Bleeding from the stool is dark red in color. In addition to colonoscopy, there are also abdominal CT, capsule endoscopy, barium enema, blood and stool routine tests, which can be diagnosed together with physical examination and medical history. 1. Abdominal CT: Including CT image reconstruction, the intestinal tract can be observed, but it is affected by the intestinal contents, and to a certain extent it is not as intuitive as colonoscopy. 2. Capsule endoscopy: A capsule-shaped micro-camera can be swallowed after the bowel has been prepared. The capsule endoscopy can take pictures of the lower gastrointestinal tract in the body, which is then expelled together with the stool. 3. Barium enema: Barium enema is an oral examination of the intestines with barium by X-ray, which can indirectly observe the intestinal tract. 4. Blood and Stool Routine: This refers to the use of blood tests and stool examination to assist in the diagnosis of some intestinal or abdominal diseases. 5. Physical examination: abdominal examination can be conducted to determine whether there are gastrointestinal diseases, such as gastrointestinal ulcers and other diseases can appear pressure pain. 6. Medical history: If there is a peptic ulcer, or in the recent gastrointestinal organs surgery, such as polypectomy, tumor removal, etc., can be due to wound ulcer bleeding lead to blood in the stool. When there is bleeding in the stool with dark red color, you should consult a doctor to improve the examination and follow the doctor’s instructions for treatment.