Nicolau syndrome after intramuscular injection: 3 cases.

Nicolau syndrome is a rare complication of intramuscular injection consisting of ischemic necrosis of skin, soft tissue, and muscular tissue that arises locoregionally. The characteristic pattern is pain around the injection site, developing into erythema, a livedoid dermatitis patch, and necrosis of the skin, subcutaneous fat, and muscle tissue. Three patients were injected with drugs (diclofenac sodium, ketoprofen, meperidine) for pain relief. Three patients complained of pain, and a skin lesion was observed, after which necrosis developed on their buttocks. Each patient underwent debridement and coverage. The wound healed uneventfully. We report three cases of Nicolau syndrome in the buttocks following diclofenac intramuscular injection.