Ramosetron for the treatment of irritable bowel syndrome with diarrhea: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND: Ramosetron is a potent and selective serotonin type 3 receptor antagonist. This meta-analysis aimed to analyze the efficacy and safety of ramosetron for irritable bowel syndrome with diarrhea (IBS-D). METHODS: Pubmed, MEDLINE, EMBASE and the Cochrane Library were searched for randomized controlled trials investigating the efficacy and safety of ramosetron for IBS-D. Risk of bias was assessed as described in the Cochrane handbook. A random effects model was used to calculate the effects of ramosetron vs placebo on symptomatic improvements, including relief of overall IBS symptoms, relief of abdominal discomfort/pain, improvement in abnormal bowel habits, and improvement in stool consistency, expressed as pooled relative risks (RRs) with 95% confidence interval (CI). Adverse events data were also summarized with RRs. RESULTS: Four randomized controlled trials involving 1623 participants were included. Compared with placebo, ramosetron could lead to relief of overall IBS symptoms (RR 1.70; 95%CI 1.48, 1.95), relief of abdominal discomfort/pain (RR 1.41; 95%CI, 1.24, 1.59), improvement in abnormal bowel habits (RR 1.72; 95%CI, 1.50, 1.98) and improvement in stool consistency (RR 1.71; 95%CI 1.40, 2.08). Ramosetron could lead to relief of overall IBS symptoms in both male and female patients (RR; 95%CI: 1.94; 1.58, 2.38 and 1.49; 1.25, 1.79). The RR (95%CI) for reported adverse events of ramosetron vs placebo was 1.10 (0.97, 1.26) across all studies. No serious adverse events (e.g., ischemic colitis) were reported. The incidences of hard stool and constipation were higher in ramosetron group compared with placebo group (RR; 95%CI: 4.74; 3.00, 7.51 and 2.53; 1.57, 4.10, respectively). CONCLUSIONS: Ramosetron had beneficial effects to both male and female IBS-D patients. Treatment with ramosetron could cause more hard stool and constipation, without severe adverse events.