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Diverticulosis happens when pouches (diverticula) form in the wall of the colon. If these pouches get inflamed or infected, it is called diverticulitis. Diverticulitis can be very painful.
Doctors aren't sure
what causes diverticula in the colon (diverticulosis). But they think that a low-fiber diet may play a
role. Without fiber to add bulk to the stool, the colon has to work harder than
normal to push the stool forward. The pressure from this may cause pouches to
form in weak spots along the colon.
Doctors aren't sure what causes diverticulitis. Bacteria grow in the pouches, and this can lead to inflammation or infection.
Symptoms of diverticulitis
may last from a few hours to a week or more. Symptoms include:
Your doctor will
ask about your symptoms and will examine you. He or she may do tests to see if
you have an infection or to make sure that you don't have other problems. Tests
The treatment you need depends
on how bad your symptoms are. You may need to
have only liquids at first, and then return to solid food when you start
feeling better. Your doctor will give you medicines for pain and antibiotics. Take the antibiotics as directed. Do not stop taking them just
because you feel better.
For mild cramps and belly pain:
You may need surgery only if diverticulitis doesn't get
better with other treatment, or if you have problems such as long-lasting
(chronic) pain, a bowel obstruction, a
fistula, or a pocket of infection (abscess).
You may be
able to prevent diverticulitis if you drink plenty of water, get regular
exercise, and eat a high-fiber diet. A high-fiber diet includes whole grains,
fresh fruits, and vegetables.
Learning about diverticular disease:
Doctors aren't sure what causes diverticulitis. Bacteria grow in the pouches (diverticula), and this can lead to inflammation or infection. Pressure may lead to a small
perforation or tear in the wall of the intestine.
Peritonitis, an infection of the lining of the
abdominal wall, may develop if infection spills into the abdominal (peritoneal)
The reason diverticula form in the wall of the large
intestine (colon) is not completely understood. Doctors think diverticula form
when high pressure inside the colon pushes against weak spots in the colon
wall. Uncoordinated movements of the colon can also contribute to the
development of diverticula.
Normally, a diet with adequate 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. This adds to the high pressure. Pouches may form when
the high pressure pushes against weak spots in the colon where blood vessels
pass through the muscle layer of the bowel wall to supply blood to the inner
It is not known why some people who have these diverticula
(a condition called
diverticulosis) develop diverticulitis and others do
diverticulitis may last from a few hours to several
days. These symptoms may include:
Complications also can cause symptoms. If an abnormal
opening (fistula) develops between the colon and the vagina or the colon and
urethra, you may pass air or stool from the vagina or
Other conditions, such as
irritable bowel syndrome (IBS) or a
urinary tract infection, may cause symptoms similar to
occurs when pouches (diverticula) that have developed in the wall of the
large intestine (colon) become inflamed or infected. It is not clearly
understood why 20 out of 100 people who have these pouches—a condition called
diverticulosis—develop diverticulitis and the others
In Western countries (North America and Europe), diverticulitis usually affects the left side of the colon
Mild attacks of diverticulitis, with few symptoms
or signs of infection or inflammation, sometimes heal without treatment. In
most cases, a doctor recommends oral antibiotics to resolve an infection and a
clear liquid diet to rest the bowel until inflammation goes away.
When infection and symptoms are severe, diverticulitis is treated in the
hospital. Treatment includes antibiotics given in a vein
(intravenous, or IV) and resting the bowel with IV fluids. If severe
diverticulitis is not treated,
complications such as an
fistula may develop. Surgery often is needed to treat
It is common to have lower abdominal pain after
recovering from an attack of diverticulitis. But this pain is not always a
return of diverticulitis. Less than half of people ever have a second
diverticulitis attack. Of those who do have another attack, about half have the
second attack within 1 year of their first one.footnote 1
The possibility of
diverticulitis increases with age.
may be more likely to develop diverticulitis if you:
Call 911 or other emergency services immediately if the person has been bleeding from the anus and
has signs of
shock, which could mean that a diverticular pouch
is bleeding (diverticular bleeding). Signs of shock include passing out, or feeling very dizzy, weak, or less alert.
Call your doctor immediately if you have pain in the abdomen
that is in one spot (as opposed to general pain in the abdomen), especially if
you also have:
Call your doctor immediately if you
Call your doctor if you:
Call your doctor if you are treating mild diverticulitis at home and:
It is not uncommon to have bloating, gas
pressure, or mild abdominal (belly) pain. These can be caused by eating certain foods
or by stress. Home treatment usually will take care of these symptoms. If home
treatment does not help or if the symptoms become worse, see your
Health professionals who can diagnose and prescribe treatment for
If further tests are needed, if your symptoms do not
respond to treatment, or if you may need surgery, your doctor may
refer you to a:
To prepare for your appointment, see the topic Making the Most of Your Appointment.
Your doctor will
take a history and do a physical exam if
diverticulitis is suspected. Depending on your
symptoms, you may have one or more tests to rule out other medical problems
that could be causing your symptoms. The extent of testing will depend on how
bad your symptoms are and how long they have lasted.
