Bleeding in the digestive tract is a symptom of a problem rather than a disease itself. Most causes of bleeding are related to conditions that can be cured or controlled, such as hemorrhoids.
The cause of bleeding may not be serious, but locating the source of bleeding is critical. The digestive or gastrointestinal (GI) tract includes the esophagus, stomach, small intestine, colon, rectum, and anus. Bleeding can come from one or more of these areas -- from a small area such as an ulcer on the lining of the stomach or from a more diffuse problem such as inflammation of the colon.
Bleeding can sometimes occur without you even knowing about it. This type of bleeding is called occult or hidden. Fortunately, simple tests can detect occult blood in the stool.
What Causes Bleeding in the Digestive Tract?
Bleeding from the esophagus can be caused by:
Esophagitis and gastroesophageal reflux. Stomach acid that refluxes (returns) back into the esophagus from the stomach can cause an irritation and inflammation of the esophagus (esophagitis) that may lead to bleeding.
Varices. Abnormally enlarged veins usually located at the lower end of the esophagus or the upper stomach, called varices, may rupture and bleed massively. Cirrhosis of the liver is the most common cause of esophageal varices.
Mallory-Weiss tear. This is a tear in the lining of the esophagus that usually is caused by prolonged vomiting but may also result from other causes of increased abdominal pressure, such as coughing, hiccupping, or childbirth.
Bleeding from the stomach can be caused by:
Gastritis. Alcohol, medications including NSAIDs (nonsteroidal anti-inflammatory drugs), aspirin, ibuprofen (Advil, Motrin), or naproxen (Aleve, Naprosyn) and many others can cause stomach ulcers or inflammation (gastritis).
Stomach ulcers and intestinal ulcers. Ulcers in the stomach may enlarge and erode through a blood vessel, causing bleeding. Aside from medication, the most common cause of a stomach ulcer is an infection with a bacterium called Helicobacter pylori. Also, patients suffering from burns, shock, head injuries, or cancer, as well as those who have undergone extensive surgery, may develop stress-related stomach ulcers. Intestinal ulcers are usually caused by excess stomach acid and infection with Helicobacter pylori.
Bleeding from the lower digestive tract (colon, rectum, and anus) can be caused by:
Hemorrhoids. These are probably the most common cause of visible blood in the lower digestive tract, especially blood that appears bright red. Hemorrhoids are enlarged veins in the anal area that can rupture and produce bright red blood, which can show up in the toilet or on toilet paper.
Anal fissures. Tears in the lining of the anus can also cause bleeding. These are often very painful.
Colon polyps. These are growths that can occur in the colon. They can be the precursor of cancer and may cause bleeding.
Intestinal infections. Inflammation and bloody diarrhea can result from intestinal infections.
Ulcerative colitis. Inflammation and extensive surface bleeding from tiny ulcerations can be the reason for blood showing up in the stool.
Crohn's disease. This chronic condition also causes inflammation and can result in rectal bleeding.
Blood vessel abnormalities. As one gets older, abnormalities may develop in the blood vessels of the large intestine, which may result in recurrent bleeding.
Ischemic colitis. Bloody diarrhea, often associated with abdominal pain, can be due to reduced blood flow to the intestine, which results in ischemia, or insufficient oxygen, and damage to cells lining the intestine.