If the patient has blood in the stool, the first thing to do is to find out whether the patient’s blood pressure and heart rate are stable or not. If the blood pressure goes down and the heart rate goes up, it is likely that the patient will go into shock. Common diseases include ulcerative colitis, colon cancer, tuberculosis of the colon and hemorrhoids, which require e-colonoscopy or finger-anal examination for clarification. If the first three diseases need to stop bleeding, in the case of ulcerative colitis, prednisone should be used to control acute attacks; colon cancer needs to be treated with surgery or chemotherapy or radiotherapy as soon as possible; tuberculosis of the colon needs anti-tuberculosis treatment; hemorrhoids can be treated with saline plus norepinephrine enema to stop bleeding.