These tests may be done any time
you see your doctor about abdominal pain or other symptoms.
Depending on your symptoms, your doctor may want to do one or more of
You may have a brief (acute) bout
diverticulitis that goes away after treatment with antibiotics and a liquid diet. But in some cases the condition occurs off
and on (intermittently) over the long term (chronic). Treatment is the same in
both cases, unless complications occur.
diverticulitis depends on how bad your
symptoms are. If the pain is mild, you are able to drink liquids, and you have no
complications, treatment may include:
If the pain is severe,
you are not able to drink liquids, or you have complications of diverticulitis,
a hospital stay is needed. Treatment will include:
Treatment may also include:
Most cases of promptly treated diverticulitis will
improve in 2 to 3 days. If your doctor prescribed antibiotics, take them as directed. Do not stop taking them just because you feel better.
Treatment after recovery from an
diverticulitis is aimed at preventing another attack.
Treatment may include:
complications of diverticulitis, such as an abscess,
perforation, or bowel obstruction, can occur.
Surgery to remove the affected part of the intestine usually is needed to treat
Nonurgent (elective) surgery also may be done
for diverticulitis if you have had two or more severe attacks, are younger than age 40, or have an impaired immune system.
To help prevent
Home treatment may help you control
diverticulitis or reduce the chance of having
additional attacks of diverticulitis.
To reduce abdominal pain
caused by mild diverticulitis:
When you are feeling better, you can do some things to help
prevent another attack. You may want to:
Do not use
laxatives or enemas unless your doctor prescribes them. If you use laxatives too often, you can become dependent on them for bowel movements. If you are having a sudden (acute) attack of diverticulitis, laxatives or enemas can make the pain worse.
Medicines to stop infection and to
control symptoms often are used to treat attacks of
Medicines are not used to
prevent future attacks of diverticulitis. Prevention depends on increasing the
amount of fiber in your diet and practicing healthy bowel habits.
diverticulitis involves removing the diseased part of
the colon. You may decide to have surgery for diverticulitis if you
Surgery for diverticulitis, in which the infected part of
the colon is removed, may be required if you have
Overall, fewer than 6 out of 100 people who have diverticulitis
need surgery.footnote 3
involves removing the diseased part of the large intestine (partial colectomy)
and reconnecting the remaining parts. Depending on the severity and nature of
the symptoms, more than one surgery may be needed to correct the problem. When
multiple surgeries are needed, the person usually has a
colostomy during the time between surgeries. A
colostomy is a surgical procedure in which the upper part of the intestine is
sewn to an opening made in the skin of the abdomen. Stool passes out of the
body at this opening and into a disposable bag. Usually the colostomy is
removed at a later time and the intestine is reconnected.
Surgical treatment of diverticulitis, called
bowel resection, involves the removal of the
diseased part of the large intestine.
People who have mild, brief
attacks and who are willing to try long-term dietary changes may be able to
avoid surgery. See the Prevention section of this topic for more information on
If you have multiple attacks of diverticulitis, surgery may
In some cases of
diverticulitis, a pocket of infection (abscess) in the abdomen heals on its own. At other
times it can be drained without surgery. A needle is passed through the skin
into the abscess, and the liquid containing the infection is drained. A
computed tomography (CT) scan is used to help the
doctor guide the needle into the abscess. Sometimes a plastic drain is placed
temporarily in the abdomen to drain the abscess.
A blocked colon can sometimes be treated with
bowel rest. You are not given anything to eat but instead receive fluids and
nutrients through a tube connected to a vein. Suction through a tube placed in
the nose and down into the stomach may be needed to keep the stomach emptied of
After 2 to 3 days of bowel rest, you are given
something to eat. If the obstruction has cleared up, no surgery is needed. If
the obstruction remains, bowel rest may be continued. If repeated periods of
bowel rest fail to clear up the obstruction, surgery to remove the diseased
part of the colon may be considered.
Humes D, Spiller RC (2016). Colonic diverticular disease: Medical treatments for acute diverticulitis. BMJ Clinical Evidence. http://clinicalevidence.bmj.com/x/systematic-review/0405/overview.html. Accessed April 14, 2016.
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.
Harford WV (2010). Diverticulosis, diverticulitis, and appendicitis. In EG Nabel, ed., ACP Medicine, section 4, chap. 12. Hamilton, ON: BC Decker.
Other Works Consulted
Fox JM, Stollman NH (2010). Diverticular disease of the colon. In M Feldman et al., eds., Sleisenger and Fordtran's Gastrointestinal and Liver Disease, 9th ed., vol. 2, pp. 2073–2089. Philadelphia: Saunders.
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.
ByHealthwise StaffPrimary Medical ReviewerAdam Husney, MD - Family MedicineE. Gregory Thompson, MD - Internal MedicineSpecialist Medical ReviewerJerome B. Simon, MD, FRCPC, FACP - Gastroenterology
Current as ofAugust 9, 2016
Current as of:
August 9, 2016
Adam Husney, MD - Family Medicine & E. Gregory Thompson, MD - Internal Medicine & Jerome B. Simon, MD, FRCPC, FACP - Gastroenterology
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