Sudden abdominal pain and diarrhea may be due to physiological reasons caused by improper diet or pathological reasons such as gastrointestinal diseases. 1. Physiological causes: improper diet, overeating, eating spicy and stimulating food, or greasy and indigestible food, as well as expired, spoiled and unclean food, as well as drinking alcohol and carbonated beverages, may cause gastrointestinal dysfunction, resulting in abdominal pain and diarrhea, etc. In this case, the patient should eat a light diet, regular diet and quit smoking and drinking. 2. Pathological causes: acute gastroenteritis, patients with acute gastroenteritis, gastrointestinal malignant tumors and pseudomembranous enteritis, patients will have sudden abdominal pain and diarrhea, according to the symptoms of anti-infection, rehydration, or the application of drug therapy. Sudden abdominal pain and diarrhea may also be caused by other reasons, it is recommended to consult a doctor in a timely manner, under the guidance of a doctor to clarify the cause and targeted treatment, do not take medication, so as not to delay the condition.