Dermatitis herpetiformis exacerbated by indomethacin

Thirteen adults with dermatitis herpetiformis (DH) controlled by dapsone or sulphamethoxypyridazine were given indomethacin or placebo in a double-blind cross-over study. In nine of the thirteen patients the rash and pruritus of DH were exacerbated more by indomethacin than by placebo. Dapsone and sulphamethoxypyridazine requirements were increased during the indomethacin period. The involvement of lipoxygenase products in the pathogenesis of the DH skin lesions is postulated.