This site is intended for healthcare professionals
Last reviewed dd mmm yyyy. Last edited dd mmm yyyy
Symptoms depend on the severity of hyponatraemia and the rate of decrease in the plasma sodium concentration (1).
Signs and symptoms of hyponatraemia are often initially non specific (3)
Features of moderately severe hyponatraemia i.e. plasma sodium less than 120 mmol/l):
Features of severe hyponatraemia i.e. plasma sodium less than 110 mmol/l):
Patients with chronic hyponatraemia are unlikely to have any symptoms except during an acute exacerbation of the hyponatraemia (4).