Irritable Bowel Syndrome

What is irritable bowel syndrome?

Irritable bowel syndrome (IBS) is a chronic (long-lasting) disorder of the large intestine. (The large intestine is also called the colon or bowel.) IBS is not a disease. It's a condition in which the bowel doesn't work as it should. Although IBS can cause much distress, it does not damage the bowel and does not lead to life-threatening illness.

IBS is the most common intestinal disorder. It affects twice as many women as men and usually begins in early adult life.

How does it occur?

The cause of IBS is not fully understood. With IBS, the nerves and muscles in the bowel are extra sensitive. For example, the muscles may contract too much when you eat. These contractions can cause cramping and diarrhea during or shortly after a meal. Sometimes an abnormal contraction delays bowel movements, causing cramps and constipation.

Some foods may trigger attacks. Sometimes the symptoms of IBS may be triggered by another illness such as stomach flu or other infections causing diarrhea. They may also be triggered by emotional stress or depression because muscles in the bowel are controlled by the nervous system.

What are the symptoms?

The most common symptoms include:

cramping and pain in the abdomen, which may be mild or severe
constipation or diarrhea
a lot of gas.

Other symptoms include:

bloating
a feeling of fullness in the rectum.

Symptoms often occur after you have eaten a big meal or when you are under stress. Women may have more symptoms during their menstrual periods. Your symptoms may be relieved by having a bowel movement.

How is it diagnosed?

After taking your medical history, your health care provider will examine your abdomen and may do a rectal exam.

There is no specific test for IBS. The diagnosis is usually based on your symptoms. But your provider may do these simple tests:

blood tests
tests of bowel movement samples to check for blood and infection.

Depending on your medical and family history, physical exam, and age, your provider may do the following tests to look for other possible causes of your symptoms:

colonoscopy or sigmoidoscopy (procedures that allow your provider to see the inside of your colon with a thin, flexible, lighted tube)
barium enema (a procedure in which a special liquid is passed into the colon through the rectum before x-rays are taken) to check the colon lining.

Your health care provider may ask you to try a milk-free diet to see if lactose intolerance (trouble digesting milk) may be causing your symptoms.

How is it treated?

Doctors have not yet found a cure for IBS. However, controlling the diet and emotional stress usually relieves the symptoms. Some medicines may also help.

Diet

Increasing the fiber in your diet often helps, although sometimes a decrease in fiber is needed. Try eating smaller meals more often. Avoid foods that cause gas, such as cabbage. Other foods that may cause symptoms are:
- fatty foods, such as French fries
- milk products, such as cheese or ice cream
- chocolate
- caffeine (found in coffee and some sodas)
Food diary

Your health care provider may ask you to keep a food diary to see if eating a particular food, for example, milk, worsens your symptoms.
Stress

Your provider will help you identify things that cause stress in your life and will suggest ways to help you control them. Relaxation or biofeedback techniques may help you manage stress.
Medicines

Your provider may prescribe:
- Bulk-forming agents, such as bran or methylcellulose
- Antispasmodic drugs to slow contractions in the bowel and help with diarrhea and pain
- Antidepressants, which can help control chronic pain
- Serotonin-related medicines to help with constipation or diarrhea: Tegaserod (Zelnorm) is a short-term treatment for constipation in women who have IBS. Alosetron is a new medicine for treatment of IBS when diarrhea is the main symptom.

How long will the effects last?

Because IBS is a chronic disorder, you may have flare-ups of symptoms throughout your life. Although a cure hasn't been found yet, the disorder can usually be controlled. IBS will not progress to something worse.

How can I take care of myself?

Follow your health care provider's recommendations.
Learn stress-management techniques to reduce stress and anxiety in your life. Professional counseling may be helpful.
Exercise regularly, according to your provider's recommendations. Exercise helps keep bowel movements regular. It may also help maintain serotonin levels in the brain.
Drink plenty of water.
Do not drink alcohol, which can make symptoms of IBS worse.
Select your foods carefully. If a food appears to bring on your symptoms, avoid it. However, don't eliminate a food just because it appears to cause symptoms one time. Be sure that a food produces symptoms several times before you give it up. You should try to keep many different foods in your diet because a varied diet provides better nutrition.
Ask your health care provider if you should have a high-fiber diet, especially if you tend to be constipated. High-fiber foods may cause gas and bloating, but usually these symptoms lessen as the digestive tract gets used to the increased fiber. Some high-fiber foods include:
- whole-grain breads and cereals
- fruits, especially apricots, blackberries, coconut, dates, figs, kiwi, peaches, pears, pineapple, prunes, raspberries, and strawberries
- nuts, especially almonds, pistachios, and walnuts
- vegetables, particularly Brussels sprouts, corn and popcorn, broccoli, and parsley
- beans and lentils.
Ask your health care provider if you should use a nonprescription fiber supplement.
Eat smaller meals more often. For example, eat 6 small meals a day rather than 3 large ones.
See your health care provider if your symptoms are getting worse or you are having them more often.

Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available. The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.

HIA File DIG4031F.HTM Release 9.0/2006