Nontoxic intravitreal dose of ofloxacin for rabbit retina.

We studied the nontoxic intravitreal concentration of ofloxacin, a new quinolone antibacterial agent, by evaluating its effects on in vitro and in vivo electroretinograms (ERGs) in albino and pigmented rabbits. After perfusion with a 36 micrograms/ml solution of ofloxacin, the in vitro ERG remained unchanged. The in vivo ERG and the visually evoked potential remained unchanged 4 weeks after vitrectomy with 50 micrograms/ml ofloxacin, and the retina was within normal limits both ophthalmoscopically and histologically. Therefore, the retinal toxicity of ofloxacin is low and within safe limits at clinical dosage.