Comparative grepafloxacin phototoxicity in mouse skin

This study was performed in order to compare the phototoxic potential of grepafloxacin (a new fluoroquinolone for the treatment of respiratory tract infections) with that of a number of marketed fluoroquinolones. Groups of Balb/c mice received either control material or grepafloxacin, lomefloxacin, sparfloxacin, ofloxacin, ciprofloxacin or enoxacin at an oral dose of 200 mg/kg before being exposed to 20 J/cm2 longwave ultraviolet irradiation for 110-115 min. Lomefloxacin and sparfloxacin caused erythema and oedema which were often severe and lasted the full 7 days of the study. Enoxacin caused a long-lasting erythema, while the erythema seen following the administration of grepafloxacin, ciprofloxacin and ofloxacin was relatively mild and short-lived. The results of this study demonstrate the good safety profile of grepafloxacin in terms of phototoxicity.