Overview

Causes of bleeding in the stomach and intestines (digestive tract) include:

• Regular use of non-steroidal anti-inflammatory drugs (NSAIDs). Examples are aspirin and ibuprofen. These medicines can irritate the stomach lining and cause an ulcer.
• Inflammatory bowel disease.
• Colon polyps or colorectal cancer, especially in older adults. It is important to find and treat these as early as possible. Without treatment, they may be life-threatening.
• Frequently occurring hemorrhoids. People with hemorrhoids often don't seek treatment right away. They can have chronic bleeding as a result.
• Esophagitis. This is irritation or inflammation of the esophagus (the tube that connects the throat to the stomach).
• Hookworm and other parasites. These parasites feed upon blood from the intestinal wall (Figure 1). If they aren't treated, they can cause a lot of blood loss.
• Long-distance running (runner's anemia). People who regularly run long distances often have some type of bleeding in the digestive tract.