Gastrointestinal Bleeding (GI Bleeding)

Facts You Should Know About Gastrointestinal (GI) Bleeding

Picture of gastrointestinal bleeding in the lower digestive tract.
Picture of gastrointestinal bleeding in the digestive tract.
  • Gastrointestinal (GI) bleeding is when bleeding occurs in any part of the gastrointestinal tract. The GI tract includes your esophagus, stomach, small intestine, large intestine (colon), rectum, and anus. GI bleeding itself is not a disease, but a symptom of any number of conditions.
  • The causes and risk factors for gastrointestinal (GI) bleeding are classified into upper or lower, depending on their location in the GI tract.
  • Causes of upper GI bleeding include
    • peptic ulcers,
    • gastritis (bleeding in the stomach),
    • esophageal varices,
    • cancers, and
    • inflammation of the GI lining from ingested materials.
  • The most common causes and risk factors for lower GI bleeding include
  • Symptoms of GI bleeding often first appear as blood in the vomit or stool, or black, tarry stools. The person also may experience abdominal pain. Symptoms associated with the blood loss include
    • fatigue,
    • weakness,
    • pale skin, and
    • shortness of breath.
  • GI bleeding can usually be diagnosed by a digital rectal exam, an endoscopy or colonoscopy, and lab tests.
  • Treatment for GI bleeding usually includes hospitalization because blood pressure may drop and heart rate may increase and this needs to be stabilized. In some cases, IV fluids or blood transfusions are needed, and surgery may be required.
  • The prognosis for a person with GI bleeding depends upon the cause and location of the bleeding, how bad the bleed is when the person sees the doctor, and any underlying medical conditions that may affect the patient's recovery.

What Are the Signs and Symptoms of Acute and Chronic Gastrointestinal Bleeding?

Acute Gastrointestinal Bleeding

The early signs and symptoms of acute gastrointestinal bleeding are:

  1. It will first will appear as vomiting of red blood
  2. Blood in the stools
  3. Black, tarry stools
  4. Vomiting blood that look like "coffee grounds"

 Symptoms associated with blood loss can include

  1. Fatigue or feeling tired
  2. Weakness
  3. Shortness of breath
  4. Abdominal pain and cramps
  5. Pale appearance
  6. A drop in blood pressure (low blood pressure)
  7. A rapid pulse
  8. Little or no urination
  9. Unconsciousness

Chronic Gastrointestinal Bleeding

Signs and symptoms of chronic (long-term) GI bleeding may go unnoticed or may cause:

  1. Fatigue
  2. Shortness of breath
  3. Anemia
  4. Black stools
  5. A positive test for microscopic blood
  6. Occult bleeding, which may be a symptom of inflammation or a disease, for example, colon (colorectal) cancer.
  7. Blood loss as described above.

What Causes Gastrointestinal Bleeding?

The causes of gastrointestinal (GI) bleeding are classified into upper or lower, depending on their location in the GI tract. Because GI bleeding is a symptom of many conditions, these conditions are all risk factors for getting a GI bleed. Examples of causes of upper and lower gastrointestinal bleeding are:

What Are Causes and Risk Factors for Upper Gastrointestinal Bleeding?

  • Peptic ulcer disease: Peptic ulcers are localized erosions of the mucosal lining of the digestive tract. Ulcers usually occur in the stomach or duodenum. Breakdown of the mucosal lining results in damage to blood vessels, causing abdominal  bleeding.
  • Gastritis: General inflammation of the stomach lining, which can result in bleeding in the stomach. Gastritis also results from an inability of the gastric lining to protect itself from the acid it produces. Causes of gastritis include
  • Esophageal varices: Swelling of the veins of the esophagus or stomach usually resulting from liver disease. Varices most commonly occur in alcoholic liver cirrhosis. When varices bleed, the bleeding can be massive, catastrophic and occur without warning.
  • Mallory-Weiss tear: A tear in the esophageal or stomach lining, often as a result of severe vomiting or retching. Mucosal tears also can occur after seizures, forceful coughing or laughing, lifting, straining, or childbirth. Physicians often find tears in people who have recently binged on alcohol.
  • Cancer: One of the earliest signs of esophageal or stomach cancers may be blood in the vomit or stool.
  • Inflammation: When the mucous membranes break down, they are unable to counteract the harsh effects of stomach acid. NSAIDs, aspirin, alcohol, and cigarette smoking promote gastric ulcer formation. Helicobacter pylori is a type of bacteria that also promotes formation of ulcers.

What Are Causes and Risk Factors for Lower Gastrointestinal Bleeding?

  • Diverticulosis: One of the most common causes of lower GI bleeding. Small out-pockets, or diverticula, form in the wall of the colon (large intestine), usually in a weakened area of the bowel wall. The person may develop several pockets, which are more common in people who have constipation and strain during a bowel movement.
  • Cancers: One of the early signs of colon or rectal cancers may be blood in the stool.
  • Inflammatory bowel disease (IBD): Flares of inflammation from IBD (Crohn's disease and ulcerative colitis) often cause mucousy stool that has blood mixed in it.
  • Infectious diarrhea: Some viruses or bacteria can cause damage to the inner lining of the intestines, which can lead to bleeding.
  • Angiodysplasia: Along with diverticulosis, this is one of the most common causes of lower GI bleeding. Angiodysplasia is a malformation of the blood vessels in the wall of the GI tract. These are most commonly in the large intestine and often bleed. The elderly and people with chronic kidney failure develop the disease most often.
  • Polyps: Intestinal polyps are noncancerous tumors of the GI tract, occurring mostly in people older than 40 years of age. A small proportion of these polyps may transform into cancer. Colon polyps may bleed rapidly, or they may bleed slowly and go undetected.
  • Hemorrhoids and fissures: Hemorrhoids are swollen veins in and around the anus. Repeated stretching from straining during bowel movements causes them to bleed. Bleeding from hemorrhoids is usually mild, intermittent, and bright red. Anal fissures, or tears in the anal wall, also may trigger small amounts of bright red bleeding from the anus. Forceful straining during passage of hard stool usually causes such tears, which can be very painful and may require surgery.

