Saccharomyces boulardii and Reduced Diarrhea Rate

Research synthesisModerate evidenceSmall effect4 studies · 4 beneficial · 0 neutral · 0 harmful

Across all 4 studies, Saccharomyces boulardii consistently showed beneficial effects on reducing diarrhea rate, with small to moderate effect sizes. The most robust evidence comes from two randomized controlled trials in children with acute diarrhea and adults with small intestinal bacterial overgrowth, reporting statistically significant reductions in diarrhea duration or resolution. The median study duration was 35 days (reported in 1 study), and doses ranged from not stated to 500 mg twice daily.

Effective dose range: 500 mg twice daily
Studied populations: Children aged 6 months to 5 years with acute diarrhea; patients with small intestinal bacterial overgrowth associated with long-term PPI use

Caveats: Available evidence is overwhelmingly positive — clinical literature in this area is subject to publication bias (null-result studies are less likely to be published or indexed). Evidence base is small (only 4 studies) — conclusions should be considered preliminary.

Generated Jul 10, 2026

Doses used in studies

mg/day: 1,000 (median 1,000, IQR 1,000–1,000) — 1 study

Time to effect

Median: 5 weeks · IQR 5 weeks–5 weeks · Range 5 weeks–5 weeks — Reported in 1 of 4 studies

Safety in these studies

Overall tolerabilityReported
Both probiotics showed improvement in secondary outcomes and were well-tolerated.
from: Randomized, direct comparison study of Saccharomyces boulardii CNCM I-745 versus multi-str
Overall tolerabilityReported
S. boulardii CNCM I-745 being considered a safe probiotic for use in children and adults also finds recommendations in several international guidelines for the management of acute diarrhea.
from: Unique Properties of Yeast Probiotic Saccharomyces boulardii CNCM I-745: A Narrative Revie
Overall tolerabilityReported
Saccharomyces boulardii is one of the best-studied probiotics in acute gastroenteritis (AGE) and is shown to be safe
from: Saccharomyces boulardii CNCM I-745 in different clinical conditions.

4 of 4 papersPopulation:

Randomized, direct comparison study of Saccharomyces boulardii CNCM I-745 versus multi-strained Bacillus clausii probiotics for the treatment of pediatric acute gastroenteritis
- 2022-09-09
- RCT · n = 317
- Medicine 101(36)
- - J. Altcheh
  - Mabel V. Carosella
  - A. Ceballos
  - Ulises D’Andrea
  - Sandra M. Jofre
  - Carolina R. Marotta
  - Domingo Mugeri
  - Liliana Sabbaj
  - A. Soto
  - C. Josse
  - F. Montestruc
  - L. Mcfarland
- PubMed: 36086703
- DOI: 10.1097/MD.0000000000030500
7 Insights on
- Reduced Diarrhea Rate
- High evidence
- Large Human Trial
S boulardii CNCM I-745 showed a significant reduction (P = .04) in the mean duration of diarrhea (64.6 hours, 95% confidence interval [CI] 56.5-72.8) compared to those given B clausii (78.0 hours, 95% CI 69.9-86.1).
Effect
Beneficial
Effect size
Small
Significant
Yes
Dose
not stated
[Study on the efficacy of combination therapy with rifaximin and Saccharomyces boulardii CNCM I-745 in patients with small intestinal bacterial overgrowth associated with long-term use of proton pump inhibitors].
- 2025-08-28
- RCT · n = 108
- Terapevticheskii arkhiv 97(8)
- - I V Maev
  - D N Andreev
  - R I Shaburov
  - A V Zaborovsky
  - A K Fomenko
  - P S Sokolov
  - S V Tsaregorodtsev
  - M K Devkota
  - D T Dicheva
  - S V Cheremushkin
  - N V Cheremushkinа
  - A V Vychkin
- PubMed: 40884341
- DOI: 10.26442/00403660.2025.08.203301
7 Insights on
- Reduced Diarrhea Rate
- High evidence
- Large Human Trial
- Clinical
Statistically significant resolution of diarrhea was observed only in Group 2 (p = 0.033).
Effect
Beneficial
Effect size
Small
Significant
Yes
Dose
500 mg twice daily
Unique Properties of Yeast Probiotic Saccharomyces boulardii CNCM I-745: A Narrative Review.
- 2023-10-01
- Review
- Cureus 15(10)
- - Sarath Gopalan
  - Sridhar Ganapathy
  - Monjori Mitra
  - Neha
  - Devesh Kumar Joshi
  - Krishna C Veligandla
  - Rahul Rathod
  - Bhavesh P Kotak
- PubMed: 37927652
- DOI: 10.7759/cureus.46314
3 Insights on
- Reduced Diarrhea Rate
- Low evidence
In AAD patients, prophylactic use of S. boulardii has shown a significantly lower risk of AAD (in comparison to controls) and restored the diversity of gut microbiota.
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Saccharomyces boulardii CNCM I-745 in different clinical conditions.
- 2014-07-04
- Review
- Expert opinion on biological therapy 14(11)
- - Ener Cagri Dinleyici
  - Ates Kara
  - Metehan Ozen
  - Yvan Vandenplas
- PubMed: 24995675
- DOI: 10.1517/14712598.2014.937419
8 Insights on
- Reduced Diarrhea Rate
- Low evidence
Saccharomyces boulardii is also a recommended probiotic for the prevention of antibiotic-associated diarrhea (AAD), and a recent study showed promising results for the treatment of AAD in children.
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Dose
not specified

Saccharomyces boulardii and Reduced Diarrhea Rate

Randomized, direct comparison study of Saccharomyces boulardii CNCM I-745 versus multi-strained Bacillus clausii probiotics for the treatment of pediatric acute gastroenteritis

[Study on the efficacy of combination therapy with rifaximin and Saccharomyces boulardii CNCM I-745 in patients with small intestinal bacterial overgrowth associated with long-term use of proton pump inhibitors].

Unique Properties of Yeast Probiotic Saccharomyces boulardii CNCM I-745: A Narrative Review.

Saccharomyces boulardii CNCM I-745 in different clinical conditions.