Causes of Blood in Stool Blood in the stool means there is bleeding somewhere in your digestive tract. Bleeding that happens higher up in the digestive tract may make stool appear black and tarry. Possible causes of blood in stool include: Diverticular disease. Anal fissure Colitis . Inflammation of the colon. Peptic ulcers Polyps or cancer Varicose veins of the esophagus or tears in the esophagus can lead to severe blood loss. Long-term use or high doses of anti-inflammatory drugs such as aspirin, ibuprofen, and naproxen can also cause ulcers. A doctor may use one of several techniques to stop acute bleeding. Beyond stopping the immediate bleeding, if necessary, treatment involves addressing the cause of bleeding to keep it from returning. Treatment varies depending on the cause and may include medications such as antibiotics to treat H. pylori, ones to suppress acid in the stomach, or anti-inflammatory drugs to treat colitis. Surgery may be needed to remove polyps or the parts of the colon damaged by cancer, diverticulitis, or inflammatory bowel disease. Depending on the cause, however, treatment may involve simple things you can do on your own. These including eating a high-fiber diet to relieve constipation that can cause and aggravate hemorrhoids and anal fissures, and sitting in warm or hot baths to relieve fissures. Your doctor will prescribe or recommend treatment based on the diagnosis.