What causes Stools to become black?

Some individuals go to the bathroom and notice their stools are black. Often they may also smell terrible. While some stools can be dark, others can be maroon or very red. When stools have a dark color, this is often an indication of the presence of blood. The blood may have come from anywhere from the digestive tract. Dark stools often result because of combination with blood and acid. This commonly happens when someone has an ulcer in the stomach which is bleeding slowly. The blood has enough time to mix with the stools and turns them black. When blood is present in black colored stools it is often referred to as melena.

Blood in the stools can come from anywhere in the digestive tract. Small amounts of blood which are not visible with the naked eye can only be detected with a fecal occult blood test. If the fecal occult test confirms the presence of blood in stools, then the source of bleeding must be identified. The most common causes of black stools are due to bleeding from the esophagus or a stomach ulcer.

When stools have bright blood on them, the source of blood is usually in the colon or rectum. Causes of bright red blood include hemorrhoids, diverticulitis, inflammatory bowel disease and cancers.

Non medical causes of dark stools include ingestion of black licorice, iron pills, pepto bismol or blueberries. There are a variety of foods that can mimic blood in the stools. These include broccoli, cabbage, cauliflower, cucumber, vitamin C, potatoes and horse radish.

Drugs which one must be avoided prior to testing include aspirin and any blood thinners like warfarin or coumadin.

In any case, once blood has been identified in the stools, it is imperative that the health care worker determine the source. In general, the causes of black stool usually reside higher up in the esophagus and stomach. Thus, one may undergo an endoscopy (flexible scope with a camera) or some type of a radiological test (barium swallow). If it is suspected that you may have a bleeding problem in the colon, then a barium enema or a colonoscopy may be the next step.

For those of you who have dark stools and are concerned about the presence of blood, the occult fecal blood test kits are readily available and easy to use. The fecal blood test is relatively inexpensive and the kits costs anywhere form $10-$25. Some insurance carriers and Medicare do cover the costs of fecal blood testing.

For more information on kits to check for blood in the stools, please visit www.medexsupply.com