The efficacy and safety of 6 weeks of treatment with desmopressin tablets at doses of 200 to 400 micrograms.at bedtime were investigated in 33 children with monosymptomatic nocturnal enuresis. During an initial 1 to 2-week dose titration period 22 patients (67%) became either completely dry or showed improvement, 7 (21%) showed no response and 4 (12%) dropped out of therapy. During tablet treatment 17 patients on 400 micrograms.and 5 on 200 micrograms.at bedtime increased the number of weekly dry nights from 2.0 +/- 1.6 (standard deviation) during a 2-week observation period to 5.2 +/- 1.9 (p < 0.001). During a subsequent 2-week period 40 micrograms.intranasal desmopressin showed a similar overall efficacy, with a mean of 5.4 +/- 1.6 dry nights per week. In addition, intranasal treatment was able to increase the number of dry nights in 2 of the 7 nonresponders to tablet treatment.