What causes gastrointestinal (GI) bleeding?
Infections, some medicines, and alcohol can damage tissue in the GI tract and produce bleeding. So can growths or the swollen pockets that sometimes form in the walls of the intestines. Blood vessels that are not formed correctly also can bleed. The most common cause of an upper GI bleed is an ulceration that could occur in the duodenum (just beyond the stomach), or in the stomach lining itself or the esophagus. Esophageal varices, or varicose veins, are usually the result of underlying chronic liver disease like cirrhosis and these can often bleed very briskly. A tear at the junction of the esophagus and stomach sometimes also occurs as a result of repeated vomiting or retching. In addition, tumors or cancers of the esophagus or stomach can also present with bleeding. The most common cause of bleeding from the lower GI tract or colon is diverticulosis. This accounts for over 40 percent of these cases. If diverticular disease is not found, then a patient could have an angiodysplasia wh
