Fixed drug eruption to mefenamic acid: a report of three cases.

Mefenamic acid (Ponstan) is widely used in the treatment of dysmenorrhoea, menorrhagia, and musculoskeletal pain. Although only 17 cases of fixed drug eruption provoked by mefenamic acid have been reported in the world literature, in a 7-day period a further three patients with fixed drug eruption due to mefenamic acid presented to the dermatology out-patient clinic of the University Hospital of Wales, Cardiff. The lesions of all the patients became inflamed within a few hours of taking the drug, but two of the three patients failed to appreciate the association. There have been no further episodes of inflammation since the patients avoided mefenamic acid.