[Generalized convulsions in a patient with polydipsia and severe hyponatremia]

A case of a 40-year-old psychiatric patient is reported. Primarily, he was thought to have epileptic seizures, but demonstrated acute symptoms of severe hyponatraemia, plasma sodium was 106 mmol/l. Treatment was initiated with hypertonic saline until regression of symptoms, followed by slow correction of serum sodium to subnormal level. The patients outcome was good. This treatment is discussed focusing on the importance of an immediate onset, despite that the cause of hyponatraemia may be unknown.