Diverticulitis: Causes, Risks, & Treatment


What is diverticulitis?


  1. Diverticulitis occurs when the bulging sacs that appear in the lining of your large intestine, or colon, get acutely infected or inflamed.
  2. The most common and severe symptom is sudden pain on the lower left side of the abdomen.
  3. Drinking plenty of water and eating fiber-rich foods can help you avoid diverticulitis.

Diverticula are bulging sacs or small blisters that appear in the lining of your large intestine, or colon. This condition is called diverticulosis when the sacs first appear but aren’t yet inflamed or infected. When these sacs get acutely infected or inflamed, it’s called diverticulitis.

Diverticula are most common in the large intestine. However, they can develop anywhere in your digestive tract. Pain in the lower left side of your abdomen may indicate diverticulitis, especially when it’s accompanied by rectal bleeding. This condition is treatable, but it can recur. Diverticulosis and recurring attacks of diverticulitis are the two components of diverticular disease.

What causes diverticulitis?


No one knows exactly what causes diverticula, but eating a diet that’s low in fiber is thought to contribute to the formation of the sacs. Eating fiber with proper hydration helps soften your stool. Soft stools are easier to pass.

A low-fiber diet can cause problems such as constipation. With constipation, more pressure is needed to pass your stool. Doctors believe that increased colon pressure can lead to the development of diverticula. Diverticulitis occurs when fecal matter lodges in the diverticula and causes infections.

Am I at risk for developing diverticulitis?

Risk Factors

Not eating enough fiber

Not eating enough fiber is a common problem in countries where much of the population eats processed foods. This includes the United States.

Taking fiber supplements or eating more fresh vegetables and bran products can help. You should try to consume at least 20 to 25 grams of fiber per day, which is roughly 5 servings of fruits, vegetables, beans, and whole grains.


Constipation puts strain on your muscles during a bowel movement. Constant strain can increase your risk of developing diverticula in your colon. Once diverticula appear, it’s much more likely that bacterial infections or stool can get into the diverticula and inflame or infect them, causing diverticulitis.


Being obese increases your risk of getting diverticulitis. One study concluded that a high body mass index (BMI) and waist circumference contributed to diverticular bleeding and diverticulitis.


One-third of Americans over the age of 60 will develop diverticulitis, according to Harvard Health Publications. It’s not known why age makes you more susceptible to diverticulitis. However, it could be related to the weakening of the bowels over time.

What are the symptoms of diverticulitis?


Sudden pain on the lower left side of the abdomen is the most common and most severe sign of diverticulitis. This pain can get worse over a few days.

Other signs of diverticulitis are:

  • abdominal pain and tenderness, usually on the lower left side
  • nausea
  • vomiting
  • constipation
  • fever
  • gas or bloating
  • diarrhea
  • loss of appetite
  • rectal bleeding that’s usually bright red

When do I see my doctor?

when to see a doctor

See your doctor to get tested for diverticulitis if you have intense abdominal pain. This is particularly important if the pain’s limited to your lower left side. Blood in your stool or unusual nausea and vomiting also indicate that you should see your doctor.

These symptoms may not be related to diverticulitis, but they are abnormal. Your doctor should conduct tests to either diagnose your diverticulitis or rule it out as a cause.

How is diverticulitis diagnosed?


Your doctor starts your diagnosis by talking to you about your symptoms and your medical history. Your doctor also performs a physical exam, checking for pain in the abdomen. They may check for blood in your stool.

A blood test might also be necessary to find out if your white blood cell count is higher than normal. This can indicate an infection. Your doctor might also order a CT scan to check for infected diverticula. A CT scan uses computer-guided X-ray images.

How is diverticulitis treated?


Depending on your case, your doctor might suggest that you treat yourself at home or recommend that you stay in a hospital during treatment.

Treatment at home

Treatment at home can include:

  • bed rest, which can vary from a few days to a week or more
  • a liquid diet to allow your bowels to rest and your diverticula to heal
  • prescription antibiotics, such as ciprofloxacin (Cipro), levofloxacin (Levaquin), or metronidazole (Flagyl)

Treatment at the hospital

If you’ve developed any complications, your doctor may think it’s best for you to receive hospital treatment. Complications can include a blockage in the bowels or an abscess (a sac filled with pus). While in the hospital, you’ll receive intravenous (IV) antibiotics. If you have an abscess, your doctor will drain it using a needle.

Hospital treatments usually take one to two days. In rare cases, you may need to stay longer so that your doctor can monitor your treatment. Full recovery from a hospital stay usually takes a few weeks. Or it may take a few months based on your diet and lifestyle after the treatment.


Sometimes, diverticulitis recurs often or your infections won’t respond to antibiotics. Your doctor might suggest surgery to remove the part of your intestine that contains the infected diverticula. After surgery, you may need to stay in the hospital for several days, a week, or more. Full recovery may take several months. This is based on your treatment plan and lifestyle changes to help prevent your diverticulitis from returning.

What are the complications of diverticulitis?

Complications Icon

Complications occur in around 25 percent of people who get diverticulitis. Complications can include:

  • a fistula, an abnormal opening between parts of your bowels or between the bladder and your bowels
  • peritonitis, a rupturing of the diverticular pouch that causes the material in your bowels to enter your abdominal cavity

Seek medical attention right away if you experience peritonitis. This condition is serious and can lead to blood infections or organ failure.

What happens after treatment?


Most diverticulitis treatments work well, but diverticula remain in your intestines for the rest of your life. This means that you can develop diverticulitis again at any time.

Lifestyle changes can help you avoid diverticulitis. Drinking plenty of water and adding fiber to your diet are important ways to prevent constipation.

Some people report that eating foods with nuts or seeds, such as peanuts, raspberries, or tomatoes, can cause flare-ups. There is no medical basis for these claims. Your best options are to monitor your responses to food in addition to adding an adequate amount of fiber. The Mayo Clinic recommends that women eat at least 21 to 25 grams of fiber a day. Men should have 30 to 38 grams of fiber each day. 

Add fiber to your diet slowly by eating more fresh fruits and vegetables, such as:

  • pears
  • apples
  • oranges
  • bananas
  • mangos
  • carrots
  • broccoli
  • beets
  • collard greens
  • spinach
  • raspberries
  • sweet potatoes with the skin on
  • black beans
  • kidney beans
  • whole grains or cereals with 5 or more grams of fiber per serving

Going to the bathroom when you feel the urge is also important for avoiding constipation. Waiting too long before going to the bathroom can cause your stool to harden, which can increase the pressure in your bowels.

Exercising for at least 30 minutes a day can also help stop the development of diverticulitis. Regular exercise relieves pressure in your bowels and keeps your bowel movements regular.


You asked, we answered

  • What alternative remedies have been shown to help diverticulitis?
  • Once a diagnosis of diverticulitis has been made — in other words, an infection of the diverticula — it’s best to have bowel rest and antibiotics. Alternative remedies such as a cleansing enema may help evacuate the rectum of any stool and perhaps allow for some symptom relief. Nevertheless, this is not a substitute for proper treatment of an active infection of the diverticula. Other alternative treatments for diverticulitis such as drinking aloe vera juice or taking vitamin C supplements are not sufficient.

    - Modern Weng, D.O.
  • Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

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