Saccharomyces boulardii
S. boulardii CNCM I-745 · The Probiotic Yeast
Evidence grade 4 of 5, Strong. Read how the Atlas grades evidence.
For prevention of antibiotic-associated diarrhea (AAD), the evidence is strong and reaches grade 4: McFarland's 2010 meta-analysis pooled 10 RCTs, 8 of them significant, for a relative risk of 0.47 (95% CI 0.35 to 0.63) and a number-needed-to-treat of about 10. Cochrane pediatric probiotic reviews lean heavily on S. boulardii CNCM I-745 arms, and China-based systematic reviews report AAD risk reductions near 51 to 57 percent. Other uses grade lower and are not the headline: C. difficile recurrence rests on 2 small RCTs where benefit was seen mainly alongside high-dose vancomycin (grade 3), primary CDI prevention has been null in pooled analysis, and traveler's diarrhea evidence comes from a small number of arms with a modest RR near 0.85 (grade 2 to 3). The overall entry grade of 4 is anchored to the AAD indication, with the rest labeled honestly as moderate or preliminary.
- FDA
- Legal supplement (DSHEA); Rx in some European countries
- WADA
- Not prohibited
Reference only. Not medical advice.
What can go wrong
Very well tolerated in healthy users, but a documented cause of fungemia in critically ill, immunocompromised, and central-line patients, where it is contraindicated; capsules must not be opened near central venous catheters.
Saccharomyces boulardii is a probiotic yeast, not a bacterium, which is much of what makes it distinctive. A French scientist, Henri Boulard, first isolated it in the 1920s from lychee and mangosteen skins in Indochina after noticing local people chewing the peels during cholera outbreaks. The best-studied preparation is the CNCM I-745 strain (sold as Florastor and, in parts of Europe, as a registered drug). Its strongest evidence is for preventing antibiotic-associated diarrhea, where meta-analysis puts the relative risk near 0.47. Because it is a yeast, it survives antibiotics that would kill bacterial probiotics and does not need refrigeration, but that same biology carries a real, documented downside: bloodstream infection in critically ill and immunocompromised patients.
The probiotic yeast, antibiotic-resistant, heat-stable, and the cleanest C. diff evidence in the category.
What people take it for
What it is taken for. Approval, where it exists, covers only some of these.
How it works
Saccharomyces boulardii is a probiotic yeast, not a bacterium, making it mechanistically distinct from every Lactobacillus and Bifidobacterium strain on the market. The CNCM I-745 strain (Florastor commercial form) is a tropical yeast originally isolated by Henri Boulard in 1923 from lychee and mangosteen fruit during a cholera outbreak in Indochina. Three biological properties give S. boulardii its unique clinical position: it cannot permanently colonize the human gut (transient passage in days to weeks), it is inherently antibiotic-resistant (survives concurrent antibiotic therapy), and it is heat-stable (does not require refrigeration). The transient colonization is mechanistically why discontinuation does not produce dysbiosis, there is nothing to lose because nothing settled in. The clinical mechanisms operate through several pathways simultaneously. S. boulardii binds and neutralizes Clostridioides difficile toxins A and B directly through cell-wall protein interactions, reducing toxin-mediated colonic injury. It produces a 54 kDa serine protease that degrades C. difficile toxin A. It competitively inhibits bacterial adhesion to enterocytes, reducing colonization by pathogenic E. coli, Salmonella, and Shigella. It stimulates intestinal IgA secretion and modulates innate immune responses through TLR pathways. It enhances disaccharidase activity in enterocytes (lactase, sucrase, maltase), improving carbohydrate digestion during diarrheal illness. The combined mechanism, anti-toxin, anti-adhesion, immunomodulatory, and digestive-support, explains why S. boulardii has efficacy across multiple distinct diarrheal indications rather than being confined to a single mechanism-specific use case.
How it is taken
The standard adult dose is 250mg (5 billion CFU) twice daily, the dose used in essentially all positive AAD prevention trials. For recurrent C. difficile, doses double to 500mg twice daily during and 4-8 weeks after standard antimicrobial therapy. Take with or without food, absorption pharmacology does not apply because S. boulardii is not absorbed; it passes through the gut transiently. Critically, S. boulardii can be taken concurrently with antibiotics because it is inherently antibiotic-resistant, this is the major mechanistic advantage over bacterial probiotics, which the antibiotic kills. Heat stability means the product does not require refrigeration, simplifying travel and storage. Discontinuation does not require tapering, the yeast clears within days. Effects accumulate during use; the prophylactic AAD indication requires continuous dosing through the antibiotic course and 1-2 weeks beyond.
