Gastrointestinal bleeding is any type of blood loss that originates in the gastrointestinal (GI) tract, from the mouth to the anus. It can range from nearly undetectable – called occult bleeding – to acute and potentially life-threatening blood loss.

Bleeding can originate in any organ along the GI tract, but is typically divided into upper GI bleeding and lower GI bleeding. Upper GI bleeding, which is more common, affects the mouth, esophagus, stomach and the top portion of the small intestine (duodenum). Lower GI bleeding affects the small intestine below the duodenum and the large intestine, including the colon, rectum and anus.

Symptoms of GI bleeding include vomiting blood (hematemesis), passing black or tarry stools (melena) or passing red- or maroon-colored stools (hematochezia).

Other symptoms include abdominal pain and fatigue. In some cases, such as occult bleeding, patients may not notice any signs of blood loss.

It is recommended that patients immediately contact their physician if they vomit blood or pass blood in their stool. Chronic occult bleeding can lead to iron loss, which can result in anemia. Acute GI bleeding can lead to hypovolemia (a decrease in the volume of circulating blood), shock and even death.

Common causes of GI bleeding include:

• Peptic ulcers
• Internal inflammation (e.g., esophagitis, gastritis, duodenitis)
• Esophageal varices
• Mallory-Weiss tear
• Hemorrhoids
• Diverticular disease
• Cancer of the digestive system

The diagnosis of GI bleeding typically involves an evaluation of the patient’s medical history, a physical examination and a series of diagnostic tests (e.g., fecal tests, endoscopy, colonoscopy).

Treatment will depend on the underlying cause, and can often be performed at the same time as an endoscopy or colonoscopy. Surgery, such as a laparotomy, may be necessary if bleeding does not cease after initial procedures.