Water intoxication in a schizophrenic patient with rhabdomyolysis.

We report a case of water intoxication in a 54-year-old female schizophrenic patient with rhabdomyolysis. She had been admitted to a mental hospital, and treated with spiperone 6 mg daily. On August 3, 1992, the coma following a convulsion occurred. Laboratory data initially showed marked hyponatremia and hypochloremia with decreased serum potassium, and a gradual increase in serum creatine phosphokinase (CPK). The elevation in serum CPK with marked hyponatremia observed in the present patient was probably caused by excessive drinking of water. In this patient, the CPK elevation revealed the rhabdomyolysis.