Saccharomyces boulardii has side effects such as hives, allergic reactions, constipation, thirst, angioedema, etc., the exact occurrence of which varies from person to person. Saccharomyces boulardii is available in both bulk and capsule form. It mainly plays a transient microecological regulatory role, and is suitable for the treatment of diarrhea (children and adults), and diarrhea symptoms caused by intestinal flora imbalance. Possible side effects after taking the drug: occasional allergic reactions, urticaria, constipation, thirst; rare angioedema (symptoms of swelling of the face, tongue, throat, difficulty swallowing, urticaria, dyspnea, etc.), rash; very rare fungal infections; and fever, vomiting, itching, septic shock, anaphylactic shock, maculopapular rash, erythema, erythema, redness, and other adverse reactions of unknown frequency. The drug is contraindicated in patients who are allergic to the product, those who have a central intravenous catheter infusion, immunosuppressed, hospitalized due to critical illness or a compromised immune system, intolerance to fructose and lactose. Specific use of the drug should be carried out under the supervision of a specialist.