Blood under the intestinal wind is a bowel movement with bloody stools. There are many reasons for bloody stools, such as eating animal offal, pig and lamb blood, and iron-rich vegetables, which can cause black stools. There are also changes in the color of the stool caused by drug metabolism, which can be tested by checking the stool routine plus occult blood. There are also bleeding caused by hemorrhoids, need to improve the spicy, stimulating diet, avoid smoking, avoid alcohol, to have a light diet, but also have a good lifestyle, you can go to the anorectal department to perform anoscopy for a clear diagnosis. Also consider gastrointestinal bleeding, patients need to go to the gastroenterology department of the hospital in time to consider various lesions such as inflammation, ulcer, vascular bleeding, polyp bleeding, tumor, etc. of the digestive system and improve gastroscopy. If it is a general inflammation, oral medication to protect the gastrointestinal mucosa can be taken. If the ulcer is causing bleeding, intravenous fluids such as acid suppressants can be administered to promote healing of the ulcer. In case of severe acute bleeding, emergency treatment with gastrointestinal endoscopy can be performed, applying hemostatic drugs, titanium clips, vascular embolization, etc.