Saccharomyces Boulardii
Probiotic ·Exploratory record · not publication-reviewed ·Updated July 13, 2026
Beneficial probiotic yeast resistant to antibiotics, ideal for gut support during antibiotic use.
Exploratory record, not a reviewed medical publication.
See the editorial and medical-review policies for the publication gate.
This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.
What the research says.
A quick, data-only summary. The full evidence, dosing, and sources are below.
Saccharomyces Boulardii is a probiotic most often used for antibiotic-associated diarrhea, c. difficile prevention, traveler's diarrhea. NutriStack rates the overall evidence as strong. A typical adult dose is 250-500 mg 1-2x daily, commonly taken as saccharomyces boulardii cncm i-745. This profile indexes 18 sources.
The bottom line
Evidence rating strong. Most-documented uses: antibiotic-associated diarrhea, c. difficile prevention, traveler's diarrhea. 18 sources indexed (1993–2025), with 0 interaction records on file.
How it works, mechanistically.
Core mechanism
Yeast-based probiotic that survives antibiotics. Secretes proteases that degrade Clostridium difficile toxins A and B. Stimulates secretory IgA and anti-inflammatory IL-10.18,9
Dosing & protocol.
What it actually costs.
Real-world pricing across three quality tiers. Assumes Saccharomyces boulardii CNCM I-745.
Assumes 250-500 mg 1-2 times daily. Vendor basis: Florastor/iHerb, Vitacost, NOW, and Amazon marketplace; CNCM I-745 branded products price higher. Updated 2026-05-28.
The same dose, as food.
How much you'd eat to match a supplemental dose.
S. boulardii is a specific probiotic yeast strain; ordinary fermented foods do not reliably contain labeled therapeutic amounts.
Full safety detail.
Sources, by evidence tier.
Numbered references. Citations throughout the page link here.
Meta-analyses & systematic reviews
9- 1Efficacy and safety of Saccharomyces boulardii CNCM I-745 for the treatment of pediatric acute diarrhea in China: a systematic review and meta-analysisPMIDMcFarland LV, Li T · Frontiers in cellular and infection microbiology · 2025
McFarland LV, Li T. Efficacy and safety of Saccharomyces boulardii CNCM I-745 for the treatment of pediatric acute diarrhea in China: a systematic review and meta-analysis. Frontiers in cellular and infection microbiology. 2025
- 2Systematic review with meta-analysis: Saccharomyces boulardii in the prevention of antibiotic-associated diarrhoeaPMIDSzajewska H et al. · Aliment Pharmacol Ther · 2015
S. boulardii reduced risk of antibiotic-associated diarrhea from 18.7% to 8.5% (RR: 0.47; 95% CI: 0.38-0.57) across 21 RCTs with 4,780 participants
- 3Systematic review with meta-analysis: Saccharomyces boulardii supplementation and eradication of Helicobacter pylori infectionPMIDSzajewska H, Horvath A, Kołodziej M · Alimentary pharmacology & therapeutics · 2015
Szajewska H, Horvath A, Kołodziej M. Systematic review with meta-analysis: Saccharomyces boulardii supplementation and eradication of Helicobacter pylori infection. Alimentary pharmacology & therapeutics. 2015
- 4Systematic review and meta-analysis of Saccharomyces boulardii in adult patientsPMIDMcFarland LV · World J Gastroenterol · 2010
S. boulardii can be strongly recommended for prevention of antibiotic-associated diarrhea and traveler's diarrhea in adults, and shows promise for IBD
- 5Meta-analysis: the effects of Saccharomyces boulardii supplementation on Helicobacter pylori eradication rates and side effects during treatmentPMIDSzajewska H, Horvath A, Piwowarczyk A · Alimentary pharmacology & therapeutics · 2010
Szajewska H, Horvath A, Piwowarczyk A. Meta-analysis: the effects of Saccharomyces boulardii supplementation on Helicobacter pylori eradication rates and side effects during treatment. Alimentary pharmacology & therapeutics. 2010
- 6Saccharomyces boulardii in the prevention of antibiotic-associated diarrhea: a meta-analysisSource linkedPMIDMcFarland LV · Int J Probiotics Prebiotics · 2010
- 7Prevention of Clostridium difficile infection with Saccharomyces boulardii: a systematic reviewPMIDTung JM, Dolovich LR, Lee CH · Canadian journal of gastroenterology = Journal canadien de gastroenterologie · 2009
Tung JM, Dolovich LR, Lee CH. Prevention of Clostridium difficile infection with Saccharomyces boulardii: a systematic review. Canadian journal of gastroenterology = Journal canadien de gastroenterologie. 2009
- 8Meta-analysis: Saccharomyces boulardii for treating acute diarrhoea in childrenPMIDSzajewska H, Skórka A, Dylag M · Alimentary pharmacology & therapeutics · 2007
