We describe the case of a young woman who habitually took large doses of a combination of diphenhydramine and pyrithyldione. She complained of arthralgia, painful recurring plaques and nodules, together with persistent reticular purpuric mottling and areas of necrosis on her legs. There were positive antinuclear antibodies and rheumatoid factor and histologically massive thrombosis of the dermal vessels without signs of vasculitis. Other cases of similar adverse reactions attributed to this drug combination used as a hypnotic have been described.