Saccharomyces, a genus of yeasts, is widespread in nature and plays a significant role in the food and beverage industry, especially through Saccharomyces cerevisiae, which is used in bread, beer, and wine. However, Saccharomyces boulardii (S. boulardii) has gained particular importance as a probiotic due to its unique properties and health benefits, distinguishing it from other probiotic bacteria.

Saccharomyces boulardii is especially known for its resistance to antibiotics, making it particularly useful in the treatment of antibiotic-associated diarrheal diseases. This yeast can inhibit the growth of harmful microorganisms in the gut, strengthen the intestinal barrier, and modulate the immune system. Because of these properties, it is often used to prevent and treat various types of diarrhea, including traveler's diarrhea and infections with Clostridioides difficile.

Furthermore, Saccharomyces boulardii is being researched in the therapy of chronic inflammatory bowel diseases such as ulcerative colitis and Crohn's disease. Its mechanisms of action are diverse and include interference with pathogenic bacteria, strengthening of the intestinal barrier function, and influencing the immune system.

Saccharomyces boulardii as a probiotic yeast represents an exception in a field that is mainly dominated by bacterial probiotics. Its ability to survive under conditions unfavorable for many bacteria, along with its specific mechanisms of action, make it a valuable tool in probiotic therapy. However, it is important to seek expert advice on its suitability and safety for individual cases.