Intravitreal toxicity of levofloxacin and gatifloxacin.
To assess the retinal toxicity of varying concentrations of intravitreally injected gatifloxacin and levofloxacin.



In this experimental, controlled study, levofloxacin (initial concentration = 25 mg/mL) and gatifloxacin (initial concentration = 2 mg/mL) were titrated using 5% dextrose solution to concentrations of 2,500 to 156 microg/0.1 mL and 400 to 50 microg/0.1 mL, respectively. Each concentration was injected intravitreally into two rabbit eyes (one eye per animal); two control eyes were injected with 0.1 mL of 5% dextrose solution. All animals were examined and electroretinography was performed before and 14 days after injection. The animals were killed at 14 days; the eyes were enucleated and prepared for light microscopy.



The levofloxacin group exhibited significant decreases in electroretinography in the eyes injected with 1,250 and 2,500 microg. No signs of retinal toxicity were observed on slit-lamp examination, indirect ophthalmoscopy, or light microscopy in all eyes injected intravitreally with 625 microg or less of levofloxacin or in any eyes given gatifloxacin.



Intravitreally injected concentrations of 625 microg or less of levofloxacin and 400 microg or less of gatifloxacin appeared nontoxic.
Kazi
Abdul Ahad
AA
Department of Ophthalmology, Tulane University Health Sciences Center, 1430 Tulane Avenue, SL-69, New Orleans, LA 70112-2699, USA.
Jermak
Christopher M
CM
Peyman
Gholam A
GA
Aydin
Erdinc
E
Riazi-Esfahani
Mohammad
M
D000818:Animals; D000900:Anti-Bacterial Agents / Q000633:toxicity*; D004596:Electroretinography / Q000187:drug effects; D024841:Fluoroquinolones / Q000633:toxicity*; D000077734:Gatifloxacin; D007267:Injections; D064704:Levofloxacin; D015242:Ofloxacin / Q000633:toxicity*; D011817:Rabbits; D012160:Retina / Q000187:drug effects* / Q000473:pathology; D014822:Vitreous Body / Q000187:drug effects*
D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D064704:Levofloxacin; D015242:Ofloxacin; D000077734:Gatifloxacin