Vitreous penetration of levofloxacin in the uninflamed phakic human eye

Abstract

Aims: To assess the vitreous penetration of oral levofloxacin (a new fluoroquinolone antibiotic with improved Gram positive activity) in uninflamed phakic eyes. Methods: 15 patients for macula hole surgery were recruited to the study. 10 received a single 500 mg dose of levofloxacin by mouth preoperatively. Five acted as controls. Serum and undiluted vitreous samples were obtained at surgery and analysed by HPLC. Results: Levofloxacin was detectable 2.5 hours after administration in the vitreous. A peak concentration of 1.6 μg/ml (or mg/l) was measured between 2.5 and 4 hours post-dose. Conclusion: Oral levofloxacin reaches the vitreous rapidly in the uninflamed phakic eye. Levels did not reach MIC 90 for the commonest infecting organisms. Nevertheless, levofloxacin would be expected to be active against a higher proportion of infecting organisms than either ciprofloxacin or ofloxacin.