Swanson Saccharomyces Boulardii with Prebiotic MOS is specially designed for foreign travelers, but it's great for anyone concerned about gastrointestinal stability. Saccharomycesboulardii is a probiotic yeast that survives stomach acid to nourish the intestines, support the immune system and protect the beneficial bacteria that keep you healthy and comfortable. Our Saccharomyces Boulardii with Prebiotic MOS formula is stable at room temperature, making it easy to take with you. Plus, it can be taken with bacterial probiotics and won't interfere with other supplements, so everyone can take it with confidence.