What is the treatment for nocturnal enuresis using DDAVP (Desmopressin)?

DDAVP (Desmopressin) Treatment for Nocturnal Enuresis

DDAVP (desmopressin) is an effective pharmacological treatment for nocturnal enuresis, administered orally at 0.2-0.6 mg or intranasally at 10-40 μg nightly, with success rates of 10-65% but high relapse rates up to 80% after discontinuation. 1

Mechanism of Action

• DDAVP is a synthetic analogue of antidiuretic hormone (ADH) vasopressin that decreases urine production at night 1
• It works by increasing water reabsorption in the kidneys, addressing the absence of normal nocturnal increase in ADH levels observed in some enuretic patients 1

Dosing Guidelines

• Oral administration: Start with 0.2 mg tablet before bedtime, with incremental increases up to 0.6 mg if lower dose proves ineffective 1, 2
• Intranasal administration: 10-40 μg (one to four sprays) nightly, though oral formulation is now more commonly used 1, 2
• Duration of action is 10-12 hours, with compensatory polyuria the following day 1
• The lowest effective dose should be determined empirically for each child 1, 3

Treatment Algorithm

1. First-line consideration: Conditioning with a modern, portable, battery-operated alarm is highly effective as first-line treatment with cooperative, motivated families 1
2. DDAVP indications:
   • When conditioning treatment fails or is not feasible 1
   • For short-term use (e.g., when child is going to camp) 1
   • For families where sleeping arrangements or support are not adequate for alarm therapy 1
3. Treatment duration: When effective, continue for 3-4 months before attempting discontinuation 3, 4

Safety Precautions

• Fluid restriction: Limit evening fluid intake to 200 ml (6 ounces) or less with no drinking until morning 2, 5
• Monitoring: Electrolyte monitoring is recommended if intercurrent illness complicates the picture during treatment 1, 5
• Contraindications: Polydipsia (excessive drinking) is a contraindication to DDAVP treatment 2, 5
• Side effects: Water intoxication leading to hyponatremia and seizures is rare but serious 1, 5
• Other side effects include headache, abdominal discomfort, nausea, and nasal congestion, though these are relatively uncommon 1, 6

Efficacy and Outcomes

• Success rates range from 10% to 65% during active treatment 1
• Relapse rates are high (up to 80%) after treatment discontinuation 1, 7
• Only about 24.5% of subjects achieve short-term dryness, and long-term dryness after discontinuation is achieved in approximately 5.7-21% of patients 6
• Children older than 9 years and those with fewer initial wet nights tend to respond better 6
• Low-dose responders are more likely to achieve complete response without needing to increase to maximum doses 3

Combination Therapy

• The combination of DDAVP and a sustained-release anticholinergic agent may be more effective than DDAVP alone in some cases 1
• Switching to alternative treatment (alarm) following partial or no response to DDAVP can provide additional benefit 7

Comparative Efficacy

• Alarm therapy has shown better long-term results compared to DDAVP 6, 7
• DDAVP provides more rapid initial response, while alarm therapy has lower relapse rates 7, 8

DDAVP is an important pharmacological option for nocturnal enuresis, particularly when behavioral approaches are not feasible or have failed, but should be used with appropriate precautions regarding fluid intake and monitoring for hyponatremia, especially during illness.