Weaning strategies for osmotic laxatives in children with functional constipation: a pilot multicenter randomized controlled trial.

Background: Long-term maintenance of laxatives is crucial for treating functional constipation (FC) in children. This study aimed to compare the success rates of discontinuation based on different drug reduction methods, in order to identify the optimal strategy for discontinuing laxative use.

Methods: This open-label randomized controlled trial was conducted from September 2020 to September 2021. Children with FC who had been successfully treated with lactulose for more than three months were included. Patients were randomly assigned to one of two groups: dose reduction or frequency reduction over a three-month period. The primary outcome was the weaning success rate at week 12. Participants were divided into two subgroups based on the pre-weaning lactulose dosage: the low-dose group (≤1.5 g/kg/day) and the high-dose group (>1.5 g/kg/day).

Results: A total of 16 patients were enrolled, with a median age of 43 months and 11 boys. There were no significant differences in baseline characteristics between the two groups. The primary outcome showed no significant difference: 66.7% for dose reduction vs. 57.1%. for frequency reduction. Weaning success rates decreased at week 16 (33.3% vs. 57.1%) and week 24 (33.3% vs. 42.9%) without significant differences. In the subgroup analysis, the high-dose group showed a significantly higher weaning success rate at 12 weeks compared to the low-dose group (81.8% vs. 20%, P=0.04). Other measures, including median defecation frequency, incontinence episodes, stool consistency, painful defecations, and compliance, were also similar between the groups. Patient satisfaction was 77.8% for dose reduction and 57.1% for frequency reduction, with no significant difference.

Conclusions: The method of reducing the dose or frequency of lactulose did not affect the weaning success rate in children with FC. However, a pre-weaning lactulose dose exceeding 1.5 g/kg/day may lead to better outcomes at week 12. Despite gradual reduction over more than 3 months, the weaning success rate remained low, highlighting the importance of careful drug discontinuation and follow-up.

Trial registration: The Clinical Research Information Service of the Korea Center for Disease Control and Prevention (https://cris.nih.go.kr/cris, registration No. KCT0006286).