Irritable bowel syndrome with diarrhoea (IBS-D) is a common functional gastrointestinal disorder that significantly reduces quality of life. Probiotics have the potential to alleviate symptoms of IBS-D. This randomized controlled trial aimed to investigate the efficacy of a probiotic mixture comprising Lacticaseibacillus paracasei Zhang, Bifidobacterium animalis subsp. lactis V9, and Lactiplantibacillus plantarum P8 in managing IBS-D. 110 patients were randomly assigned to receive the probiotics, otilonium bromide, or a combination of probiotics and otilonium bromide (n = 37, 35 and 38, respectively), with a 4-week intervention period, and a 2-week follow-up observation period. The primary outcomes were the percentage of responders on a composite abdominal pain and stool consistency score during at least 2 weeks of the treatment period, and the IBS-symptom severity scale score. Secondary outcome measures were the changes of IBS-quality of life questionnaire, visceral sensitivity index, hospital anxiety and depression scale, intestinal mucosal barrier integrity indicators, and fecal metagenome and metabolome. Both intention-to-treat and per-protocol analyses revealed that the composite response rate in the probiotic group, otilonium bromide group, and the combined treatment group were 45.9%, 42.9%, and 42.1%, respectively (P>0.05). Compared with the baseline, all these three groups significantly improved the IBS symptom severity and the quality of life after 4 weeks of intervention. Moreover, the probiotic treatment enriched specific beneficial intestinal bacteria like Lacticaseibacillus paracasei and Blautia sp., and metabolomics showed increased butyric acid, L-tryptophan, Alpha-linolenic acid, and amino acids levels, with interesting microbe-metabolite correlations such as Lacticaseibacillus paracasei-butyric acid. In conclusion, the results of this study support the use of probiotics in managing IBS-D.
杨妮(YANG NI) (2026) studied this question.