Photocontact allergy to arylpropionic acid non-steroidal anti-inflammatory drugs in patients sensitized to fragrance mix I

Concomitant allergy to fragrance mix (FM) I and ketoprofen is known. It may be caused by sensitization to cinnamyl alcohol, a component of FM I.. The aim of this study was to assess the frequency of contact and photocontact allergy to some arylpropionic acid non-steroidal anti-inflammatory drugs (NSAIDs) in a series of 26 patients with contact allergy to FM I. Patch and photopatch tests were performed with the 8 ingredients of FM I and an arylpropionic acid NSAIDs series (ketoprofen, fenoprofen, flurbiprofen, ibuprofen, naproxen, and tiaprofenic acid, each at 1% in pet). An high frequency of sensitization to tiaprofenic acid (31%), alone or in combination with other NSAIDs, particularly ketoprofen (23% of the total), was observed. As tiaprofenic acid is not available in topical formulation in European countries, the photoreactions to this drug may be explained by cross-reactivity with ketoprofen, which is likely to be the true sensitizer in most cases. Our results suggest that sensitization to cinnamyl alcohol may be considered a marker or even a risk factor of photocontact allergy to ketoprofen and tiaprofenic acid. Among the arylpropionic acid NSAIDs available in topical forms, naproxen seems to be the safest drug in patients sensitized to cinnamyl alcohol and cross-reacting molecules.