Black or tarry stools with a foul smell are a sign of a problem in the upper digestive tract. It most often indicates that there is bleeding in the stomach, small intestine, or right side of the colon.
The term melena is used to describe this finding.
Stools - bloody; Melena; Stools - black or tarry; Upper gastrointestinal bleeding; Melenic stools
Eating black licorice, blueberries, blood sausage or taking iron pills, activated charcoal, or medicines that contain bismuth (such as Pepto-Bismol), can also cause black stools. Beets and foods with red coloring can sometimes make stools appear reddish. In all 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.
The color of the blood in the stools can indicate the source of bleeding.
Peptic ulcers are the most common cause of acute upper GI bleeding. Black and tarry stools may also occur due to:
Contact your health care provider right away if:
In children, a small amount of blood in the stool is most often not serious. The most common cause is constipation. You should still tell your child's provider if you notice this problem.
Your provider will take a medical history and perform a physical exam. The exam will focus on your abdomen.
You may be asked the following questions:
You may need to have one or more tests to look for the cause:
Severe cases of bleeding that cause excessive blood loss and a drop in blood pressure may require surgery or hospitalization.
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Kovacs TO, Jensen DM. Gastrointestinal hemorrhage. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 126.
Meguerdichian DA, Goralnick E. Gastrointestinal bleeding. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 9th ed. Philadelphia, PA: Elsevier; 2018:chap 27.
Savides TJ, Jensen DM. Gastrointestinal bleeding. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 11th ed. Philadelphia, PA: Elsevier; 2021:chap 20.
Reviewed By: Michael M. Phillips, MD, Clinical Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.