Functional Bowel Disorder

This is a prospective observational study collecting long-term clinical data and samples for research in pediatric inflammatory bowel disease (IBD) patients with gut inflammation and a control cohort of pediatric patients with disorders of the brain-gut interactions (DBGI) with no detectable gut inflammation.

This randomized, double-blind, placebo-controlled trial will evaluate whether a 14-day course of rifaximin improves bloating in adult patients with Rome IV functional bowel disorders in whom bloating is the predominant symptom. Eligible participants with irritable bowel syndrome, functional constipation, or functional abdominal bloating/distension and bothersome bloating despite adequate bowel movement management will be assigned in a 1:1 ratio to rifaximin 550 mg three times daily or matching placebo for 2 weeks. The primary endpoint is the proportion of participants with bloating response, defined as at least a 1-point reduction from baseline in a 7-point Likert bloating score at the end of treatment.