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Saccharomyces boulardii
Saccharomyces boulardii (S. boulardii) is a non-pathogenic yeast microbe with properties that protect it against antibiotics, the body’s internal temperatures, and the acidic environments of the gastrointestinal tract. These properties are not typically observed with bacterial probiotics. (2)(9) S. boulardii was first discovered in lychee and mangosteen fruit and is now cultivated for use in supplements as lyophilized powders, capsules, or liquid beverages. (5)
Not to be confused with: Saccharomyces cerevisiae (7)
Main uses
- Diarrhea
- Gastrointestinal disorders
- Parasitic infections
Formulations
Dosing & administration
| Acute diarrhea | ||
|---|---|---|
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General outcomes from A-level evidence |
No data currently available. |
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Dosing & administration |
500-750 mg w/ concurrent therapy, 8-10 days |
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Outcomes |
↓ diarrhea severity score, Entamoeba histolytica dysentery (7) |
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Class of evidence
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| Antibiotic-associated diarrhea | ||
|---|---|---|
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General outcomes from A-level evidence |
No data currently available. |
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Dosing & administration
|
500-1000 mg w/ concurrent therapy, + 2 weeks |
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Outcomes |
↑ prevention of AAD (7) |
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Class of evidence
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Dosing & administration
|
Children: 250-500 mg w/ concurrent therapy Adults: up to 1000 mg w/ concurrent therapy
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Outcomes |
↓ risk of AAD from 20.9% to 8.8% ↓ risk of AAD from 17.4% to 8.2% (8) |
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Class of evidence
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| Clostridium difficile | ||
|---|---|---|
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General outcomes from A-level evidence |
No data currently available. |
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Dosing & administration
|
1000 mg w/ concurrent therapy, 4 weeks |
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|
Outcomes |
↓ C. difficile recurrence post-eradication (7) |
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Class of evidence |
A |
|
| Giardiasis | ||
|---|---|---|
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General outcomes from A-level evidence |
No data currently available. |
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Dosing & administration
|
500 mg w/ concurrent therapy, 4 weeks
|
|
|
Outcomes |
↓ giardia cyst count (1) |
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|
Class of evidence |
B |
|
| Helicobacter pylori | ||
|---|---|---|
|
General outcomes from A-level evidence |
No data currently available. |
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|
Dosing & administration
|
1000 mg w/ concurrent therapy, 2 weeks
|
|
|
Outcomes |
↓ epigastric distress, global dyspepsia symptom scores, AAD (7) |
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|
Class of evidence |
A |
|
| HIV-related diarrhea | ||
|---|---|---|
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General outcomes from A-level evidence |
No data currently available. |
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Dosing & administration
|
3000 mg, 7 days
|
|
|
Outcomes |
↓ diarrhea frequency (7) |
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|
Class of evidence |
A |
|
| Inflammatory bowel disease | ||
|---|---|---|
|
General outcomes from A-level evidence |
No data currently available. |
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|
Dosing & administration
|
750-1000 mg w/ concurrent therapy, 7 weeks-6 months
|
|
|
Outcomes |
↓ ulcerative colitis, Crohn’s bowel movements, relapse in Crohn’s treatment (7) |
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Class of evidence
|
|
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|
Dosing & administration
|
100 mg w/ concurrent therapy, 3 months
|
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|
Outcomes |
↓ intestinal permeability in Crohn’s (3) |
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Class of evidence
|
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|
| Irritable bowel syndrome | ||
|---|---|---|
|
General outcomes from A-level evidence |
May improve hyperandrogenemia, ovarian histomorphology, folliculogenesis, and luteinisation processes, as well as insulin resistance and chronic inflammation (58) |
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Dosing & administration
|
500 mg, 4 weeks
|
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Outcomes |
↓ bowel movements, global IBS symptoms (7) |
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Class of evidence
|
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|
| Nutrient-associated diarrhea | ||
|---|---|---|
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General outcomes from A-level evidence |
No data currently available. |
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Dosing & administration
|
2000 mg, 8-28 days
|
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Outcomes |
↓ occurrence of diarrhea and number of days (7) |
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Class of evidence
|
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Adverse effects
S. boulardii is generally regarded as safe, however, an increased risk of non-infectious adverse effects (e.g., biliary tract stenoses, fistulas, lienalis-steal syndrome, abdominal hemorrhage, and acute renal failure) has been found in specific groups (e.g., immunocompromised patients, transplant patients or patients with pancreatitis). Rare cases of fungemia associated with S. boulardii have also been reported. (6)(7)(10)
Pharmacokinetics
Absorption
Distribution
- Survives in the intestinal tract to reach the colon, its most common target. (6)
Metabolism
- S. boulardii is not metabolized but rather dies within the competitive environment of the gastrointestinal tract and is excreted. Levels found excreted in the stool can be 100-1000 times smaller than the ingested dose. (6)