Stools - bloody; Hematochezia; Melena; Stools - black or tarry
Eating black licorice, lead, iron pills, bismuth medicines like Pepto-Bismol, or blueberries can also cause black stools. Beets and tomatoes can sometimes make stools appear reddish. In these cases, your doctor can test the stool with a chemical to rule out the presence of blood.
Bleeding in the esophagus or stomach (such as with peptic ulcer disease) can also cause you to vomit blood.
Bleeding that takes place in the esophagus, stomach, or the first part of the small intestine most often causes the stool to appear black or tarry. Your doctor may use the term "melena."
Bleeding in the upper part of the GI tract will usually cause black stools due to:
Maroon-colored stolls or bright red blood often men that the blood is coming from the small or large bowel, rectum, or anus. The term "hematochezia" is used to describe this finding.
Abnormal blood vessels
When blood supply is cut off to part of the intestines, called Bowel inschemia
Call your doctor right away if you notice blood or changes in the color of your stool. You should be examined by your doctor even if you think that hemorrhoids are causing the blood in your stool.
In children, a small amount of blood in the stool is usually not serious. The most common cause is constipation. You should still tell your child's doctor if you notice this problem.
Your doctor will take a medical history and perform a physical exam that focuses on your abdomen and rectum.
You may be asked the following questions:
You may need to have one or more tests to look for the cause:
Jensen DM. Gastrointestinal hemorrhage and occult gastrointestinal bleeding. In: Goldman L, Schfer AI, eds Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2001:chap137
Laine L, Jensen DM, American College of Gastroenterology guideline for management of patiant with ulcer bleeding. Am J Gastroenterol. 2012; 107;345-360
Lanza FL, Chan FK, Quigley EM; Practice Parameters Committee of the American College of Gastroenterology. Guidelines for prevention of NSAID-related ulcer complications. Am J Gastroenterol. 2009; 104;728-738
Lieberman DA. Clinical practice. Screening for colorectal cancer. N Engl J Med. 2009;361:1179-1187.