Efficacy of polyethylene glycol 3350 as compared to lactulose in treatment of ROME IV criteria-defined pediatric functional constipation: A randomized controlled trial

Background and Aims Functional constipation is a common childhood problem, with a prevalence of approximately 3% worldwide. The aim of the study was to compare the efficacy of polyethylene glycol (PEG) 3350 and lactulose in the treatment of pediatric functional constipation. Methods A total of 100 subjects with functional constipation were enrolled and centrally randomized to receive PEG 3350 (0.7-1.5 mg/kg/day) or lactulose (0.7-2.0 g/kg/day). Results There was a significant increase in median (min, max) stool frequency within 1 week in the PEG 3350 group as compared to the lactulose group (1 [0, 3] to 8 [3, 39] vs. 1 [0, 3] to 7 [1, 17]) (p-value < 0.01). The trend was maintained at week 2, week 3 (p-value < 0.01), and week 4 (p-value = 0.05) with the PEG 3350 group reporting higher weekly median stool frequency than the lactulose group. The PEG group reported significant reduction in painful bowel movements from 68.8% subjects at baseline to 43.8% at the end of first week, whereas the lactulose group reported an increase from 48.9% to 73.3% (p-value = 0.05). Other parameters of constipation, i.e. straining, large diameter stool, and large fecal mass as reported subjectively by parents, significantly decreased from baseline to the end of the study in the PEG 3350 arm compared to those in the lactulose arm. At the end of week 4, there was a statistically significant reduction in all the ROME IV-defined criteria between the two groups. Conclusion This study proved that the PEG 3350 treatment group had early symptom relief and significant improvement compared to the lactulose group in pediatric functional constipation.