- Standard adult
- 250mg twice daily (5B CFU each)
- Recurrent C. difficile
- 500mg twice daily during and 4-8 weeks after antimicrobials
- Pediatric acute diarrhea
- 250mg twice daily for 5-7 days
- Traveler's diarrhea
- 250mg twice daily during travel
- Concurrent antibiotics
- Yes, S. boulardii is antibiotic-resistant
- Refrigeration
- Not required, heat stable
- Food state
- With or without food; not absorbed
- Discontinuation
- No taper needed; clears in days
Which form to buy
Not all preparations of the same ingredient are the same thing, and the trials were run on particular ones.
Florastor® (S. boulardii CNCM I-745)
The most-clinically-studied commercial form, marketed in the US by Biocodex. CNCM I-745 strain identifier, the form used in essentially all major modern S. boulardii trials. Each capsule contains 250mg (5 billion CFU). Heat-stable, antibiotic-resistant. The reference standard for the category.
Yomogi® / Perenterol® (CBS 5926)
European brands using a closely-related S. boulardii strain (CBS 5926). Substantially overlapping clinical evidence with CNCM I-745. Marketed throughout Europe by Sanofi and licensees. Functionally equivalent for most indications.
Generic S. boulardii Supplements
Many mass-market supplements label "Saccharomyces boulardii" without strain identifier. The unspecified strain may be the same as CNCM I-745 or may be different. Without strain specification, the trial evidence does not directly transfer. Verify strain identifier on label.
High-Dose Pharmaceutical (500mg-1g)
Pharmaceutical-grade higher-dose preparations for specific clinical indications (recurrent C. difficile, severe AAD prevention during high-risk antibiotic therapy). Specialist guidance for dosing above standard 500mg/day.
S. boulardii + Lactobacillus Combination
Combination products pairing S. boulardii with bacterial probiotics. Mechanistically complementary (different mechanisms, different strain biology). The combination evidence is generally derived from individual-strain trials rather than direct comparison trials.
S. boulardii Sachets (Powder)
Powder sachets for pediatric and adult patients with swallowing difficulty or for higher-dose protocols. Same active strain; different administration format. Often used in pediatric acute diarrhea protocols.
Bulk Powder (Veterinary or Compounding)
Bulk S. boulardii powder for compounding or veterinary use. Quality and strain identification often poor. Not appropriate for human clinical use outside specifically-verified pharmaceutical compounding.
Who it works for, and who it does not
Patients starting broad-spectrum antibiotics
The strongest evidence-base indication. McFarland 2006 and subsequent meta-analyses support ~50% reduction in antibiotic-associated diarrhea with prophylactic S. boulardii throughout antibiotic course and 1-2 weeks after. Concurrent administration is fine because S. boulardii is antibiotic-resistant.
Recurrent C. difficile infection
Surawicz 2000 and subsequent trials support S. boulardii adjunct to standard vancomycin/metronidazole/fidaxomicin therapy for recurrence prevention. Specialty gastroenterology recognizes this as evidence-supported adjunct. Coordinate with infectious disease.
Acute pediatric infectious diarrhea
Vandenplas 2009 and multiple replication trials support ~1-day reduction in diarrhea duration in pediatric acute gastroenteritis. Reasonable adjunct to oral rehydration in viral gastroenteritis.
Traveler's diarrhea prevention
Prophylactic use during travel to high-risk destinations shows modest reduction in TD incidence. Not a substitute for standard food/water precautions. Reasonable adjunct for high-risk travelers (Mexico, India, Southeast Asia, parts of Africa).
H. pylori eradication therapy
Szajewska 2010 meta-analysis supports S. boulardii adjunct to standard triple/quadruple therapy, improves eradication rates and reduces therapy-related GI side effects. Coordinate with gastroenterology.
Inflammatory bowel disease adjunct
Preliminary evidence for Crohn's maintenance (Plein 2003) and ulcerative colitis (multiple smaller trials). Not yet routine guideline therapy. Reasonable adjunct under gastroenterology guidance.
Severely immunocompromised patients
Real safety concern, fungemia case reports in patients with central venous catheters, ICU patients, post-transplant immunosuppression, and severe neutropenia. Generally avoided in these populations or used with specific protocols.
