People mainly take Saccharomyces Boulardii for digestion. Based on 8 first-hand reports and 62 meta-analyses & systematic reviews in the medical literature. Ranked #1920 of 2,750 overall.
Of reports that state an outcome, 50% are positive.
Of the people who reported each effect, the share who said it got better.
Systematic reviews and meta-analyses from PubMed, with their published conclusions.
3+ meta-analyses or systematic reviews and 10+ randomized controlled trials in humans. The grade measures how much human research exists — read the conclusions below for what it found.
Conclusion: The use of S. boulardii as a therapeutic probiotic is evidence-based for both efficacy and safety for several types of diarrhea.
PubMed 20458757 ↗Conclusion: Probiotics probably make little or no difference to the number of people who have diarrhoea lasting 48 hours or longer, and we are uncertain whether probiotics reduce the duration of diarrhoea. This analysis is based on large trials with low risk of bias.
PubMed 33295643 ↗Conclusion: If the use of probiotics for preventing Clostridium difficile-associated diarrhea is considered, the WG suggests using S boulardii (low QoE, conditional recommendation). Other strains or combinations of strains have been tested, but sufficient evidence is still lacking.
PubMed 26756877 ↗Conclusion: However, more clinical outcomes are required on particular strains to confirm the decolonization of the pathogens. Protocol registration: PROSPERO (ID = CRD42021276045).
PubMed 38778521 ↗As stated by users — not a recommendation. Follow the label or your doctor.
How often each side effect came up across all reports.
Verbatim quotes, shortened only — each links to the original discussion.
“Jarrow S. Boulardii Probiotics”
“Saccharomyces Boulardi, 8 Billion/d - probiotic, histamine, gut health”
“Probiotic S. Boulardii: Pathogen-fighting yeast.”
“Get some S.Bouldarri(sp) probiotics if you’re experiencing any diarrhea. Stuff works better than pepto and just as fast.”
“Also tudca, high quality lactobacillus strains, saccharomyces boulardi...”
User data from public discussions; research from PubMed. Information only, not medical advice — talk to a doctor before starting, stopping or combining anything. Data updated October 3, 2026. How we rate