Allergic photocontact dermatitis due to suprofen. Photopatch testing and cross-reaction study

We report 5 cases of photocontact dermatitis due to suprofen, a nonsteroidal anti-inflammatory drug introduced to the Japanese market in 1989, and available as a 1% ointment. The patients developed pruritic eczematous lesions after applying the ointment for from 2 weeks to 3 months. All 5 patients reacted positively to photopatch testing with ultraviolet A (UVA) and suprofen down to 0.1-0.01% pet., and 3 patients showed positive reactions with ultraviolet B (UVB) and suprofen down to 1.0-0.1%. Moreover, all patients showed a cross-reaction with tiaprofenic acid, which has a very similar chemical structure to suprofen. However, there was no cross-reaction between suprofen and ketoprofen. Prescribers should be aware of the existence of photocontact sensitivity due to these drugs.