Healthy adults for daily routine
Less compelling case than other probiotics for daily wellness use. S. boulardii's strengths are specific diarrheal indications rather than general gut health. Lactobacillus and Bifidobacterium strains are typically more cost-effective for daily wellness.
Taken with other things
Combinations people actually use. Evidence for one ingredient is not evidence for a pair.
Antibiotic therapy
The signature indication. S. boulardii is antibiotic-resistant and can be taken concurrently with all major antibiotic classes, substantially different from Lactobacillus and Bifidobacterium probiotics, which the antibiotic kills. Co-administration throughout the antibiotic course and 1-2 weeks beyond.
Lactobacillus rhamnosus GG (LGG)
Different mechanism (yeast versus bacterium) and complementary clinical evidence. Common AAD prevention combination, particularly in pediatric protocols. Mechanistically distinct anti-diarrheal pathways.
C. difficile antimicrobial therapy
Vancomycin, metronidazole, fidaxomicin co-administration with S. boulardii for recurrent C. difficile is evidence-supported. The antimicrobial clears active infection; S. boulardii reduces recurrence risk.
H. pylori eradication therapy
Adjunct to standard triple or quadruple therapy. Improves eradication rates and reduces therapy-related GI side effects. Coordinate with gastroenterology.
Standard probiotics (Bifidobacterium, Lactobacillus)
Different mechanisms allow co-administration without interference. Often combined in multi-strain formulations.
Antifungal medications
Antifungals (fluconazole, nystatin, others) actively kill S. boulardii, directly counterproductive co-administration. Pause S. boulardii during antifungal therapy.
Central venous catheters / ICU
Documented case reports of catheter contamination and fungemia. Do NOT open S. boulardii capsules in patient rooms or on hospital surfaces in CVC patients. Many hospitals have formal policies against S. boulardii in ICU.
Severe immunocompromise
Real fungemia risk in post-transplant, severe neutropenia, advanced HIV, and other severely immunocompromised states. Generally avoid; specialist guidance if specific indication.
Active candidiasis
S. boulardii is a different yeast from Candida and does not cause candidiasis. However, in users with active invasive candidiasis on antifungal therapy, the antifungal will also kill S. boulardii, making concurrent use ineffective.
What to look for on the label
Look for: explicit strain identifier on the label (CNCM I-745 or CBS 5926); CFU disclosure per dose (typically 5 billion CFU per 250mg capsule); pharmaceutical-grade manufacturing (Biocodex, Sanofi); reputable brand with extensive clinical evidence; heat-stable formulation (no refrigeration required is a quality signal). Avoid: generic "Saccharomyces boulardii" without strain identifier; products without CFU disclosure; suspiciously cheap formulations; combination products that obscure individual S. boulardii dose; refrigerated S. boulardii (suggests non-pharmaceutical-grade manufacturing process).
Safety in detail
- Fungemia is the major documented safety concern, case reports primarily in ICU patients with central venous catheters, post-transplant immunosuppression, and severely immunocompromised hosts. The mechanism is typically catheter contamination from opening capsules in patient rooms. Many hospitals have formal policies restricting S. boulardii in ICU.
- Healthy adults and immunocompetent patients tolerate extremely well. The safety profile in routine use is among the best of any probiotic in the supplement literature.
- Mild GI upset (gas, bloating) occasionally reported, typically self-limited and resolves with continued use or dose reduction.
- Pediatric safety: extensive trial data in children with no significant adverse signals. The Vandenplas pediatric acute diarrhea protocols have been administered to thousands of children.
- Pregnancy and breastfeeding: limited systematic safety data at supplement doses; existing evidence does not suggest significant risk. OB-GYN guidance reasonable.
- Antibiotic-resistant, the major mechanistic advantage. This is also the regulatory concern that has slowed Asian market entry in some jurisdictions where antibiotic-resistant organisms in food are restricted.
- Does not permanently colonize the gut, transient passage in days to weeks after discontinuation. This is mechanistically why no dysbiosis or withdrawal occurs.
- Heat-stable, does not require refrigeration. Substantially simplifies travel and storage versus bacterial probiotics that require cold chain.
- Catheter precautions: do NOT open capsules near central venous catheters or on hospital surfaces where CVC patients are treated. The opened capsule can aerosolize and contaminate the line.
What people get wrong
Often saidSaccharomyces boulardii is the same as brewer's or baker's yeast.
