Erythema multiforme-like eruption in association with severe headache following pyritinol.

A 46-year-old woman presented with an unusual erythema multiforme-like eruption and severe headache 10 days after treatment with pyritinol for cerebral concussion. Histopathologic findings were consistent with erythema multiforme. Skin lesions and headache cleared after withdrawal of the drug. According to neurological examination and magnetic resonance imaging of the brain, the headache may have resulted from a slight, pyritinol-induced vasculitis. Previous reports on severe pyritinol-induced side effects and possible pathogenetic mechanisms are reviewed. Since pyritinol cannot be considered as an essential drug for cerebral concussion, adverse effects as described here raise doubts as to its general use in the given indication.