Assessment of the Dermal and Ocular Irritation Potential of Lomefloxacin by Using In Vitro Methods

The evaluation of eye and skin irritation potential is essential to ensuring the safety of human in contact with a wide variety of substances. Despite this importance of irritation test, little is known with respect to the irritation potency of lomefloxacin, a fluoroquinolone antibiotic, which has been known to cause phototoxicity with an abnormal reaction of the skin. Thus, to investigate the tendency of lomefloxacin to cause eye and skin irritation, we carried out in vitro eye irritation test using Balb/c 3T3, and in vitro skin irritation test using KeraSkin(TM) human skin model system. 3T3 neutral red uptake assay has been proposed as a potential replacement alternative for the Draize Eye irritation test. In this study, the IC50 value obtained for lomefloxacin was 375 μg. According to the classification model used for determining in vitro categories, lomefloxacin was classified as moderately irritant. For evaluation of skin irritation, engineered epidermal equivalents (KeraSkin(TM)) were subjected to 10 and 25 mg of lomefloxacin for 15 minutes. Tissue damage was assessed by tissue viability evaluation, and by the release of a pro-inflammatory mediator, interleukin-1α. Lomefloxacin increased the interleukin-1α release after 15 minutes of exposure and 42 hours of post incubation, although no decrease in viability was observed. Therefore, lomefloxacin is considered to be moderately irritant to skin and eye.