Recommendations on Saccharomyces boulardii and Traveler’s Diarrhea

Evidence Regarding Saccharomyces boulardii for Traveler’s Diarrhea

The 2017 Journal of Travel Medicine expert consensus states that there is insufficient evidence to recommend commercially available probiotics, including Saccharomyces boulardii, for the prevention or treatment of traveler’s diarrhea (consensus, not graded) 1.
The same guidelines highlight major heterogeneity among studies—different probiotic strains, inconsistent dosing, heterogeneous traveler populations, short follow‑up periods, and lack of person‑time analyses—limiting the ability to draw firm conclusions 1.
Two meta‑analyses identified a marginal benefit of probiotics in preventing traveler’s diarrhea, but the evidence was deemed inadequate to support universal recommendations 1.
No randomized controlled trial specifically evaluating S. boulardii in travelers has demonstrated consistent efficacy 1.
The 2001 Alimentary Pharmacology & Therapeutics guideline notes that current probiotic doses provide little or no benefit for acute adult diarrhea, especially within the first 24–48 hours 4.

Antibiotics are not recommended for mild traveler’s diarrhea (strong recommendation, moderate‑quality evidence) 5.
Loperamide or bismuth subsalicylate may be used for symptom control (strong recommendation, moderate‑quality evidence) 5.

Azithromycin (500 mg daily for 3 days or a single 1 g dose) is the preferred antibiotic (strong recommendation, high‑quality evidence) 5.
Loperamide can be employed as adjunct therapy or as monotherapy (strong recommendation, high‑quality evidence) 5.

Azithromycin remains the agent of choice (single 1 g dose or 500 mg daily for 3 days) (strong recommendation, moderate‑quality evidence) 5.

S. boulardii is contraindicated in immunocompromised individuals because of the risk of fungemia or bacteremia (conditional recommendation) 3.

The American Gastroenterological Association conditionally recommends S. boulardii (1 g or 3 × 10¹⁰ CFU per day) to prevent antibiotic‑associated diarrhea, especially with clindamycin, showing an approximate 59 % reduction in Clostridioides difficile‑related diarrhea (conditional recommendation) 3.