• nocturia;
  • elderly;
  • desmopressin;
  • safety;
  • hyponatremia


To investigate the short-term safety of desmopressin in elderly patients with nocturia, with special focus on the risk of hyponatraemia, and to assess the short-term effects on urine output, sleep and voiding patterns.


Patients (72) were recruited from a study using frequency-volume charts, which in turn was preceded by a questionnaire study. Each patient took one 0.2 mg desmopressin tablet at bedtime for three consecutive nights and kept a frequency-volume chart. Serum sodium was assessed in the morning after the first and the third dose. Patients with a mean serum sodium level during treatment deviating more than five units from baseline were considered sensitive to change in serum sodium. Potential predictors for sodium sensitivity and response were investigated with logistic and multiple regression.


All 72 enrolled patients completed the trial; no serious adverse events occurred and no adverse events of severe intensity were recorded. Six patients were sensitive to change in serum sodium. The risk (odds ratio, 95% confidence interval) increased with increasing age (1.3, 1.1–1.6), concomitant cardiac disease (10.0, 0.9–105.8) and increasing baseline 24-h urine output (1.2, 1.0–1.5). Patients sensitive to change in serum sodium were pharmacological responders and desmopressin had a greater effect on their 24-h diuresis, indicating that the drug effect was not limited to the night only.


Desmopressin was well tolerated in elderly patients with nocturia, but the results suggest that serum sodium should be measured before and after a few days of treatment.