Herbal medicine in the treatment of functional gastrointestinal disorders: A systematic review with meta-analysis.

Abstract

The efficacy of herbal medicines (HMs) for functional gastrointestinal disorders (FGIDs) including irritable bowel syndrome (IBS), functional dyspepsia (FD) and functional constipation (FC) is controversial. A systematic review with meta-analysis was conducted to determine their effectiveness for FGIDs. We searched the following electronic databases till July 2019 with English language restriction: The Cochrane Library, EMBASE and PUBMED. Randomized double-blind controlled trials of HMs compared with placebo or conventional pharmacological drugs for adult FGIDs patients were included. In total, 49 trials involving 7396 participants with FGIDs were included. The risk of bias was low in 9, unclear in 36, and high in 4 trials. More than 33 different herbal formulae were tested. HMs demonstrated statistically significant benefits for symptom improvement compared with placebo in 46 trials (RR=1.67, 95% CI 1.48-1.88). When compared with conventional pharmacological therapy in 5 trials, HMs were found to be non-inferior (RR=1.10, 95% CI 1.03-1.18). The number of trials with regards to FD, IBS and FC were 19, 23 and 7 respectively. Subgroup analysis found that HMs were better than placebo in alleviating symptoms for FD (RR=1.50, 95% CI 1.32-1.69), IBS (RR=1.62, 95% CI 1.32-1.97) and FC (RR=3.83, 95% CI 2.26-6.50). HMs tended to have more patients with adverse events than placebo, but similar to conventional pharmacological drugs. Our findings provide a positive signal for HMs as a potentially well-tolerated and effective treatment for FGIDs, deserving further examination in high-quality trials.