What is diverticulitis?
What causes diverticulitis?
Doctors aren't sure what causes diverticulitis. 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.
Diverticulitis happens when bacteria get trapped in the pouches. This can lead to inflammation or infection.
What are the symptoms?
Symptoms of diverticulitis may last from a few hours to a week or more. Symptoms include:
- Belly pain, usually in the lower left side, that is sometimes worse when you move. This is the most common symptom.
- Fever and chills.
- Bloating and gas.
- Diarrhea or constipation.
- Nausea and sometimes vomiting.
- Not feeling like eating.
How is diverticulitis diagnosed?
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 may include:
- Blood tests, such as a complete blood count (CBC).
- Other tests, such as an X-ray, a CT scan, or a colonoscopy.
How is it treated?
The treatment you need depends on how bad your symptoms are and whether you have an infection. You may need to have only liquids at first, and then return to solid food when you start feeling better.
If you have an infection, your doctor may prescribe antibiotics. Take them as directed. Do not stop taking them just because you feel better.
For mild cramps and belly pain:
- Use a heating pad, set on low, on your belly.
- Relax. For example, try meditation or slow, deep breathing in a quiet room.
- Take medicine, such as acetaminophen (Tylenol, for example).
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).
How can you prevent diverticulitis?
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.
Frequently Asked Questions
Learning about diverticular disease:
Diverticulitis develops when bacteria become trapped in pouches (diverticula) that have formed along the wall of the large intestine, leading to an infection. The bacteria grow and cause inflammation and pressure that 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) cavity.
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, adding 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 wall.
It is not known why some people who have these diverticula (a condition called diverticulosis) develop diverticulitis and others do not.
Symptoms of diverticulitis may last from a few hours to several days. These symptoms may include:
- Tenderness, cramps, or pain in the abdomen (usually in the lower left side but may occur on the right) that is sometimes worse when you move.
- Fever and chills.
- A bloated feeling, abdominal swelling, or gas.
- Diarrhea or constipation.
- Nausea and sometimes vomiting.
- Loss of appetite.
Complications also can cause symptoms. If an abnormal opening (fistula) develops between the colon and the vagina or the colon and the urethra, you may pass air or stool from the vagina or the urethra.
Other conditions, such as irritable bowel syndrome (IBS) or a urinary tract infection, may cause symptoms similar to diverticulitis. Symptoms such as rectal bleeding, a change in bowel habits, and unexplained weight loss may be signs of colon cancer. If you have any of these symptoms, contact your doctor.
Diverticulitis develops 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% of people who have these pouches—a condition called diverticulosis—develop diverticulitis and the others do not.
Diverticulitis usually affects the left side of the colon (sigmoid colon).
Mild attacks of diverticulitis, with few symptoms or signs of infection or inflammation, sometimes heal without treatment. In some 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 resting the bowel with fluids given through a vein (intravenous, or IV) or a liquid diet and taking IV antibiotics. If severe diverticulitis is not treated, complications such as an abscess or fistula may develop. Surgery often is needed to treat complications.
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.1
What Increases Your Risk
The possibility of developing diverticulitis increases with age.
You may be more likely to develop diverticulitis if you:
- Eat a low-fiber diet.
- Have a family history of diverticulosis.
When To Call a Doctor
Call 911 or other emergency services immediately if the person has been bleeding from the anus and has signs of shock, which could indicate that a diverticular pouch is bleeding (diverticular bleeding).
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:
- Fever or chills.
- Nausea and vomiting.
- Unusual changes in your bowel movements or abdominal swelling.
- Blood in your stool.
- Pain that is worse when you move.
- Burning pain when you urinate.
- Abnormal vaginal discharge.
Call your doctor immediately if you have:
- Severe pain in the abdomen that is getting worse.
- Pain in the abdomen that becomes worse when you move or cough.
- A stool that is mostly blood (more than a few streaks of blood on the stool). Blood in the stool may appear as reddish or maroon-colored liquid or clots or may produce a black stool that looks like tar.
- Shoulder pain (possibly from air in the abdomen due to a hole or perforation in the intestine).
- Pass gas or stool from your urethra while urinating. This likely means that you have an opening (fistula) between the bowel and the urinary tract.
Call your doctor if you:
- Have cramping pain that does not get better when you have a bowel movement or pass gas.
It is not uncommon to have bloating, gas pressure, or mild abdominal 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 doctor.
Who To See
Health professionals who can diagnose and prescribe treatment for diverticulitis include:
- Family medicine physician , general practitioner, or other primary care doctor.
- Internist .
- Physician assistant .
- Nurse practitioner .
If further tests are needed, if your symptoms do not respond to treatment, or if you may need surgery, your health professional may refer you to a:
To prepare for your appointment, see the topic Making the Most of Your Appointment.