ActuallyS. boulardii (CNCM I-745) is a distinct tropical yeast species with documented probiotic properties. Standard baker's yeast (S. cerevisiae) does not have the same clinical evidence and should not be used as a substitute. Strain identity matters.
Often saidS. boulardii colonizes the gut permanently.
ActuallyTransient passage in days to weeks. Cannot establish permanent residence. This is mechanistically why discontinuation does not produce dysbiosis, there is nothing to lose.
Often saidProbiotic yeast and probiotic bacteria are interchangeable.
ActuallyFundamentally different organisms with different mechanisms. S. boulardii is antibiotic-resistant (yeast); Lactobacillus is antibiotic-sensitive (bacterium). The two have complementary but distinct clinical evidence bases.
Often saidYou shouldn't take S. boulardii with antibiotics.
ActuallyOpposite of true, concurrent administration is the indicated protocol for AAD prevention. S. boulardii is inherently antibiotic-resistant. Bacterial probiotics (Lactobacillus, Bifidobacterium) should be timed apart from antibiotics; S. boulardii should not.
Often saidGeneric Saccharomyces boulardii is the same as Florastor.
ActuallyStrain identification matters. CNCM I-745 (Florastor) and CBS 5926 (European products) have the documented clinical evidence. Generic "Saccharomyces boulardii" without strain ID may or may not be functionally equivalent.
Often saidS. boulardii is dangerous because it causes infections.
ActuallyFungemia case reports are real but largely confined to severely immunocompromised patients with central venous catheters. Healthy users and most clinical populations tolerate extremely well. The risk applies to specific populations, not general use.
Often saidHeat-killed S. boulardii works the same as live yeast.
ActuallyThe clinical mechanisms (anti-toxin protease production, immunomodulation, competitive adhesion) require live yeast. Heat-killed preparations have limited evidence and are not the form used in clinical trials.
Who profits, and who pushes back
Lynne McFarland
Career-defining work on AAD prevention meta-analyses. Among the most-cited probiotic researchers globally. Independent academic voice; some industry consulting disclosed.
Christina Surawicz
Foundational C. difficile recurrence trial and subsequent clinical research. Mainstream gastroenterology voice on adjunctive probiotic therapy. Independent academic.
Hania Szajewska
Leading European voice on pediatric probiotic evidence. Multiple consensus statements on Saccharomyces boulardii in pediatric diarrheal disease. Some industry consulting disclosed.
Biocodex / Florastor
Sells this. Has a commercial interest in a product sold as this compound, as of July 2026.
Substantial industry sponsorship of clinical research over decades. The dominant commercial interest in the category. Has funded much of the modern Florastor evidence base while maintaining academic publication standards.
Yvan Vandenplas
Foundational pediatric acute diarrhea evidence. Independent academic voice with substantial industry consulting disclosed.
European Society for Pediatric Gastroenterology
Has issued formal recommendations supporting S. boulardii for AAD prevention in children. Independent guideline body; among the few probiotic strain-specific recommendations in mainstream pediatric guidelines.
ICU and hospital infection control
The fungemia case reports beginning in the 1990s have produced sustained concern in ICU and severely immunocompromised contexts. Many hospitals have formal policies restricting S. boulardii in ICU rooms, particularly with central venous catheters. The mechanism (catheter contamination from opened capsules) is preventable but the risk is real. Routine ICU use is not appropriate.
American Gastroenterological Association guidelines
The 2020 AGA practice guideline on probiotics for gastrointestinal disorders provided conditional recommendations for specific strain/indication combinations. S. boulardii received conditional recommendation for prevention of C. difficile infection in adults and children taking antibiotics. The guideline emphasizes that probiotic recommendations are strain-specific, "Saccharomyces boulardii" generically without strain identifier does not have the same evidence as CNCM I-745.
Mainstream microbiology calibration
S. boulardii's mechanism is genuinely interesting, yeast probiotic with anti-toxin and anti-adhesion properties. However, the consumer marketing sometimes extrapolates from documented diarrheal indications to general "gut health" claims that the evidence does not support. The compound has specific, well-evidenced uses; general daily wellness use in healthy adults is not where the evidence is strongest.
Where the research comes from
| Place | Share of published research |
|---|---|
| Europe | 38% |
| United States | 24% |
| Other | 22% |
| Asia | 16% |
Research published from: France.
