in their aqueous humor an d serum measurable by HPLC. A mean peak aqueous humor level was 5.16 +/- 0. 88 mug/mL in group 1 and 5.87 +/- 1.64 mug/mL in group 2 at 0.5 hour after injection. The mean level of cefepime in aqueous humor decreased after 0.5- hour measurements in both groups and was measured as 0.82 +/- 0.21 mug/mL i n group 1 and 2.04 +/- 0.30 mug/mL in group 2 at 12 hours after injection. CONCLUSION: Aqueous humor levels of cefepime after single IV injection were above the minimum inhibitory concentration (MICS,) for most ocular pathoge ns, but the duration of exposure to an antibiotic was not sufficient for th erapeutic effect.