GI bleeding can be categorized into upper and lower sources. Upper GI bleeding typically originates from the esophagus, stomach, or duodenum and may be caused by conditions such as peptic ulcers, esophageal varices, and gastritis. Lower GI bleeding usually originates from the small intestine, colon, or rectum and may be caused by diverticulosis, colorectal cancer, and inflammatory bowel disease.
