Constipation and blood in stool is also a very common phenomenon, constipation and blood in stool at the same time, not caused by a single disease, but many kinds of anorectal diseases induced. So, what should I do if I have constipation and bleeding? What causes can cause constipation and bleeding? Constipation and blood causes 1, hemorrhoids patients suffering from, due to pain in the anus when defecating, because of the fear of defecation often inhibit the stool, gradually produce constipation, and constipation and to a certain extent aggravate the hemorrhoids, when the hemorrhoid nucleus is larger, hemorrhoid mucosa tissue thinning, force defecation when the dry fecal mass easy to rub the hemorrhoid mucosa, causing stool bleeding. 2, intestinal polyps, especially rectal polyps bleeding. Most people, due to small polyps are simply raised nodules in the intestinal mucosa, although the intestinal mucosa has polyps formed, but no conscious symptoms. Large polyps are often small tumors with tips, protruding from the intestinal cavity, can move up and down in the intestine, due to fecal pressure and stimulation, the surface often has ulcers, erosion, and even constipation and bleeding. 3, anal fissure Constipation for a long time will cause anal fissure, and once suffering from anal fissure, constipation bleeding will further aggravate, in the force of defecation, dry feces expansion of the anal canal, can make the anal canal small blood vessels tear and bleeding. 4, rectal ulcer bleeding constipation bleeding for the surface of the stool with blood and accompanied by pain in the anal region. 5, intestinal tumor constipation bleeding including rectal tumor, sigmoid tumor, colon tumor, the main symptom is blood in the stool. The main symptom is blood in the stool. Colon tumors often manifest as constipation alternating with diarrhea, with blood, pus and mucus in the stool; rectal tumors are blood in the stool or pus and blood, or mucus and blood with bloody secretions in the stool.