Glucomannan is not effective for the treatment of functional constipation in children: A double-blind, placebo-controlled, randomized trial

Abstract

Treatment measures for constipation in children are often not satisfactory. The aim was to assess the efficacy of glucomannan (GNN) as a sole treatment for functional constipation. Children aged 3-16 years with functional constipation according to Rome III criteria were randomly assigned to receive GNN (2.52g/d) or placebo for 4 weeks. Of the 80 children, 72 (90%) completed the study. The primary outcome, treatment success (≥3 stools per week with no soiling), was similar in the GNN (n=36) and placebo (n=36) groups (relative risk 0.95, 95% CI 0.6 to 1.4). In the GNN group, the stool consistency score was higher at week 1 (P<0.0001), lower at week 3 (P=0.008), and similar at weeks 2 and 4. Stool frequency was higher only at week 3 (P=0.007). Abdominal pain episodes were more frequent in the GNN group at week 1 (P=0.04) and week 4 (P<0.0001) but were similar between groups at weeks 2 and 3. No difference was observed in the frequency of any other secondary outcome or adverse event. In our setting, GNN, as dosed in this study, was not more effective than placebo in achieving therapeutic success in constipated children. The trial was registered at ClinicalTrials.gov (http://clinicaltrials.gov), number NCT01151878.