Szajewska H, Skórka A, Dylag M. Meta-analysis: Saccharomyces boulardii for treating acute diarrhoea in children. Alimentary pharmacology & therapeutics. 2007
- 9Meta-analysis of probiotics for the prevention of antibiotic associated diarrhea and the treatment of Clostridium difficile diseasePMIDMcFarland LV · Am J Gastroenterol · 2006
S. boulardii and Lactobacillus showed strongest evidence for preventing AAD; S. boulardii effective for preventing C. difficile recurrence
Randomized controlled trials
4- 10Efficacy and safety of Saccharomyces boulardii as adjunct therapy with Vancomycin in treating Clostridioides difficile infection: A randomized controlled trialPMIDChitapanarux T, Wiracha U, Winichakoon P et al. · Scientific reports · 2025
Chitapanarux T, Wiracha U, Winichakoon P et al.. Efficacy and safety of Saccharomyces boulardii as adjunct therapy with Vancomycin in treating Clostridioides difficile infection: A randomized controlled trial. Scientific reports. 2025
- 11A Randomized, Controlled Study Evaluating Effects of Saccharomyces boulardii in Adult Patients with AsthmaPMIDDezfouli KA, Darban M, Hemmati M et al. · Drug research · 2025
Dezfouli KA, Darban M, Hemmati M et al.. A Randomized, Controlled Study Evaluating Effects of Saccharomyces boulardii in Adult Patients with Asthma. Drug research. 2025
- 12A randomized placebo-controlled trial of Saccharomyces boulardii in combination with standard antibiotics for Clostridium difficile diseasePMIDMcFarland LV et al. · JAMA · 1994
Patients treated with S. boulardii and standard antibiotics had significantly lower relative risk of C. difficile disease recurrence (RR 0.43; 95% CI: 0.20-0.97)
- 13Prevention of traveler's diarrhea with Saccharomyces boulardii. Results of a placebo controlled double-blind studyPMIDKollaritsch H et al. · Fortschr Med · 1993
Double-blind placebo-controlled study confirmed S. boulardii effectiveness in preventing traveler's diarrhea
Reviews & position papers
1- 14Effectiveness and safety of Saccharomyces boulardii for acute infectious diarrheaPMIDDinleyici EC et al. · Expert Opin Biol Ther · 2012
Strong evidence that S. boulardii is safe and has clinically significant benefit in treating acute infectious diarrhea regardless of cause
Observational studies
1- 15Seven cases of fungemia with Saccharomyces boulardii in critically ill patientsPMIDLherm T, Monet C, Nougiere B et al. · Intensive Care Medicine · 2002
Case series documents S. boulardii fungemia in critically ill patients, supporting ICU and catheter cautions.
Reference material
3- 16Saccharomyces cerevisiae fungemia: Risk factors, outcome and links with S. boulardii-containing probiotic administrationPMIDPoncelet A, Ruelle L, Konopnicki D et al. · Infectious Diseases Now · 2021
Observational evidence links S. cerevisiae fungemia risk factors with S. boulardii-containing probiotic administration.
- 17Li M, Xie Y. Efficacy and safety of Saccharomyces boulardii as an adjuvant therapy for the eradication of Helicobacter pylori: a meta-analysis. Frontiers in cellular and infection microbiology. 2025Source linkedPMID
- 18Waitzberg D, Guarner F, Hojsak I et al.. Can the Evidence-Based Use of Probiotics (Notably Saccharomyces boulardii CNCM I-745 and Lactobacillus rhamnosus GG) Mitigate the Clinical Effects of Antibiotic-Associated Dysbiosis?. Advances in therapy. 2024Source linkedPMID
Common questions.
Quick answers about Saccharomyces Boulardii, drawn from the data on this page.
What is Saccharomyces Boulardii?
Beneficial probiotic yeast resistant to antibiotics, ideal for gut support during antibiotic use.
What is Saccharomyces Boulardii used for?
Commonly cited benefits of Saccharomyces Boulardii include: Antibiotic-associated diarrhea; C. difficile prevention; Traveler's diarrhea; IBD support. NutriStack rates the overall evidence as strong.
What is a typical dose of Saccharomyces Boulardii?
A typical adult dose of Saccharomyces Boulardii is 250-500 mg 1-2x daily. The commonly recommended form is Saccharomyces boulardii CNCM I-745. These are general ranges, not personalized advice; confirm the right dose with a clinician.
What are the side effects of Saccharomyces Boulardii?
Reported side effects include gas, bloating, very rarely fungemia in severely immunocompromised. This is educational information; check with a healthcare professional before use.
How strong is the evidence for Saccharomyces Boulardii?
NutriStack rates this as Strong, meaning multiple high-quality meta-analyses or systematic reviews converge on the same finding. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.
Use this with your stack
Saccharomyces Boulardii in NutriStack.
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