Bacillus coagulans as a potent intervention for treating irritable bowel syndrome: A systematic review and meta-analysis of randomized control trials

Irritable bowel syndrome (IBS) is the most common functional gastrointestinal tract disorder. Bacillus coagulans (BC) is a potent spore-forming probiotic that has been proposed as a potent supplement that can improve gastrointestinal tract dysbiosis and relieve IBS symptoms. We aim to assess the effect of BC on different IBS symptoms severity among other IBS-related symptoms. We searched seven databases for RCTs that compare the use of BC versus placebo in the management of IBS symptoms. Our search finally retrieved seven RCTs after extensive screening. Our analysis revealed that BC significantly improved the severity of IBS symptoms such as urgency {MD: −1.05, 95% CI: −1.33; −0.77}, bowel habit satisfaction {MD: −1.40, 95% CI: −1.68; −1.13}, straining {MD: −1. 22, 95% CI: −1.61; −0.82}, the passage of gas {MD: −1.25, 95% CI: −1.51; −0.99}, incomplete evacuation {MD: −1.06, 95% CI: −1.55; −0.57}, and the total score of symptom severity {MD: −10.13, 95% CI: −11.61; −8.66, (P < 0.00001)}. We also found a significant improvement in the physician’s global assessment score at 8 weeks {MD: 1.61, 95% CI: 0.61; 2.60, (P = 0.002)}; however, results were not significant at 4 weeks (P = 0.48). Moreover, our results indicate a significant decrease in the discomfort score after 4 and 8 weeks, the bloating score after 2, 4, 8, and 11 weeks and the vomiting score. Regarding abdominal pain, BC significantly lowered pain score after 2, 4, 8, and (11–13) weeks. BC is a very effective probiotic in reducing the severity of IBS symptoms and abdominal pain with no serious adverse events. Future studies are needed to assess the use of BC as a long-term regimen and compare different subspecies of BC.