When your gut feels off after antibiotics or a bad trip abroad, Saccharomyces boulardii, a non-pathogenic yeast used as a probiotic to support gut health and prevent diarrhea. Also known as Saccharomyces cerevisiae var. boulardii, it’s not a bacteria—it’s a friendly yeast that survives stomach acid and works differently than most probiotics. Unlike lactobacillus or bifidobacterium strains, this yeast doesn’t colonize your gut. Instead, it rides through like a temporary repair crew, calming inflammation, blocking bad bugs, and helping your own good bacteria bounce back.
It’s often used for antibiotic-associated diarrhea, a common side effect of antibiotics that disrupts the natural balance of gut microbes. Studies show it cuts the risk by about 50% in adults and kids. It also helps with traveler’s diarrhea, a gut infection caused by contaminated food or water, often from E. coli or other pathogens. People taking it before or during travel report fewer stomach crashes. And if you’ve had recurring Clostridioides difficile, a dangerous gut infection that causes severe diarrhea and can return after treatment, this yeast is one of the few non-antibiotic tools doctors recommend to prevent relapse.
You’ll find it in capsules, powders, and sometimes in combination with other probiotics. It’s stable at room temperature—no refrigeration needed—which makes it handy for travel or busy households. Most people take it for a week or two, but some use it longer under medical guidance. It’s generally safe, even for kids and older adults, though people with central lines or weakened immune systems should check with their doctor first.
The posts below dig into how this yeast fits into real-world health scenarios—from managing side effects of strong meds to supporting recovery after gut infections. You’ll find practical advice on when to use it, what to expect, and how it compares to other options. Whether you’re dealing with antibiotic mess, a stubborn case of traveler’s tummy, or just trying to reset your gut after a rough patch, these guides give you the no-fluff facts you need.
Learn how to space probiotics and antibiotics correctly to prevent diarrhea and protect your gut microbiome. Discover which strains work best, how long to take them, and the exact timing that makes the difference.
