Fluoroquinolone antibacterial eye drops: Effects on normal human corneal epithelium, stroma, and endothelium

Background: In vitro studies have suggested the corneal cytotoxicity of third-generation fluoroquinolone levofloxacin (LVFX) and fourth-generation fluoroquinolone moxifloxacin hydrochloride (MFLX) among fluoroquinolone antibacterial eye drops. This study investigated the effects of these two eye drops on the human cornea in vivo. Methods: We evaluated 30 healthy adults (19 men and 11 women, 38.3 ± 6.3 years old). Each subject received an LVFX ophthalmic solution 0.5% in one eye and an MFLX ophthalmic solution 0.5% in the other eye three times daily for 7 days. Functional and morphological corneal changes before and after instillation were evaluated through ophthalmic examinations including breakup time of tear film (BUT) as measured by fluorescein staining and DR-1, Schirmer I test, Heidelberg Retina Tomograph II Rostock Cornea Module (HRTII-RCM), specular microscope, and Pentacum examination. Results: Both the LVFX and MFLX groups had no significant change in each examination before and after instillation. There was also no statistically significant difference in measurements after the 7-day instillation between the groups. Conclusion: Our study results suggest that as with LVFX, MFLX used in a normal clinical setting is unlikely to cause any obvious adverse effects on human normal cornea.