Exams and Tests
Your doctor will take a history and give you a physical examination 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.
- Complete blood count (CBC) may show if you have an infection or if you have too few red blood cells in your blood, possibly because of bleeding in the colon.
- Urinalysis may show you have a urinary tract infection.
- Abdominal X-ray may provide clues about the cause of abdominal pain and other symptoms.
- The digital rectal exam looks for tenderness or a mass in the lower pelvic area.
- The fecal occult blood test looks for blood in your stool.
Tests done as needed
Depending on your symptoms, your doctor may want to do one or more of these tests.
- A computed tomography (CT) scan may be done if symptoms suggest you have a pocket of infection (abscess) in your abdomen or that a pouch (diverticulum) has burst. The scan also can reveal other possible causes of your symptoms.
- A barium enema X-ray may be used to show diverticula or other possible causes of your symptoms. But a barium enema X-ray usually is not done while you are having an attack of diverticulitis because of the risk that the barium might spill into the peritoneum (the lining of the abdominal cavity) if you have a perforation. A material that performs a function similar to barium but that can dissolve in water (water-soluble contrast) may be used instead. See barium enema images of a normal colon and of diverticulosis.
- Flexible sigmoidoscopy and colonoscopy may be used if your main symptom is bleeding from the intestine. These tests also may be done to look for narrow spots or growths in the intestine and to rule out ulcerative colitis or cancer.
- An upper gastrointestinal (UGI) series may be done to find out whether your symptoms may be caused by a problem in your stomach or small intestine.
- An upper gastrointestinal endoscopy may be done to find out whether your symptoms are caused by a problem in your stomach or the upper part of your small intestine.
If you are having serious bleeding from the intestine, a condition called diverticular bleeding, your doctor may want to do:
- A technetium-labeled red blood cell bleeding scan, to find the source of bleeding.
- Angiogram (also called arteriogram), to locate the source of bleeding if you are having a large amount of bleeding in your intestine.
See the topic Diverticular Bleeding for more information.
No screening is available for diverticulitis at this time. But diverticula may be found during a regular screening for colon cancer. Recommendations for colon cancer screening include flexible sigmoidoscopy every 5 years or a colonoscopy every 10 years after the age of 50. Both flexible sigmoidoscopy and colonoscopy involve using a flexible tube with a lighted viewing instrument to see inside the large intestine. These exams often reveal diverticula if they are present.
You may have a brief (acute) bout of diverticulitis that goes away with home treatment such as increasing fiber in your 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 develop.
- Medicines such as antibiotics and pain relievers.
- Changes in diet, starting with a clear-liquid or bland diet that is low in fiber until the pain goes away, then increasing the amount of fiber.
Although some people avoid nuts, seeds, berries, and popcorn, believing that these foods might get trapped in the diverticula and cause pain, there is no evidence that they cause or worsen diverticulitis.2
If the pain is severe, you are not able to drink liquids, or you have complications of diverticulitis, hospitalization is necessary. Treatment will include:
- Receiving antibiotics in a vein (intravenous, or IV).
- Receiving intravenous fluids and nutrition only (no food or drink by mouth) for up to a week to allow the bowel to rest.
- Keeping the stomach empty by sucking out the contents through a tube passed up the nose and down the throat into the stomach (nasogastric or NG tube). This may be needed if you are vomiting or have abdominal swelling.
- Performing surgery either for complications of diverticulitis or if you have had repeated attacks that are not helped by changing your diet. Overall, fewer than 6 out of 100 people with diverticulitis need surgery.3
Most cases of promptly treated diverticulitis will improve in 2 to 3 days.
Treatment after recovery from an attack of diverticulitis is aimed at preventing another attack. Treatment may include:
- Gradually increasing the amount of fiber in the diet through fruits, vegetables, wheat bran, and possibly the regular use of a fiber supplement.
- Getting plenty of fluids daily.
- Having regular doctor visits to monitor your condition. If you have diverticulitis, the doctor may see you about 2 days after treatment begins to make sure you are improving. A colonoscopy or barium enema X-ray probably will be done about 6 weeks later, after symptoms are under control, to look for any other problems, such as inflammatory bowel disease or colon cancer.
Treatment if the condition gets worse
In some cases, complications of diverticulitis, such as an abscess, perforation, or bowel obstruction, can develop. Surgery to remove the affected part of the intestine usually is needed to treat these conditions.
Nonurgent (elective) surgery also may be done for diverticulitis if you have had two or more severe attacks, which usually indicates a greater chance of having future attacks.4
To help prevent diverticulitis:
- Eat a high-fiber diet that is low in fat and red meat.
- Drink plenty of water.
