From the Guidelines

Desmopressin (DDAVP) is a viable treatment option for nocturnal enuresis, with reported success rates ranging from 10% to 65%.

DDAVP is a synthetic analogue of the antidiuretic hormone (ADH) vasopressin, which decreases urine production at night when taken at bedtime 1.
It is administered orally in 0.2-mg tablets in doses of 0.2 to 0.6 mg nightly or, less commonly, intranasally as a spray in doses of 10 to 40 μg (one to four sprays) nightly; the lowest effective dose is determined empirically with each child 1.
The combination of DDAVP and a sustained-release anticholinergic agent may be more effective than DDAVP alone 1.

Water intoxication is a rare but serious side effect, and electrolyte monitoring is recommended if intercurrent illness complicates the picture during treatment 1.
Long-term administration of DDAVP has not been associated with depression of endogenous ADH secretion 1.
A history of nasal congestion or sinusitis may impair absorption of the nasal spray form of DDAVP, making the oral form a preferred option 1.

A thorough physical examination and urinalysis are essential in the assessment of enuresis 1.
First-morning specific gravity may be helpful in predicting who will respond to DDAVP treatments 1.
A 2-week baseline record of wet and dry nights is useful in monitoring treatment response 1.

From the Research

Desmopressin has been shown to be effective in treating nocturnal enuresis, with studies demonstrating a significant reduction in the number of wet nights per week 2, 3, 4.
The optimal dosage of desmopressin for treating nocturnal enuresis has been found to be 400 micrograms, with a significant reduction in wet nights observed compared to placebo 2.
Desmopressin treatment has been found to be safe and effective in the long-term, with no significant weight gain due to water retention observed 2.
The response to desmopressin treatment has been found to be similar in patients with concentrated and unconcentrated first morning urine, suggesting that desmopressin may be a feasible option for treating nocturnal enuresis with concentrated first morning urine 3.
To maximize the chances of treatment success with desmopressin, factors such as formulation, dose, timing of administration, food and fluid intake, inter-individual variation in response, body weight, adherence, withdrawal strategies, and combination therapies should be considered 4.

Desmopressin has been found to have a good clinical efficacy in terms of number of nocturnal voids, voided volume, and sleep period, with a minimum dosage of 25 μg orally disintegrating sublingual desmopressin appearing to be ideal for women, and 50 μg for men 5.
Hyponatremia remains a major concern with desmopressin treatment, particularly in patients over 65 years of age, and long-term data on desmopressin remains scarce 5.
Desmopressin has been found to be a safe and effective treatment for nocturnal enuresis, with the oral lyophilisate (MELT) formulation representing a first-line and safe treatment option due to its higher bioavailability and lower doses required 6.