causes a large amount of blood to appear in your stool. Bleeding starts
suddenly and usually stops on its own. Abdominal (belly) pain usually does not occur
with the bleeding.
If you have a large amount of blood in your
stool, see a doctor right away. It is possible, but not common, to quickly lose
so much blood that you become lightheaded or weak.
What causes diverticular bleeding?
The reason pouches
(diverticula) form in the colon wall is not completely understood. Doctors
think diverticula form when high pressure inside the colon pushes against weak
spots in the colon wall.
Normally, a diet with enough fiber
(also called roughage) produces stool that is bulky and can move easily through
the colon. If a diet is low in fiber, the colon must exert more pressure than
usual to move small, hard stool. A low-fiber diet also can increase the time
stool remains in the bowel, adding to the high pressure.
may form when the high pressure pushes against weak spots in the colon. Weak spots are where
blood vessels pass through the muscle layer of the bowel wall to supply blood
to the inner wall.
occurs when the blood vessel going to the pouch breaks open.
What are the symptoms?
usually causes sudden, severe bleeding from the rectum. The blood may be dark
red or bright red clots. In most cases there is no pain, and the bleeding stops
on its own.
How is diverticular bleeding diagnosed?
Diverticular bleeding is diagnosed by ruling out other causes of the
bleeding. Your doctor will do a medical history and physical exam, along
with some tests. Imaging tests such as angiography (also known as
arteriography) may be done to find the location of
Colonoscopy—the inspection of the entire large
intestine (colon) using a long, flexible, lighted viewing scope (colonoscope)—is thought to be one of the most useful tests for finding the source of
bleeding in the lower intestines.
Your doctor might do a test
called a technetium-labeled red blood cell bleeding scan to look for the source
of bleeding. In this test, some blood is taken from you, and a small amount of
radioactive material called technetium is added to the blood. The blood
containing the technetium is then injected back into your bloodstream and
traced to the source of bleeding.
How is it treated?
Bleeding from diverticula often
will stop on its own. If it does not, treatment may be needed to stop it and to
replace lost blood, and you may need to be hospitalized. Treatment may include
intravenous fluids, blood transfusions, injection of medicines, and in some
cases surgery to remove the diseased part of the colon.
Can diverticular bleeding be prevented?
high-fiber diet, getting plenty of fluid, and exercising regularly may help
prevent the formation of diverticula. But if you already have diverticulosis,
diet may not help prevent bleeding.
You may have a higher risk of diverticular bleeding if you take aspirin regularly (more than 4 days a week).1
Other Places To Get Help
American College of
6400 Goldsboro Road
Bethesda, MD 20817
The American College of Gastroenterology is an organization of digestive disease specialists. The website contains information about common gastrointestinal problems.
American Society of Colon and Rectal
85 West Algonquin Road
Arlington Heights, IL 60005
The American Society of Colon and Rectal Surgeons is the leading
professional society representing more than 1,000 board-certified colon and
rectal surgeons and other surgeons dedicated to treating people with diseases
and disorders affecting the colon, rectum, and anus.
National Digestive Diseases Information Clearinghouse
2 Information Way
Bethesda, MD 20892-3570
This clearinghouse is a service of the U.S. National
Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the
U.S. National Institutes of Health. The clearinghouse answers questions;
develops, reviews, and sends out publications; and coordinates information
resources about digestive diseases. Publications produced by the clearinghouse
are reviewed carefully for scientific accuracy, content, and readability.
Strate LL, et al. (2011). Use of aspirin or nonsteroidal anti-inflammatory drugs increases risk for diverticulitis and diverticular bleeding. Gastroenterology, 140(5): 1427–1433.
Other Works Consulted
Travis AC, Blumberg RS (2012). Diverticular disease of the colon. In NJ Greenberger et al., eds., Current Diagnosis and Treatment: Gastroenterology, Hepatology, and Endoscopy, 2nd ed., pp. 259–272. New York: McGraw-Hill.
Primary Medical Reviewer
Adam Husney, MD - Family Medicine
Specialist Medical Reviewer
Jerome B. Simon, MD, FRCPC, FACP - Gastroenterology
How this information was developed to help you make better health decisions.