Efficacy of peritoneal dialysis in severe thiazide-induced hyponatraemia

A patient with severe thiazide-induced hyponatraemia (plasma sodium 99 mmol/l) is described, who had signs suggestive of cerebral oedema. Co-existent problems of cardiac and respiratory insufficiency were thought to make treatment with hypertonic saline hazardous. A 40-hr peritoneal dialysis successfully reversed both hyponatraemia and the associated cerebral signs, plasma sodium increasing at a rate of 0·83 mmol/hr. Peritoneal dialysis appears to be a safe and efficacious method of treating severe thiazide-induced hyponatraemia.