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What do I need to know about Irritable Bowel Syndrome?

Irritable bowel syndrome (IBS) is a “syndrome,” meaning a group of symptoms. The most common symptoms of IBS are abdominal pain or discomfort often reported as cramping, bloating, gas, diarrhea, and/or constipation. IBS affects the colon, or large bowel, which is the part of the digestive tract that stores stool.

IBS is not a disease. It’s a functional disorder, meaning that the bowel doesn’t work, or function, correctly.


Doctors are not sure what causes IBS. The nerves and muscles in the bowel appear to be extra sensitive in people with IBS. Muscles may contract too much when you eat. These contractions can cause cramping and diarrhea during or shortly after a meal. Or the nerves may react when the bowel stretches, causing cramping or pain.

IBS can be painful. But it does not damage the colon or other parts of the digestive system. IBS does not lead to other health problems.



The main symptoms of IBS are

  • abdominal pain or discomfort in the abdomen, often relieved by or associated with a bowel movement

  • chronic diarrhea, constipation, or a combination of both

Other symptoms are

  • whitish mucus in the stool

  • a swollen or bloated abdomen

  • the feeling that you have not finished a bowel movement

Women with IBS often have more symptoms during their menstrual periods.


The doctor may suspect that you have IBS because of your symptoms. Specific symptoms, called the Rome criteria, can be used to more accurately make this diagnosis. Medical tests may also be done to make sure you don’t have any other health problems that cause the same symptoms.

Medical Tests for IBS In addition to a physical exam and blood tests, the following tests might be done to diagnose IBS:

  • Lower gastrointestinal (GI) series. This test uses x rays to diagnose problems in the large intestine. It is also called a barium enema x ray. Before you have the x ray, the doctor will put barium into your large intestine through the anus—the opening where stool leaves the body. Barium is a thick liquid that makes your intestines show up better on the x ray.

  • Colonoscopy. For this test the doctor inserts a long, thin tube, called a colonoscope, into your anus and up into your colon. The tube has a light and tiny lens on the end. The doctor can view the inside of your colon on a big television screen. In some cases, a shorter tube, called a flexible sigmoidoscope, is used to look at just the lower portion of the colon.


IBS has no cure, but you can do things to relieve symptoms. Treatment may involve

  • diet changes

  • medicine

  • stress relief

You may have to try a few things to see what works best for you. Your doctor can help you find the right treatment plan.

Some foods and drinks make IBS worse.
Foods and drinks that may cause or worsen symptoms include

  • fatty foods, like french fries

  • milk products, like cheese or ice cream

  • chocolate

  • alcohol

  • caffeinated drinks, like coffee and some sodas

  • carbonated drinks, like soda

To find out which foods are a problem, keep a diary that tracks

  • what you eat during the day

  • what symptoms you have

  • when symptoms occur

  • what foods always make you feel sick

Some foods make IBS better.
Fiber may reduce the constipation associated with IBS because it makes stool soft and easier to pass. However, some people with IBS who have more sensitive nerves may feel a bit more abdominal discomfort after adding more fiber to their diet. Fiber is found in foods such as breads, cereals, beans, fruits, and vegetables.

Eat small meals.
Large meals can cause cramping and diarrhea in people with IBS. If this happens to you, try eating four or five small meals a day instead of less-frequent big meals.

The doctor may give you medicine to help with symptoms.

  • Laxatives treat constipation. Many kinds of laxatives are available. Your doctor can help you find the laxative that is right for you.

  • Antispasmodics control spasms in the colon and help ease abdominal pain.

  • Antidepressants, even in lower doses than are used for treating depression, can help people with IBS. They can help reduce the abdominal discomfort or pain associated with IBS and, depending on the type chosen, may help the diarrhea or constipation.

Another drug is sometimes prescribed for the treatment of IBS. Alosetron hydrochloride (Lotronex) is for women with severe IBS whose main symptom is diarrhea. Because it can cause serious side effects, Lotronex is only used if other medicines do not work.

You need to follow your doctor’s instructions when you use the medicine. Otherwise, you may need to keep taking it in order to have a bowel movement. Talk with your doctor about potential side effects and what to do if you experience them.


Emotional stress does not cause IBS. But people with IBS may have their bowels react more to stress. So, if you already have IBS, stress can make your symptoms worse.

Stress Relief
Learning to reduce stress can help with IBS. With less stress, you may find you have less cramping and pain. You may also find it easier to manage your symptoms.

Points to Remember

  • IBS means your bowel doesn’t work the right way.

  • IBS can cause cramping, bloating, gas, diarrhea, and constipation.

  • IBS doesn’t damage the bowel or lead to other health problems.

  • The doctor will diagnose IBS based on your symptoms. You may need to have medical tests to rule out other health problems.

  • Stress doesn’t cause IBS, but it can make your symptoms worse.

  • Fatty foods, milk products, chocolate, alcohol, and caffeinated and carbonated drinks can trigger symptoms.

  • Eating foods with fiber and eating small meals throughout the day may reduce symptoms.

  • Treatment for IBS may include medicine, stress relief, and changes in eating habits.

For More Information

International Foundation for Functional Gastrointestinal Disorders
P.O. Box 170864
Milwaukee, WI 53217–8076
Phone: 1–888–964–2001 or 414–964–1799
Fax: 414–964–7176

National Digestive Diseases Information Clearinghouse
2 Information Way
Bethesda, MD 20892–3570
Phone: 1–800–891–5389
Fax: 703–738–4929

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