Fourteen cases of acute severe pancreatitis complicated by non-traumatic rhabdomyolysis are described and compared to case controls. Pancreatitis of various aetiologies was confirmed by surgical diagnosis, laparotomy, abdominal paracentesis, CAT scan and post mortem. Pancreatitis was severe with a high Ranson prognostic score (7.4 +/- 0.5 vs controls 1.9 +/- 0.4, p less than 0.001), longer ICU admission and a mortality of 79%. Rhabdomyolysis occurred two to 19 days after the onset of pancreatitis (with a median CPK peak at 6.5 days) and was accompanied by multiple organ failure in 93% of cases. Severe rhabdomyolysis and myoglobinuric renal failure occurred in three patients out of 12 with acute renal failure. Hypocalcaemia was common (93%), severe (with a mean minimum value of 1.79 +/- 0.07 vs 2.34 +/- 0.04mmol/L, p less than 0.01) and prolonged (remaining abnormal for 5.2 +/- 0.8 vs 0.07 +/- 0.07 days, p less than 0.001). Intravenous calcium supplements were required in 50% of patients. Plasma phosphate, potassium, urate and anion gap were elevated (all p less than 0.05) and accompanying clinical features included fever, ascites, leucocytosis, hypoalbuminaemia and abnormal liver function tests. Rhabdomyolysis is associated with acute several pancreatitis, appearing as a late phenomenon in the context of severe prolonged hypocalcaemia, multiple organ failure and a poor outcome.