Opiate-induced rhabdomyolysis.

Three patients with opiate self-poisoning developed acute muscle damage with elevated serum aspartate aminotransferase and creatine kinase activities, increased serum myoglobin concentrations, raised plasma creatinine concentrations, hypocalcaemia and hyperphosphataemia. These abnormalities gradually resolved over 7-10 days, but recovery was complicated due to the development of acute renal failure (requiring haemodialysis) in one patient. Plasma drug concentrations, shortly after admission, in the patients taking dihydrocodeine and morphine were grossly elevated (184 and 60 micrograms/l respectively). Clinical evidence of myopathy was minimal in all three patients and muscle biopsy of one patient was normal at 7 days.