Article date: September 2007
Desmopressin is a synthetic analogue of vasopressin, and is indicated for treatment of primary nocturnal enuresis (PNE); nocturia associated with multiple sclerosis when other treatments have failed; and diagnosis and treatment of vasopressin-sensitive cranial diabetes insipidus; it is also indicated for establishment of renal concentration capacity.
Desmopressin is available as a nasal or oral formulation. The PNE indication has been removed from all desmopressin nasal spray products because of an increased risk of adverse effects compared with the oral formulation (which remains available for treatment of PNE).
Desmopressin produces a sustained decrease in urine output and a decrease in plasma osmolality, which can result in hyponatraemia and water intoxication in the presence of inappropriate fluid intake. About 15 cases of hyponatraemia per 100 000 patient-years of exposure for nasal desmopressin have been reported, compared with 5 cases per 100 000 patient-years for oral formulations. Most cases of hyponatraemia associated with use of nasal desmopressin occurred in patients younger than 18 years who were receiving treatment for PNE. There have also been reports of severe hyponatraemia in patients treated with nasal desmopressin for cranial diabetes insipidus. Most cases of hyponatraemia associated with oral desmopressin have been reported in elderly patients being treated for nocturia, but cases have also been reported in children.
Advice for healthcare professionals:
- Nasal formulations of desmopressin should not be used for treatment of PNE
- All patients with PNE should start oral desmopressin at the lowest recommended dose, which should be increased only if necessary to achieve control of symptoms
- Healthcare professionals and patients should follow closely the advice on fluid intake in the Summary of Product Characteristics and the Patient Information Leaflet to avoid hyponatraemia
Article citation: Drug Safety Update September 2007, vol 1 issue 2: 7.