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 anywhere along the GI tract and is typically divided divided into upper and lower GI bleeding. Upper GI bleeding, which is more common, affects the mouth, esophagus, stomach or top part of the small intestine (duodenum). Lower GI bleeding affects the small intestine below the duodenum or the large intestine.

Symptoms of GI bleeding include vomiting blood, passing black or tarry stools or passing red- or maroon-colored stools.

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 and anemia. Acute GI bleeding can lead to shock and even death.

Common causes of GI bleeding include:

• Peptic ulcers
• Inflammation such as esophagitis or gastritis
• Liver disease
• Hemorrhoids
• Diverticular disease
• Side effect of medication
• Celiac disease (gluten intolerance)
• 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.

Many causes of GI bleeding cannot always be prevented. However, in some cases a patient may be able to reduce the risk of bleeding in some cases with lifestyle changes, such as drinking plenty of fluids, eating a high-fiber diet and exercising regularly.