A randomized controlled trial of a probiotic, VSL#3, on gut transit and symptoms in diarrhoea-predominant irritable bowel syndrome.
Level 2 - randomized trial
Individual randomized controlled trial
PubMed 12656692 · doi:10.1046/j.1365-2036.2003.01543.x
What was done
Twenty-five patients with Rome II diarrhoea-predominant irritable bowel syndrome (IBS-D) were randomly assigned to receive VSL#3 powder (450 billion lyophilized bacteria/day) or matching placebo twice daily for 8 weeks after a 2-week run-in. Pre- and post-treatment gastrointestinal transit measurements were obtained. Patients logged daily diary entries recording bowel function and symptoms (abdominal bloating, pain, gas, urgency, and global symptom relief) across the 10-week study period.
What was found
No statistically significant differences occurred between VSL#3 and placebo for mean gastrointestinal transit measurements, bowel function scores, or satisfactory global symptom relief pre- or post-therapy. The between-group difference in abdominal bloating scores was borderline significant (P = 0.09). Within-group analysis showed a significant reduction in abdominal bloating in the VSL#3 arm (mean post- minus pre-treatment score: -13.7; 95% CI, -2.5 to -24.9; P = 0.046), but not in the placebo arm (mean change: -1.7; 95% CI, 7.1 to -10.4; P = 0.54). VSL#3 had no significant effect on abdominal pain, gas, or urgency.
Why it matters
This trial suggests that any symptom improvement from VSL#3 in diarrhoea-predominant IBS, particularly for abdominal bloating, occurs without measurable alteration of colonic or gastrointestinal transit.
Limits
The study evaluated a very small cohort (n = 25) powered only to detect a large (50%) change in colonic transit. Primary transit and global symptom endpoints were negative. The positive bloating signal relies on within-group changes after between-group comparisons failed to reach statistical significance (P = 0.09). Duration was limited to 8 weeks of treatment.
Cited by
- supports VSL#3 probiotic sachets contain 450 billion CFU, which is approximately 10 times higher than what most probiotic supplements contain.