Saccharomyces sp. boulardii

RANK: Species

TAXONOMY: Saccharomyces sp. boulardii


Saccharomyces boulardii is a tropical strain of yeast first isolated from lychee and mangosteen fruit in 1923 by French scientist Henri Boulard. It is related to, but distinct from, Saccharomyces cerevisiae in several taxonomic, metabolic, and genetic properties.[1] S. boulardii is sometimes used as a probiotic with the purpose of introducing beneficial active cultures into the large and small intestine, as well as conferring protection against pathogenic microorganisms in the host. However, in immunocompromised individuals, S. boulardii has been associated with fungemia or localized infection, which may be fatal. Two studies each showed a significant reduction in the symptoms of acute gastroenteritis in children, versus placebo, by measuring frequency of bowel movements and other criteria. Children over three months are recommended to take two doses of 250 mg a day for five days to treat acute diarrhea. Children under three months are recommended to take half a 250-mg capsule or sachet twice daily for five days.A prospective placebo-controlled study found a significant reduction in symptoms of diarrhea in adults taking 250 mg of S. boulardii twice a day for five days or until symptoms are relieved. A prospective placebo-controlled study found patients with diarrhea-predominant irritable bowel syndrome had a significant reduction on the number and consistency of bowel movements. The addition of S. Boulardii to the standard triple medication protocol for elimination of H. pylori infection showed a significant increase in eradication rates in a meta-analysis though eradication rates were still not exceptional. The supplement also significantly decreased usual side effects of H. pylori eradication therapy including diarrhea and nausea.


Saccharomyces sp. boulardii inhibits growth of
  • Clostridioides difficile
  • Helicobacter pylori

    Metabolic Endproducts
  • Norepinephrine