A comparison of amitriptyline, vasopressin and amitriptyline with vasopressin in nocturnal enuresis

Abstract

Forty-five children aged 6–14 years with primary nocturnal enuresis were randomised to determine whether desmopressin is more effective than amitriptyline and whether the combination of amitriptyline/desmopressin is more effective than amitriptyline or desmopressin alone. Amitriptyline dosage was 25 mg for children 6–10 years and 50 mg for children aged 10–14 years. Desmopressin (20 μg) was given in the same dosage for all age groups. After a run-in period of 2 weeks, children were treated for 16 weeks and then observed for 12 weeks. In the amitriptyline group mean wet nights per week decreased from 5.8±0.9 to 3.3±1.9 (P<0.0005); in the desmopressin group mean wet nights per week decreased from 6.0±0.9 to 4.7±1.7 (P<0.02); in the amitriptyline/desmopressin group mean wet nights per week decreased from 6.3±0.9 to 3.3±2.5 (P<0.0006). When comparing the groups, amitriptyline/desmopressin and amitriptyline were statistically more effective than demopressin in week 6 (P<0.009), week 8 (P<0.03) and week 10 (P<0.04). No significant side effects occurred. At this dose amitriptyline was more effective than desmopressin and the combination of desmopressin and amitriptyline did not confer any additional benefit.