Diarrhea for three or four days is usually diarrhea, mostly considered acute gastroenteritis, dyspepsia, irritable bowel syndrome and other gastrointestinal diseases. 1. Acute gastroenteritis: mostly due to factors such as unclean diet or drinking water leading to pathogen infection of the gastrointestinal tract mucosa caused by the patient’s gastrointestinal mucosa congestion, edema and other inflammatory reactions. Patients mainly manifested as abdominal pain and diarrhea, nausea and vomiting, fever, etc., may lead to diarrhea for three or four days. 2. Dyspepsia: patients are usually accompanied by intestinal dysfunction, affecting the patient’s digestion, absorption and elimination of food, so that patients have diarrhea for three or four days. 3. Irritable bowel syndrome: the patient’s intestinal tract is more sensitive compared to normal people, if the abdomen is cold or eat spicy food, it will lead to abdominal pain and diarrhea and other symptoms, which will also make the patient have diarrhea for three or four days. In addition, certain bad eating habits, such as overeating, eating too fast, too cold, too spicy, etc., will lead to patients with diarrhea for three or four days. When the patient has diarrhea for three or four days, it is recommended to consult a doctor in time to identify the cause of the disease and carry out targeted treatment to avoid delaying the condition.