How we got here
Henri Boulard's 1923 isolation in Indochina is one of the more dramatic origin stories in pharmaceutical development. The French scientist was studying a cholera outbreak in Saigon and observed that locals who chewed the skin of lychee and mangosteen fruit appeared resistant to severe diarrheal illness. He isolated a yeast from the fruit that he named Saccharomyces boulardii, using his own name in the binomial designation, which is unusual in microbiology and reflects the historical period's naming conventions. The yeast was developed commercially in France through the 1920s-1940s; Laboratoires Biocodex was founded in 1953 specifically to commercialize the strain (CNCM I-745, deposited at the Pasteur Institute's Collection Nationale de Cultures de Microorganismes, the source of the CNCM designation). The modern clinical era began in the 1970s-80s with European trials establishing the AAD prevention indication. The McFarland 1995 meta-analysis was foundational for the modern probiotic evidence base, among the first probiotic agents to demonstrate convincing meta-analytic clinical benefit. The Surawicz 2000 C. difficile recurrence trial extended the evidence to the most clinically meaningful diarrheal indication. The 2000s-2010s saw expansion into pediatric acute diarrhea (Vandenplas series), H. pylori adjunct (Szajewska 2010), traveler's diarrhea, and inflammatory bowel disease. Florastor entered the US market in 2003 through Biocodex's US subsidiary. The Hempel 2012 JAMA network meta-analysis confirmed S. boulardii's position among the most-effective probiotics for AAD prevention across 82 trials, establishing pharmaceutical-grade clinical evidence rivaling or exceeding many drug approvals. The fungemia case reports beginning in the 1990s have been a sustained safety concern in ICU and immunocompromised contexts, leading to hospital policies and FDA awareness communications. The product remains widely used globally with strong consumer recognition in pediatric and travel medicine.
- 1923Henri Boulard isolates the yeast in Saigon during cholera outbreak
- 1947Initial pharmaceutical development in France
- 1953Laboratoires Biocodex founded to commercialize the strain
- 1970s-80sEuropean AAD clinical trials establish prevention indication
- 1995McFarland AAD meta-analysis, foundational modern evidence
- 2000Surawicz C. difficile recurrence trial
- 2003Florastor enters US market via Biocodex US
- 2006Updated McFarland AAD meta-analysis (25 RCTs)
- 2009Vandenplas pediatric acute diarrhea consolidation
- 2010Szajewska H. pylori adjunct meta-analysis
- 2012Hempel JAMA network meta-analysis (82 trials)
- 2020sHospital fungemia policies become more formalized in ICU
What we do not know
- Whether high-dose protocols (1g/day or higher) produce proportionally better outcomes for recurrent C. difficile, or whether ceiling effects emerge.
- Whether S. boulardii has a meaningful role in inflammatory bowel disease maintenance, the Plein 2003 Crohn's evidence is promising but underpowered.
- Whether the fungemia risk profile extends beyond established immunocompromise categories, case-control studies in marginally-compromised patients are limited.
- How S. boulardii compares head-to-head with fecal microbiota transplantation for recurrent C. difficile in the modern era.
- Whether next-generation engineered S. boulardii strains (with additional therapeutic capabilities) will reach clinical use, current research is advancing.
- Why generic S. boulardii without CNCM I-745 strain specification has variable clinical performance, strain-level quality control varies by manufacturer.
Legal status
Universally available globally. Marketed as Florastor (US, by Biocodex) and Yomogi/Perenterol (Europe, by Sanofi and licensees). Prescription status varies by country, over-the-counter in the US, prescription in some European countries. Approved in many countries as adjunctive therapy for diarrheal conditions. The pediatric formulation (sachets, lower-dose capsules) is widely used in European and Asian pediatric medicine. Cost is moderate, typically $20-40 per month at standard dose.
Status current as of July 2026. Regulatory positions change, sometimes quickly.
The market for this
What follows describes how this is bought and sold. It is not a buying guide and it is not an endorsement of any seller.
Biocodex (France) manufactures the original CNCM I-745 strain marketed globally as Florastor and similar names. Sanofi licensed the CBS 5926 strain for the European Yomogi/Perenterol products. Both are pharmaceutical-grade with extensive purity and CFU verification. Generic S. boulardii from supplement manufacturers without strain identification represents quality uncertainty, the strain may or may not be functionally equivalent to the clinical-trial reference strains. Premium brands consistently disclose strain identifier on the label. Florastor specifically dominates the US market with extensive pharmacy distribution and consumer recognition.
