Desmopressin

Desmopressin (DDAVP) pituitary diabetes insipidus (DI) results from a deficiency of antidiuretic hormone (ADH) secretion. Desmopressin is an analogue of ADH. Treatment may be required for a limited period only in DI following head trauma or pituitary surgery. It is also used in the differential diagnosis of DI. Restoration of the ability to concentrate urine after water deprivation confirms a diagnosis of pituitary DI. Failure to respond occurs in nephrogenic DI.

Uses
Pituitary DI – diagnosis and treatment

Administration
• Diagnosis
   Intranasally: 20 μg
   SC/IM: 2 μg
• Treatment
   Intranasally: 5–20 μg once or twice daily
   SC/IM/IV: 1–4 μg daily
   Monitor fluid intake
   Patient should be weighed daily
Orally: 100–200 μg three times per day (range 50 μg twice daily up to 400 μg three times per day)

Adverse effects:
Fluid retention
Hyponatraemia
Headache
Nausea and vomiting

Cautions:
Renal impairment
Cardiac disease
Hypertension
Cystic fibrosis