In a 65-year old man complaining of myalgias and loss of muscular strength, the creatine phosphokinase level was found to be 35 times higher than normal values. The electromyogram was of the diffuse myogenic type. Muscle biopsy showed necrotic lesions of the muscle fibres associated with perivascular infiltrates of mononuclear cells, leading to the diagnosis of polymyositis. This patient had been treated for 10 years with fenofibrate for hyperlipidaemia; during the last 32 months he had taken this drug in doses of 600 mg per day. Eight days after fenofibrate was discontinued, all clinical and laboratory abnormalities had disappeared. A reintroduction test performed 6 weeks later raised the creatine phosphokinase level up to 43 times the normal value. Withdrawal of fenofibrate therapy resulted in rapid and lasting recovery. This case shows that fenofibrate should be added to the list of drugs that are responsible for iatrogenic polymyositis.