Desmopressin
Indications
Desmopressin is used for:
Diabetes Insipidus, Primary nocturnal enuresis
Adult Dose
Nasal
Cranial diabetes insipidus
Adult: 10-40 mcg daily as a single or divided doses.
Diagnosis of diabetes insipidus
Adult: 20 mcg as a single dose.
Renal function testing
Adult: 40 mcg as a single dose.
Primary nocturnal enuresis
Adult: 20-40 mcg at bedtime.
Nocturia associated with multiple sclerosis
Adult: 10-20 mcg at bedtime.
Type I Von Willebrand's disease
Adult: 300 mcg; <50 kg: 150 mcg. Should be given within 2 hr before the surgery.
Child Dose
Nasal
Cranial diabetes insipidus
Child: 3 mth-12 yr: 5-30 mcg daily.
Diagnosis of diabetes insipidus
Child: 20 mcg as a single dose.
Renal function testing
Child: 1-15 yr: 20 mcg and infants: 10 mcg. To be given as a single dose.
Primary nocturnal enuresis
Child: >5 yr: 20-40 mcg at bedtime.
Renal Dose
Administration
Contra Indications
Hypersensitivity. Impaired renal function (CrCl <50 ml/min). De compensated cardiac failure with ongoing diuretic treatment.
Precautions
Nasal route avoided in patients with nasal mucosal diseases. Caution in CV diseases, oedema states, impairment, hypertension, elderly, cystic fibrosis, fluid and electrolyte imbalance, thrombotic disease; infants and young children.
Pregnancy-Lactation
Interactions
Drugs that may potentiate antidiuretic effect of desmopressin: chlorpropamide, clofibrate, carbamazepine, fludrocortisone, urea, or TCAs. Drugs that may decrease antidiuretic effect of desmopressin: lithium, heparin, demeclocycline, noradrenaline, and alcohol. Caution when using with other vasopressors.
Adverse Effects
Side effects of Desmopressin :
Nausea, transient headache; nasal congestion, rhinitis; flushing; mild abdominal cramps; epistaxis; sore throat, cough, stuffiness; allergic reactions, BP changes and thrombotic events in predisposed individuals.
Potentially Fatal: Water intoxication and dilutional hyponatraemia.
Mechanism of Action
Desmopressin increases the cellular permeability of the collecting ducts causing an increased water reabsorption, smooth muscle constriction. It also stimulates factor VIII and plasminogen activation activity in blood.