OFLOXACIN PENETRATION INTO THE EYE AFTER INTRAVENOUS AND TOPICAL ADMINISTRATION

Abstract

Purpose: To determine the aqueous and vitreous fluid penetration of ofloxacin after a combined topical and single intravenous dose protocol before vitrectomy surgery. Materials and Methods: Before undergoing vitrectomy surgery, patients were given two drops of ofloxacin 0.3% topically and a single intravenous dose of ofloxacin 400 mg. Aqueous (mean, 43 minutes) and vitreous (mean, 53 minutes) fluid samples were collected at the start of the surgical procedure. The samples were analyzed for ofloxacin penetration. Results: The mean aqueous fluid concentration was 1.083 μg/mL ± 0.406. The mean ± SD vitreous fluid concentration in nondiabetic patients with intact vitreous was 0.352 μg/mL ± 0.301. Vitreous levels obtained more than 50 minutes after administration (0.414 μg/mL ± 0.336) were generally higher than those obtained after less than 50 minutes (P = 0.12). Eyes with prior vitrectomies achieved better ofloxacin penetration (0.984 μ/g/mL ± 0.680) than did nonvitrectomized eyes. Conclusion: Ofloxacin achieved measurable aqueous fluid penetration after topical and intravenous administration. Aqueous levels were above the minimum inhibitory concentration for most ocular pathogens. Vitreous levels were adequate in vitrectomized eyes to achieve inhibitory concentrations against many common ocular pathogens. Combined preoperative topical and a single dose of intravenous ofloxacin may provide inhibitory aqueous and vitreous antibiotic levels in vitrectomized eyes in cases where intravitreal antibiotics are not considered and oral administration is not practical. RETINA 17:535-539, 1997