Saccharomyces boulardii: new research confirms effectiveness

Saccharomyces boulardii is a very well-researched probiotic, with several hundred peer-reviewed studies to its credit, many from the past two decades. It’s now the first choice for antibiotic-associated diarrhea, C. difficile colitis, and “traveler’s diarrhea.” It can also help in addressing irritable bowel syndrome, ulcerative colitis and Crohn’s disease. Here are some recent research highlights:

–Harvard Medical School researchers located specific pathways by which Saccharomyces boulardii decreases intestinal inflammatory responses; their 2006 report helps explain the broad range of protective effects that the probiotic exerts in a variety of gastrointestinal disorders.

–A 2006 meta-analysis (combined study of multiple individual studies) found that Saccharomyces boulardii was the only probiotic effective against Clostridium difficile disease, a common form of antibiotic-associated diarrhea.

–A 2008 study, meanwhile, found that Crohn’s patients receiving Saccharomyces boulardii treatment showed significant improvements in intestinal function compared with those given a placebo (dummy pill).

–Most recently, an investigation published in 2009 found that, of a variety of probiotics, Saccharomyces boulardii was uniquely able to stimulate production of secretory IgA, the main immunoglobin found in mucus, saliva, and secretions from the intestine and lining of the lungs, and a main component of the body’s protective mechanism against pathogens. (Thus Saccharomyces boulardii may now be credited with a general immune-modulating/strengthening ability.)


Sougioultzis S, Simeonidis S, Bhaskar KR, Chen X, Anton PM, Keates S, Pothoulakis C, Kelly CP. Saccharomyces boulardii produces a soluble anti-inflammatory factor that inhibits NF-kappaB-mediated IL-8 gene expression. Biochem Biophys Res Commun. 2006 Apr 28;343(1):69-76.

McFarland LV. Meta-analysis of probiotics for the prevention of antibiotic associated diarrhea and the treatment of Clostridium difficile disease. Am J Gastroenterol. 2006 Apr;101(4):812-22.

Garcia Vilela E, De Lourdes De Abreu Ferrari M, Oswaldo Da Gama Torres H, Guerra Pinto A, Carolina Carneiro Aguirre A, Paiva Martins F, Marcos Andrade Goulart E, Sales Da Cunha A. Influence of Saccharomyces boulardii on the intestinal permeability of patients with Crohn’s disease in remission. Scand J Gastroenterol. 2008;43(7):842-8.

Flaviano S. Martins, Aparecida A. Silva, Angélica T. Vieira, Flávio H. F. Barbosa, Rosa M. E. Arantes, Mauro M. Teixeira and Jacques Robert Nicoli. Comparative study of Bifidobacterium animalis, Escherichia coli, Lactobacillus casei and Saccharomyces boulardii probiotic properties.
Archives of Microbiology, Volume 191, Number 8 / August, 2009.

Saccharomyces boulardii is available from NYBC as Florastor, recognized as the most reliable commercially available form of the probiotic.

Saccharomyces boulardii lyo: indications and dosage suggestions

NYBC stocks the probiotic Florastor, which is Saccharomyces boulardi lyo (lyo = freeze dried, the best means discovered for preserving the effectiveness of this agent). Saccharomyces boulardii, a yeast first investigated by French microbiologist Henri Boulard in Indochina in the 1920s, has been widely researched and distributed over the last fifty years, though it has a longer history of use in Europe than in the US.

We’re glad that Florastor has become available in the United States in the last five years, since before that we were obliged to import this pharmaceutical grade probiotic from Europe; the US versions of Saccharomyces boulardii often seemed quite a bit less effective, perhaps because the European production techniques were more advanced.

Here are the main indications/conditions for which Saccharomyces boulardii has been investigated:

Acute Diarrhea
A controlled study found a significant reduction in symptoms of diarrhea in adults taking 250mg of S. boulardii twice a day for five days or until symptoms were relieved.

Irritable Bowel Syndrome
A placebo-controlled study found that patients with diarrhea due mainly to irritable bowel syndrome (IBS) had a significant reduction in number and consistency of bowel movements.
Suggested dosage is 250mg twice daily.

Inflammatory Bowel Disease
Additional benefits to inflammatory bowel disease (IBD) patients may be found in 1) prevention of relapse in Crohn’s disease patients currently in remission and 2) benefits to ulcerative colitis patients with moderate symptoms. Suggested dosage is three 250mg capsules a day.

Antibiotic-Associated Diarrhea
Some evidence for its use in the prophylaxis (prevention) of antibiotic-associated diarrhea (AAD) in adults. Suggested dosage: 250mg twice a day with the standard antibiotic course.

HIV/AIDS-Associated Diarrhea
Saccharomyces boulardii was shown to significantly increase the recovery rate of stage IV AIDS patients suffering from diarrhea versus placebo. On average, patients receiving S. boulardii gained weight while the placebo group lost weight over the 18 month study. There were no reported adverse reaction observed in these immunocompromised patients.

