Overview

Gastrointestinal (GI) bleeding is a sign of a disorder in the digestive tract. The blood often shows up in stool or vomit but isn't always obvious. Stool may look black or tarry. Bleeding can range from mild to severe and can be life-threatening.

Imaging technology or an endoscopic investigation can usually locate the cause of the bleeding. Treatment depends on the where the bleeding is located and how severe it is.

Symptoms

Symptoms of GI bleeding can be easy to see, called overt, or not so obvious, known as occult. Symptoms depend on the rate of bleeding as well as the location of the bleed, which can be anywhere on the GI tract, from where it starts — the mouth — to where it ends — the anus.

Overt bleeding might show up as:

  • Vomiting blood, which might be red or might be dark brown and look like coffee grounds.
  • Black, tarry stool.
  • Rectal bleeding, usually in or with stool.

With occult bleeding, you might have:

  • Lightheadedness.
  • Difficulty breathing.
  • Fainting.
  • Chest pain.
  • Abdominal pain.

Symptoms of shock

If your bleeding starts suddenly and gets worse quickly, you could go into shock. Symptoms of shock include:

  • Weakness or fatigue.
  • Dizziness or fainting.
  • Cool, clammy, pale skin.
  • Nausea or vomiting.
  • Not urinating or urinating a little at a time.
  • A gray or bluish tinge to lips or fingernails.
  • Changes in mental status or behavior, such as anxiousness or agitation.
  • Unconsciousness.
  • Rapid pulse.
  • Rapid breathing.
  • Drop in blood pressure.
  • Enlarged pupils.

When to see a doctor

If you have symptoms of shock, you or someone else should call 911 or your local emergency medical number. If you're vomiting blood, see blood in your stools or have black, tarry stools, seek immediate medical care. If you notice any symptoms of GI bleeding, make an appointment with your doctor.

Causes

Gastrointestinal bleeding can happen either in the upper or lower gastrointestinal tract.

Upper GI bleeding

Causes of upper GI bleeding can include:

  • Peptic ulcer. This is the most common cause of upper GI bleeding. Peptic ulcers are open sores that develop on the inside lining of your stomach and the upper part of your small intestine. Stomach acid, either from bacteria or use of anti-inflammatory medicines, such as ibuprofen or aspirin, damages the lining, causing sores to form.
  • Tears in the lining of the tube that connects your throat to your stomach, called the esophagus. Known as Mallory-Weiss tears, they can cause a lot of bleeding. These are most common in people who drink alcohol to excess, leading to retching and vomiting.
  • Enlarged veins in the esophagus, called esophageal varices. This condition occurs most often in people with serious liver disease, most commonly due to excessive alcohol use.
  • Portal hypertensive gastropathy. This condition occurs most often in people with serious liver disease, most commonly due to excessive alcohol use.
  • Esophagitis. This inflammation of the esophagus is most often caused by gastroesophageal reflux disease (GERD).
  • Abnormal blood vessels. At times abnormal blood vessels, small bleeding arteries and veins may lead to bleeding.
  • Hiatal hernia. Large hiatal hernias may be associated with erosions in the stomach, leading to bleeding.
  • Growths. Though rare, upper GI bleeding can be caused by cancerous or noncancerous growths in the upper digestive tract.

Lower GI bleeding

Causes can include:

  • Diverticular disease. This involves the development of small, bulging pouches in the digestive tract, called diverticulosis. If one or more of the pouches become inflamed or infected, it's called diverticulitis.
  • Inflammatory bowel disease (IBD). This includes ulcerative colitis, which causes swollen tissues and sores in the colon and rectum. Another form of IBD, Crohn's disease, involves swollen, irritated tissues in the lining of the digestive tract.
  • Proctitis. Inflammation of the lining of the rectum can cause rectal bleeding.
  • Tumors. Noncancerous or cancerous tumors of the esophagus, stomach, colon or rectum can weaken the lining of the digestive tract and cause bleeding.
  • Colon polyps. Small clumps of cells that form on the lining of your colon can cause bleeding. Most are harmless, but some might be cancerous or can become cancerous if not removed.
  • Hemorrhoids. These are swollen veins in your anus or lower rectum, such as varicose veins.
  • Anal fissures. An anal fissure is a small tear in the thin, moist tissue that lines the anus.

Complications

A gastrointestinal bleed can cause:

  • Anemia.
  • Shock.
  • Death.

Prevention

To help prevent a GI bleed:

  • Limit your use of nonsteroidal anti-inflammatory drugs.
  • Limit your use of alcohol.
  • If you smoke, quit.
  • If you have GERD, follow your health care team's instructions for treating it.
By Mayo Clinic Staff