Diarrhea after taking probiotics for the first time may be caused by the drug itself, personal constitution, dosage and other aspects, and needs to be analyzed specifically. At present, the commonly used probiotics include bifidobacteria, clostridium casei, lactobacilli and other preparations, such drugs are suitable for the treatment of intestinal dysfunction caused by intestinal flora imbalance diarrhea, abdominal pain and other intestinal dysfunctions, prohibited for its allergy, the adverse effects are not clear. 1. The drug itself: when the probiotics taken have quality problems or have passed the expiration date, it may lead to diarrhea after taking. 2. Individual constitution: If the user is allergic to or less tolerant of the selected probiotics, or does not meet the indications for such drugs, it may lead to diarrhea after taking. 3. Dosage: When the medication is not regulated according to the requirements of the drug instructions, such as excessive dosage, continue to take too long, etc., may lead to diarrhea after taking the drug. Diarrhea after taking probiotics for the first time has a variety of possible causes, specific must be analyzed under the guidance of the doctor according to the actual situation of the individual, clear reasons and then make the appropriate adjustment of the medication. Do not make blind judgment, self disposal, in order to avoid improper intervention, resulting in adverse consequences.