At a glance
- Organism
- Yeast (Saccharomyces boulardii), not a bacterium
- Reference strain
- CNCM I-745 (Florastor)
- Standard dose
- 250mg twice daily (5B CFU)
- Discovery
- Henri Boulard, 1923, Indochina
- Origin
- Lychee and mangosteen fruit
- Antibiotic resistance
- Inherent, yeasts not affected by antibacterials
What this entry does not yet cover
What follows is unfinished work on our side, not a finding about Saccharomyces boulardii. A short entry is not a safe entry.
- Cost and market. We have not documented what it sells for or who sells it.
- Supply chain. We have not mapped where it is made.
- Who uses it. We have not documented the user groups.
- What could change. No forward-looking summary yet.
- How it compares. We have not set it against the alternatives.
- Children and teenagers. We have not checked what is known about younger people.
- Where we land. We have not taken a position on this yet.
Sources
AAD prevention RR 0.47, NNT ~10; per-indication evidence grading including C. difficile, traveler's, Crohn's, H. pylori, IBS; strong safety profile in trials
EMA/CMDh concluded fungaemia risk outweighs benefit in critically ill/immunocompromised; mandated contraindication and warnings; November 2017 decision
EMA/CMDh scientific conclusions, Saccharomyces boulardii, PSUSA/00009284/201702
Cumulative fungaemia case counts and fatal outcomes; contraindication in patients with central venous catheters; risk factors
NPRA Malaysia safety alert, Saccharomyces boulardii: Risk of fungaemia (summarizing EMA PSUR)
Seven fungemia cases in a single ICU over ~2 years, all ventilated patients on broad-spectrum antibiotics with central lines
Outbreak of fungemia in patients neighboring those treated with the probiotic, implicating airborne/handling contamination near central lines
S. boulardii CNCM I-745 reduces AAD risk in children and adults (~51-57 percent) and shortens pediatric acute diarrhea; well tolerated
Primary CDI prevention pooled OR 0.71 (95% CI 0.46-1.10, not significant); recurrence benefit mainly with high-dose vancomycin
Discovery history: Henri Boulard isolated the yeast in 1923 from lychee and mangosteen peels in Indochina during cholera outbreaks; Biocodex acquired rights 1953, registered CNCM I-745 as a drug 1961
Saccharomyces boulardii, Wikipedia (with Biocodex heritage corroboration)
Biocodex heritage: acquisition of Boulard's strain and development of the registered medicinal product
S. boulardii as adjunct to vancomycin in C. difficile infection: recent randomized controlled trial
The studies that matter
Henri Boulard isolation1923
French scientist Boulard isolated the yeast in Indochina during a cholera outbreak after observing that locals chewing lychee and mangosteen fruit appeared protected. The foundational origin story of the only commercial probiotic yeast.
McFarland AAD meta-analysis1995
Foundational meta-analysis of probiotics for antibiotic-associated diarrhea, with S. boulardii showing the strongest effect of any single agent. Established the AAD indication.
Surawicz C. difficile recurrence trial2000
RCT of S. boulardii + vancomycin/metronidazole for recurrent C. difficile infection: significant reduction in further recurrence versus standard therapy alone. Foundational C. difficile evidence.
McFarland AAD meta-analysis update2006
Pooled analysis of 25 RCTs in adults and children: S. boulardii reduced AAD risk by approximately 50%. Among the strongest probiotic-prevention evidence in the entire literature.
Vandenplas pediatric acute diarrhea2009
Pooled analysis in children with acute infectious gastroenteritis: significant reduction in diarrhea duration (~1 day) versus standard care. Established the acute diarrhea pediatric indication.
Szajewska H. pylori meta-analysis2010
Adjunctive S. boulardii in H. pylori eradication: improved eradication rates and reduced therapy-related side effects when added to standard triple/quadruple therapy.
McFarland traveler's diarrhea review2007
Pooled trial evidence supports modest reduction in traveler's diarrhea incidence with prophylactic S. boulardii during travel to high-risk destinations.
Plein Crohn's disease maintenance2003
Small German trial showing S. boulardii adjunct to maintenance therapy reduced relapse rates in Crohn's disease in remission. Preliminary IBD evidence.
Hempel JAMA AAD network meta-analysis2012
JAMA-published network meta-analysis confirming S. boulardii among the most effective probiotic agents for AAD prevention across 82 trials.