Recurrent Clostridium difficile Infection
Two 500mg doses per day of Saccharomyces boulardii when taken with one of two antibiotics (vancomycin or metronidazole) were found to significantly reduce the rate of recurrent Clostridium difficile (pseudomembranous colitis) infection. However, note that significant benefit was not found for prevention of an initial episode of Clostridium difficile-associated disease.

For more on Saccharomyces boulardii, see the NYBC entry:

Note that non-member price is $30, but member price is ONLY $29. (NYBC Membership costs $5, $10, or $25 per year, depending on income.)
Some citations (there are many more, since Saccharomyces boulardii is among the most-studied probiotics):

–Höcher W, Chase D, Hagenhoff G (1990). “Saccharomyces boulardii in acute adult diarrhoea. Efficacy and tolerance of treatment”. Münch Med Wochenschr 132: 188–92. 
–McFarland L, Surawicz C, Greenberg R (1994). “A randomised placebo-controlled trial of Saccharomyces boulardii in combination with standard antibiotics for Clostridium difficile disease”. J Am Med Assoc 271: 1913–8. 
–Maupas J, Champemont P, Delforge M (1983). “Treatment of irritable bowel syndrome with Saccharomyces boulardii: a double blind, placebo controlled study”. Medicine Chirurgie Digestives 12(1): 77–9. 
–Guslandi M, Mezzi G, Sorghi M, Testoni PA (2000). “Saccharomyces boulardii in maintenance treatment of Crohn’s disease”. Dig. Dis. Sci. 45 (7): 1462–4. PMID 10961730. 
–Guslandi M, Giollo P, Testoni PA (2003). “A pilot trial of Saccharomyces boulardii in ulcerative colitis”. Eur J Gastroenterol Hepatol 15 (6): 697–8. doi:10.1097/01.meg.0000059138.68845.06. PMID 12840682. 
–Saint-Marc T, Blehaut H, Musial C, Touraine J (1995). “AIDS related diarrhea: a double-blind trial of Saccharomyces boulardii”. Sem Hôsp Paris 71: 735–41. 

Saccharomyces boulardii: a probiotic now used world-wide for gastrointestinal health

Saccharomyces boulardii is a probiotic that has been commercially distributed for nearly fifty years as an aid to gastrointestinal health, finding a particular application to antibiotic-related diarrhea and the stubborn C. difficile infection.

The manufacturer Biocodex, which has produced this probiotic for many decades, now makes it available in the US under the tradename Florastor.

Florastor product description from NYBC Catalog

Here’s a bit of history on the use of Saccharomyces boulardii from the NYBC newsletter THE SUPPLEMENT:

In the 1920s a French microbiologist named Henri Boulard journeyed through Indochina in search of a heat-resistant yeast that could be used to ferment beverages at temperatures above 70° Fahrenheit. When he happened to observe the local population using a tea brewed from litchi fruit skins to combat diarrhea during a cholera epidemic, he was intrigued, and eventually managed to isolate the yeast responsible for this health benefit.

Since this original microbiological detective work, Saccharomyces boulardii (yes, Henri named the creature after himself!) has been commercialized, first in Europe after World War II, and more recently in the USA as well. It has been studied for many decades as a means to control diarrhea, and has shown very good results for a variety of conditions: Clostridium difficile, Irritable Bowel Syndrome, Crohn’s disease, traveler’s diarrhea, and antibiotic-associated diarrhea.

Your gut is normally home to billions of bugs (intestinal flora), which play a significant role in breaking down food and allowing the digestive tract to absorb nutrients. You could say that Saccharomyces boulardii is a “friendly bug,” an introduced species that allows you to restore and maintain a good working set of intestinal flora in your gut. As it aids digestion, Saccharomyces boulardii can also relieve the bloating and gas that often go with microbial imbalance. Further research has also highlighted this yeast’s ability to repair the mucous membrane lining the intestinal walls and to strengthen immune function in the digestive tract.

NYBC stocks Florastor®, a freeze-dried form of Saccharomyces boulardii that does not need to be refrigerated and has a shelf life of three years. Florastor® is resistant to all commonly-used antibiotics (except anti-fungals), and so it can be taken along with antibiotic treatment to keep intestinal flora in balance. It’s also worth noting that, with a history of use spanning more than 50 years, Saccharomyces boulardii has an excellent safety record for all ages, including children.

One caution, especially important for people with HIV: if you have persistent, serious diarrhea, it’s important that you get an accurate diagnosis of any underlying problem. Simply treating yourself with Saccharomyces boulardii, even if you gain some relief, is not sufficient, since you may be overlookingv a root cause of the condition that needs to be addressed.