Normal people will not have diarrhea after the MMR vaccine, and the symptoms of diarrhea are considered to be caused by poor diet or diseases, such as indigestion and enteritis. MMR vaccine can be used to prevent measles, mumps, rubella three infectious diseases, the vaccine’s adverse reactions do not include diarrhea, the common cheek, cervical lymph node swelling, or mild fever. If diarrhea occurs after MMR vaccination, if the degree is mild, it is considered to be caused by unclean diet, intake of spoiled food or poor dietary habits and overeating. If the degree of diarrhea is more serious, accompanied by other symptoms, such as abdominal pain, nausea, etc., is considered to be dyspepsia, enteritis and other diseases caused by the need for timely consultation to identify the cause of the disease, further targeted treatment. After the MMR vaccine generally do not have diarrhea, if the diarrhea symptoms are more serious, you can consult a doctor for relevant examinations to determine the cause of the disease.