Herbal Formula Shenling Baizhu San for Chronic Diarrhea in Adults: A Systematic Review and Meta-analysis

Background: Shenling Baizhu San (SBS), a well-known Chinese medicine herbal formula, has been widely used for treating chronic diarrhea for thousands of years. However, the efficacy and safety of SBS in treating chronic diarrhea have not been fully assessed. Objective: This study evaluates the efficacy and safety of the herbal formula SBS in symptomatic relief of chronic diarrhea. Methods: English and Chinese language databases (PubMed, Cochrane Library, China National Knowledge Infrastructure, China Science and Technology Journal Database, Wanfang Data, and SinoMed electronic databases) were searched through April 2020 for relevant randomized controlled trials (RCTs). The outcomes in these RCTs included stool frequency, stool consistency, patient-reported satisfaction of chronic diarrhea treatment, quality of life and adverse events. Paired reviewers independently extracted data and conducted qualitative and quantitative analyses. The Cochrane revised risk of bias RoB-2 tool was applied to assess the risk of bias for each trial whereas the RevMan 5.3 software was used for outcomes data synthesis and meta-analysis. Mean difference (MD) and the 95% confidence interval (CI) were used to measure continuous data. The dichotomous data were analyzed via the relative risk (RR) with 95% CIs. Results: Fourteen RCTs including 1158 participants (54% males) with chronic diarrhea were included. Shenling Baizhu San combined with or without conventional medicine (CM) was associated with greater patient-reported satisfaction than CM alone. There was no increased risk of adverse events (AEs) during treatment. Conclusion: Treatment with SBS was associated with significant improvement in patient-reported satisfaction, irrespective of conventional medicine use. Rigorous and powered RCTs with objective outcome measures are needed to confirm the effects of SBS in specific gastrointestinal disease populations with chronic diarrhea symptoms. Systematic review registration number (PROSPERO): CRD42020178073