A randomized controlled trial of a probiotic combination VSL# 3 and placebo in irritable bowel syndrome with bloating

Aim: To evaluate the effects of a combination probiotic on symptoms and colonic transit in patients with irritable bowel syndrome (IBS) and significant bloating. Methods: Forty-eight patients with Rome II IBS were randomized in a parallel group, double-blind design to placebo or VSL# 3 twice daily (31 patients received 4 weeks and 17 patients 8 weeks of treatment). Pre- and post-treatment colonic transit measurements were performed using scintigraphy with In-111 charcoal. Symptoms were summarized as an average daily score for the entire period of treatment and separately for the first 4 weeks of treatment. Weekly satisfactory relief of abdominal bloating was assessed. Results: Treatment with VSL# 3 was associated with reduced flatulence over the entire treatment period (placebo 39.5 +/- 2.6 vs VSL# 3 29.7 +/- 2.6, P = 0.011); similarly, during the first 4 weeks of treatment, flatulence scores were reduced (placebo 40.1 +/- 2.5 vs VSL# 3 30.8 +/- 2.5, P = 0.014). Proportions of responders for satisfactory relief of bloating, stool-related symptoms, abdominal pain and bloating scores were not different. Colonic transit was retarded with VSL# 3 relative to placebo (colon geometric center 2.27 +/- 0.20 vs 2.83 +/- 0.19, P = 0.05 respectively). Conclusion: VSL# 3 reduces flatulence scores and retards colonic transit without altering bowel function in patients with IBS and bloating.