Clinical study on Bifidobacterium lactis BL-99 assisting to improve functional dyspepsia

Functional dyspepsia (FD) is a common chronic gastrointestinal disorder without known organic pathology changes. Recurrence symptoms and longer duration resulting in poor quality of life and high medical expenses for patients. Therefore, searching for a prolonged treatment of FD has considerable clinical value. This research aims at determining the efficacy of Bifidobacterium lactis BL-99 (BL-99) in improving gut microbiota and promoting digestion in patients with functional dyspepsia, and to determine the dose-effect relationship. In this randomized controlled trial, 300 subjects will be randomized into six group (mild placebo group, mild low dose group, mild high dose group, severe placebo group, severe low dose group, and severe high dose group). Except the mild placebo group, other groups will receive BL-99 and/or proton pump inhibitors (PPI). The efficacy of BL-99 to improve FD symptoms and the underlying mechanism, and the impact of BL-99 on gastrointestinal microbiota after PPI therapy will be evaluated. The clinical trial registry is at Chictr.org.cn ID ChiCTR2000041430.