What Procedures and Tests Diagnose the Cause Upper and Lower Gastrointestinal Bleeding?

  • A doctor will perform a complete history and physical exam to evaluate the patient's problem. The doctor may include a digital rectal exam, to test for visible or microscopic blood from the rectum.
  • Lab tests such as complete blood count (CBC), serum chemistries, liver tests, and coagulation studies also can be helpful to determine the rate or severity of bleeding and to determine factors that may contribute to the problem.
  • The doctor may need to perform a procedure called an endoscopy or a colonoscopy. An endoscope is a long tube with a tiny camera at the end. It is passed into the stomach, and the first part of the small intestine. A colonoscopy refers to the passage of a tube with a tiny camera through the rectum into the colon, to directly see the source of bleeding. Both procedures can be diagnostic, finding the source of bleeding; and therapeutic, stopping it.

What Are Treatments for Gastrointestinal Bleeding?

  • There is no home care for heavy gastrointestinal bleeding.
  • Hemorrhoids or anal fissures may be treated with a diet high in fiber, fluids to keep stools soft may be helpful, and stool softeners if necessary. If they do not heal, they may need to have surgery to remove or fix them.
  • Serious gastrointestinal bleeding can destabilize the vital signs of a patient. The patient's blood pressure may fall sharply, and his or her heart rate may increase.
  • The doctor may need to resuscitate the patient with IV fluids and possibly a blood transfusion.
  • In some cases, the patient may need surgery.
  • For an upper GI bleed, such as bleeding from the stomach, patients may be given IV proton pump inhibitors (PPIs) such as omeprazole (Prilosec) to suppress acid.
  • If a large amount of blood is in the upper GI tract, patients may be given prokinetics (medications that help stomach emptying) such as erythromycin or metoclopramide (Reglan) to help clear the stomach of blood, clots, or food residue before an endoscopy procedure to clear the stomach.
  • Other medications may include somatostatin or octreotide (Sandostatin) if there is treatment of variceal (small blood vessel) bleeding, or antibiotics in patients with cirrhosis of the liver.

A person should go to a hospital's emergency department if they have heavy gastrointestinal bleeding.

When Should You Call a Doctor for Gastrointestinal Bleeding?

Any presence of blood in the stool or from the upper gastrointestinal tract is significant and needs medical attention. Black or dark stools may represent slow bleeding into the GI tract and should be treated by a doctor.

Any significant bleeding into the GI tract, either vomited blood or blood through the rectum, should be evaluated in the emergency department.

Which specialties of doctors treat gastrointestinal (GI) bleeding?

You may initially be diagnosed with gastrointestinal (GI) bleeding by your primary care provider (PCP), such as a family practitioner, an internist, or child’s pediatrician. You may also see an emergency medicine specialist in a hospital’s emergency department.

You will likely be referred to a gastroenterologist, a specialist in the digestive tract, for further treatment.

What Are the Complications and Prognosis for Gastrointestinal Bleeding?

The outcome of treatment for gastrointestinal bleeding greatly depends on several factors including:

  • The cause and location of the bleeding
  • The rate of bleeding when the person sees a doctor
  • Prior health problems and conditions
  • Maintain a proper diet and take the medications prescribed as directed.

Follow-up with your doctor on a regular basis to monitor progress, so that the doctor can prevent further progression and complications of gastrointestinal bleeding. 

Sometimes, the complications of gastrointestinal bleeding can be fatal.

How Can You Prevent Gastrointestinal Bleeding?

People can prevent some causes of gastrointestinal bleeding.

  • Avoid foods and triggers, such as alcohol and smoking that increase gastric secretions.
  • Eat a high-fiber diet to increase the bulk of the stool, which helps prevent diverticulosis and hemorrhoids.

What Causes Stool Color Changes?

Stool color changes can occur for a variety of reasons, such as, suggests an underlying medical condition; substances that are added to stool; changes to substances normally present in stool; taking, eating, or drinking of certain liquids, foods, or medications.

Examples of colors of stools and the causes include:

  1. Black, tarry, sticky stools: Gastritis (bleeding from the stomach)
  2. Black stools (no odor, not sticky): Medications like iron pills or bismuth-containing medications (Pepto-Bismol)
  3. Yellow stools: Celiac disease, pancreatic cancer
Saltzman, J.R. "Approach to acute upper gastrointestinal bleeding in adults." UpToDate. May 18, 2021. <>.

Strate, L. "Approach to acute lower gastrointestinal bleeding in adults." UpToDate. June 21, 2021. <>.

United States. NIH. "Acute and Chronic Bleeding Symptoms." July 2016. <>.