Desmopressin Nasal Spray Dosage
For central diabetes insipidus, the recommended adult dosage of desmopressin nasal spray is 0.1 to 0.4 mL daily (10 to 40 mcg), typically divided into two doses, with most adults requiring 0.2 mL daily (20 mcg total) in two divided doses. 1
Adult Dosing for Central Diabetes Insipidus
- Standard dosing range: 0.1 to 0.4 mL daily (equivalent to 10 to 40 mcg), administered either as a single dose or divided into two or three doses 1
- Most common regimen: 0.2 mL daily (20 mcg total) divided into two separate doses 1
- Dose adjustment: Morning and evening doses should be separately titrated to establish an adequate diurnal rhythm of water turnover, ensuring adequate sleep duration and appropriate (not excessive) water turnover 1
- Monitoring: Urine volume should be monitored intermittently to guide dose adjustments 2
Pediatric Dosing (Ages 3 Months to 12 Years)
- Dosage range: 0.05 to 0.3 mL daily (5 to 30 mcg), either as a single dose or divided into two doses 1
- Single daily dosing: Approximately 25-33% of pediatric patients can be controlled with once-daily administration 1
Administration Technique
- Nasal spray pump: Delivers only 0.1 mL (10 mcg) increments; must be primed with 5 pumps before first use 1
- Discard after 50 sprays: The amount delivered per spray may be substantially less than 10 mcg after this point 1
- Alternative delivery: If doses other than 0.1 mL multiples are required, use the rhinal tube delivery system 1
Critical Safety Considerations
- Fluid restriction is mandatory: For patients on any desmopressin formulation, evening fluid intake should be limited to 200 mL or less with no drinking until morning to prevent water intoxication and hyponatremia 2
- Nasal congestion: Patients with nasal congestion and blockage often still respond well to intranasal desmopressin 1
- Elderly patients: Exercise caution with dose selection due to increased risk of impaired renal function and toxic reactions; renal function monitoring may be useful 1
Important Clinical Pitfalls
The nasal spray formulation has higher bioavailability and greater intraindividual pharmacokinetic variability compared to oral tablets, which may contribute to the higher frequency of hyponatremia reports with this formulation. 3 Hyponatremia in younger patients typically results from overdosing and insufficient fluid restriction rather than inherent drug properties 3. The median conversion factor from nasal to oral desmopressin is approximately 20:1 (meaning 1 mcg nasal equals roughly 20 mcg oral) 4, though wide inter-individual variation exists in dose requirements 4.