Ceftriaxone-induced fixed drug eruption: first report.

Fixed drug eruption (FDE) is an unusual type of cutaneous adverse drug reaction that is characterized by recurrent site-specific lesions each time the drug responsible is taken. FDE from cephalosporins has been rarely reported, and to the best of our knowledge there is no published report of ceftriaxone-induced FDE in the literature. We report the first case of a 54-year-old Turkish woman who presented with ceftriaxone-induced FDE. Topical provocation with ceftriaxone sodium salt (1% in water [aq.], 5% aq., 10% in petrolatum [pet.], 20% pet.) remained negative both at previously affected sites and in the unaffected skin of the back. Therapeutic re-exposure with intravenous ceftriaxone 1 g confirmed the diagnosis. The patient tolerated amoxicillin and cefazolin, suggesting that the sensitizing portion was not the beta-lactam ring. Identification of the antigenic determinants of FDE-inducing drugs will make predicting safe alternatives in patients with FDE an easier task.