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Saccharomyces boulardii is a non-pathogenic tropical yeast first isolated from lychee fruit in 1923. Unlike bacterial probiotics, it is resistant to antibiotics and stomach acid, surviving transit to reach the colon intact. Meta-analyses of dozens of randomized controlled trials consistently support S. boulardii for preventing antibiotic-associated diarrhea (reduces risk by ~50%), traveler's diarrhea, and recurrent C. difficile infection. It also shows benefit in IBS, H. pylori protocols, and pediatric acute gastroenteritis. Standard dose is 5-10 billion CFU per day, especially during and 2 weeks after antibiotic courses.
A beneficial yeast probiotic. The best-evidenced supplement for preventing antibiotic-associated diarrhea.
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