Intravitreal Toxicity of Moxifloxacin

Abstract

Abstract: : Purpose: To assess the retinal toxicity of various concentrations of intravitreally administered moxifloxacin, a fourth–generation fluoroquinolone. Methods: Ten New Zealand albino rabbits were divided into five groups of two animals. The animals were anesthetized and treated in accordance with the ARVO statement on the use of animals in ophthalmic and visual research. The initial concentration of moxifloxacin (4 mg/ml) was titrated using 5% dextrose solution to the following concentrations: 320 µg/0.1 ml, 160 µg/0.1 ml, 100 µg/0.1 ml, and 50 µg/0.1 ml that were injected intravitreally into one eye of each rabbit. Two control eyes were injected intravitreally with 0.1 ml of 5% dextrose solution. All animals were examined before and after injection by indirect ophthalmoscopy and slit–lamp biomicroscopy; electroretinography (ERG) was performed on all animals. The animals were euthanized and their eyes were enucleated and examined with light microscopy. Results: Significant decreases in ERG were noted in the group injected with 320 µg/0.1ml of moxifloxacin. No significant ERG changes were observed in eyes injected with moxifloxacin at other concentrations. There were no signs of retinal toxicity on slit–lamp examination, indirect ophthalmoscopy, or light microscopy in any eyes injected with moxifloxacin concentrations of 160 µg or lower. Conclusions: Intravitreal injection of moxifloxacin at a concentration of 160 µg or lower appears to be nontoxic in the rabbit eye.

Keywords: antibiotics/antifungals/antiparasitics • drug toxicity/drug effects • endophthalmitis