- Exercise regularly.
Home treatment may help you control symptoms of diverticulitis or reduce the chance of having additional attacks of diverticulitis.
To reduce abdominal pain caused by mild diverticulitis:
- Apply a heating pad to your abdomen to relieve mild cramps and pain.
- Try relaxation techniques (such as slow, deep breathing in a quiet room or meditation) to help reduce mild pain.
- Use a nonprescription pain medicine such as acetaminophen (for example, Tylenol).
- If these techniques do not help and your pain increases, call your doctor to see whether prescription pain medicine is needed.
When you are feeling better, you can do some things to help prevent another attack. You may want to:
- Eat a high-fiber diet. Whole-grain breads and cereals, brown rice, and fresh fruits and vegetables can all be part of a high-fiber diet.
- Practice healthy bowel habits, such as eating at regular times, not straining during a bowel movement, and getting plenty of fluids each day.
- Try not to rely on laxatives to have regular bowel movements.
Medications to stop infection and to control symptoms often are used to treat attacks of diverticulitis.
- Antibiotics (such as metronidazole and ciprofloxacin) are given to treat the infection causing the attack.
- Prescription pain relievers sometimes are needed if nonprescription pain relievers cannot control the pain.
What To Think About
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. For more information, see the Prevention and Home Treatment sections of this topic.
Surgery for diverticulitis involves removing the diseased part of the colon. You may decide to have surgery for diverticulitis if you have:
- A partially blocked colon or a narrow spot in the colon (stricture).
- Repeated attacks of diverticulitis. Surgery to remove the diseased part of the colon often is recommended if you have two or more severe attacks.
- A high risk of complications (such as people younger than age 40 who have had an attack of diverticulitis).
- Repeated problems with bleeding from the colon.
- An abnormal opening (fistula) that has formed between the colon and an adjacent organ, most commonly the bladder, uterus, or vagina.
- Signs of possible cancer that cannot be confirmed with other tests.
Surgery for diverticulitis, in which the infected part of the colon is removed, may be required if you have complications, including:
- An infected pouch (diverticulum) that has ruptured into the abdominal cavity, especially if a pocket of infection (abscess) has formed. In some cases, an abscess can be drained without surgery. (See the Other Treatment section of this topic.)
- An infection that has spread into the abdominal cavity (peritonitis).
- A blocked colon (bowel obstruction).
- Infection that has spread through the blood to other parts of the body (sepsis).
- Severe bleeding that does not stop with treatment given through an angiogram or colonoscopy.
Overall, fewer than 6 out of 100 people with diverticulitis need surgery.3
Surgical treatment 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. The colostomy is usually removed and the intestine reconnected at a later time.
Surgical treatment of diverticulitis, called partial colectomy, involves the removal of the diseased part of the large intestine.
What To Think About
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 diet.
If you have multiple attacks of diverticulitis, surgery may be appropriate.
The survival rate is 99% for nonurgent (elective) surgery for diverticulitis.4 An emergency surgery has more risks.
Draining an abscess. 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.
Bowel rest. 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 digestive juices.
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.
Other Places To Get Help
|American Society of Colon and Rectal Surgeons|
|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 (NDDIC)|
|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.
- Humes D, et al. (2008). Colonic diverticular disease, search date March 2007. Online version of BMJ Clinical Evidence. Also available online: http://www.clinicalevidence.com.
- Davis BR, Matthews JB (2006). Diverticular disease of the colon. In M Wolfe et al., eds., Therapy of Digestive Disorders, 2nd ed., pp. 855–859. Philadelphia: Saunders Elsevier.
- Harford WV (2005). Diverticulosis, diverticulitis, and appendicitis. In DC Dale, DD Federman, eds., ACP Medicine, section 4, chap. 12. New York: WebMD.
- Stabile BE, Arnell TD (2003). Diverticular disease of the colon. In SL Friedman et al., eds., Current Diagnosis and Treatment in Gastroenterology, 2nd ed., pp. 436–451. New York: McGraw-Hill.
Other Works Consulted
- Fox JM, Stollman NH (2006). Diverticular disease of the colon. In M Feldman et al., eds., Sleisenger and Fordtran's Gastrointestinal and Liver Disease, 8th ed., vol. 2, pp. 2613–2632. Philadelphia: Saunders Elsevier.
|Editor||Kathleen M. Ariss, MS|
|Associate Editor||Pat Truman, MATC|
|Primary Medical Reviewer||Kathleen Romito, MD - Family Medicine|
|Specialist Medical Reviewer||Jerome B. Simon, MD, FRCPC, FACP - Gastroenterology|
|Last Updated||July 30, 2008|
Last Updated: July 30, 2008
Author: Monica Rhodes