What are the recommended desmopressin (DDAVP) doses for adult central diabetes insipidus, children with nocturnal enuresis, and mild hemophilia A or von Willebrand disease, and how should dosing be adjusted in renal impairment?

Desmopressin (DDAVP) Dosing Recommendations

Nocturnal Enuresis in Children

For bedwetting in children, start with oral desmopressin 0.2 mg (one tablet) at bedtime, increasing to 0.4 mg (two tablets) if needed, taken at least 1 hour before sleep with mandatory fluid restriction to 200 mL or less in the evening. 1, 2, 3

Key Dosing Details:

• Oral tablets: 0.2-0.4 mg taken 1 hour before sleep 1, 2, 3
• Oral melt formulation: 120-240 μg taken 30-60 minutes before bedtime 3
• Intranasal spray (discouraged): 10-40 μg nightly (one to four sprays) if oral route unavailable 1
• Dose is not weight- or age-based 2, 3
• Maximum renal concentrating effect occurs 1-2 hours after administration 2

Critical Safety Mandate:

• Absolute requirement: Fluid restriction to 200 mL (6 ounces) or less from evening dose until morning to prevent water intoxication 2, 3
• Absolute contraindication: Polydipsia (excessive drinking) 2, 3
• Strongly avoid intranasal formulations due to higher hyponatremia risk 2, 3
• Monitor serum electrolytes during intercurrent illness 1

Treatment Monitoring:

• Implement regular short drug holidays to assess ongoing need 2, 3
• Obtain baseline urine dipstick and 2-day frequency-volume chart before starting 2, 3
• Expected response: 30% complete dryness, 40% partial response 2, 3

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Central Diabetes Insipidus in Adults

For central diabetes insipidus in adults, use intranasal desmopressin 10-40 μg daily (divided into 1-2 doses) or parenteral desmopressin 2-4 μg IV/subcutaneously. 4, 5

Dosing by Route:

• Intranasal: 10-40 μg daily, typically divided into 1-2 doses 4, 5
• Intravenous/subcutaneous: 2-4 μg daily 4, 5
• Parenteral dosing is approximately 1/10th the intranasal dose 4

Important Considerations:

• Desmopressin is the drug of choice for central diabetes insipidus due to selective antidiuretic activity without pressor effects 4, 5
• Close monitoring required when switching between formulations due to inter-subject variability 6
• Risk factors for hyponatremia include extremes of age, comorbidity, drug interactions, and intranasal formulations 6

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Hemophilia A and von Willebrand Disease

For mild hemophilia A or von Willebrand disease, administer desmopressin 0.3 μg/kg IV diluted in 50 mL saline infused over 30 minutes. 1, 7

Hemostatic Dosing:

• Standard dose: 0.3 μg/kg intravenously 1, 7
• Dilute in 50 mL saline and infuse over 30 minutes 1
• Alternative routes: subcutaneous injection or intranasal spray for home treatment 7
• Effect is immediate with 2-6 fold increases in factor VIII and von Willebrand factor 7

Clinical Context:

• First-line treatment for von Willebrand disease (occurs in ~1 in 100 patients) 1
• May be used in trauma patients on antiplatelet agents with identified platelet dysfunction 1
• Not recommended routinely in bleeding trauma patients without specific indications 1
• Concerns about thromboembolic complications have not been confirmed in meta-analyses 1

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Renal Impairment Considerations

Desmopressin is contraindicated in severe renal impairment (CrCl <30 mL/min) and requires close monitoring as clearance is affected by kidney function. 3

• Not recommended for isolated liver disease unless concomitant end-stage renal disease is present 3
• Increased hyponatremia risk in patients with renal dysfunction 6

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Common Pitfalls to Avoid

• Never use intranasal formulations for enuresis due to higher hyponatremia risk with seizures 2, 3
• Never skip fluid restriction counseling—inadequate restriction is the primary cause of water intoxication 2, 3
• Never continue indefinitely without drug holidays—prevents assessment of ongoing need 2, 3
• Never prescribe to patients with polydipsia—this is an absolute contraindication 2, 3
• Never assume formulations are interchangeable—monitor closely when switching due to variable pharmacokinetics 6