Irritable bowel syndrome is a disorder characterized most commonly by cramping, abdominal pain, bloating, constipation, and diarrhea. IBS causes a great deal of discomfort and distress, but it does not permanently harm the intestines and does not lead to a serious disease, such as cancer. Most people can control their symptoms with diet, stress management, and prescribed medications. For some people, however, IBS can be disabling. They may be unable to work, attend social events, or even travel short distances.

As many as 20% of the adult population, or one in five Americans, has symptoms of IBS, making it one of the most common disorders diagnosed by doctors. It occurs more often in women than in men, and it begins before the age of 35 in about 50% of people.

What are the symptoms of IBS?

Abdominal pain, bloating, and discomfort are the main symptoms of IBS. However, symptoms can vary from person to person. Some people have constipation, which means hard, difficult-to-pass, or infrequent bowel movements. Often these people report straining and cramping when trying to have a bowel movement but cannot eliminate any stool, or they are able to eliminate only a small amount. If they are able to have a bowel movement, there may be mucus in it, which is a fluid that moistens and protect passages in the digestive system.

Some people with IBS experience diarrhea, which is frequent, loose, watery, stools. People with diarrhea frequently feel an urgent and uncontrollable need to have a bowel movement. Other people with IBS alternate between constipation and diarrhea. Sometimes people find that their symptoms subside for a few months and then return, while others report a constant worsening of symptoms over time.

What causes IBS?

Researchers have yet to discover any specific cause for IBS. One theory is that people who suffer from IBS have a colon, or large intestine, that is particularly sensitive and reactive to certain foods and stress. The immune system, which fights infection, may also be involved.

If you think you have IBS, seeing your doctor is the first step. IBS is generally diagnosed on the basis of a complete medical history that includes a careful description of symptoms and a physical examination.

There is no specific test for IBS, although diagnostic tests may be performed to rule out other problems. These tests may include stool sample testing, blood tests, and x rays. Typically, a doctor will perform a sigmoidoscopy, or colonoscopy, which allows the doctor to look inside the colon. This is done by inserting a small, flexible tube with a camera on the end of it through the anus. The camera then transfers the images of your colon onto a large screen for the doctor to see better.

If your test results are negative, the doctor may diagnose IBS based on your symptoms, including how often you have had abdominal pain or discomfort during the past year, when the pain starts and stops in relation to bowel function, and how your bowel frequency and stool consistency have changed. Many doctors refer to a list of specific symptoms that must be present to make a diagnosis of IBS.

Symptoms include...

• Abdominal pain or discomfort for at least 12 weeks out of the previous 12 months. These 12 weeks do not have to be consecutive.

• The abdominal pain or discomfort has two of the following three features:

  • It is relieved by having a bowel movement.

  • When it starts, there is a change in how often you have a bowel movement.

  • When it starts, there is a change in the form of the stool or the way it looks.

• Certain symptoms must also be present, such as

  • a change in frequency of bowel movements

  • a change in appearance of bowel movements

  • feelings of uncontrollable urgency to have a bowel movement

  • difficulty or inability to pass stool

  • mucus in the stool

  • bloating

• Bleeding, fever, weight loss, and persistent severe pain are not symptoms of IBS and may indicate other problems such as inflammation, or rarely, cancer.

The following have been associated with a worsening of IBS symptoms

• large meals

• bloating from gas in the colon

• medicines

• wheat, rye, barley, chocolate, milk products, or alcohol

• drinks with caffeine, such as coffee, tea, or colas

• stress, conflict, or emotional upsets

Researchers have found that women with IBS may have more symptoms during their menstrual periods, suggesting that reproductive hormones can worsen IBS problems.

In addition, people with IBS frequently suffer from depression and anxiety, which can worsen symptoms. Similarly, the symptoms associated with IBS can cause a person to feel depressed and anxious.

What is the treatment for IBS?

Unfortunately, many people suffer from IBS for a long time before seeking medical treatment. Up to 70 %  of people suffering from IBS are not receiving medical care for their symptoms. No cure has been found for IBS, but many options are available to treat the symptoms. Your doctor will give you the best treatments for your particular symptoms and encourage you to manage stress and make changes to your diet.

Medications are an important part of relieving symptoms. Your doctor may suggest fiber supplements or laxatives for constipation or medicines to decrease diarrhea, such as Lomotil or loperamide (Imodium). An antispasmodic is commonly prescribed, which helps to control colon muscle spasms and reduce abdominal pain. Antidepressants may relieve some symptoms. However, both antispasmodics and antidepressants can worsen constipation, so some doctors will also prescribe medications that relax muscles in the bladder and intestines, such as Donnapine and Librax. These medications contain a mild sedative, which can be habit forming, so they need to be used under the guidance of a physician.

A medication available specifically to treat IBS is alosetron hydrochloride (Lotronex). Lotronex has been reapproved with significant restrictions by the U.S. Food and Drug Administration (FDA) for women with severe IBS who have not responded to conventional therapy and whose primary symptom is diarrhea. However, even in these patients, Lotronex should be used with great caution because it can have serious side effects such as severe constipation or decreased blood flow to the colon.

With any medication, even over-the-counter medications such as laxatives and fiber supplements, it is important to follow your doctor’s instructions. Some people report a worsening in abdominal bloating and gas from increased fiber intake, and laxatives can be habit forming if they are used too frequently.

Medications affect people differently, and no one medication or combination of medications will work for everyone with IBS. You will need to work with your doctor to find the best combination of medicine, diet, counseling, and support to control your symptoms.

Can changes in diet help IBS?

For many people, careful eating reduces IBS symptoms. Before changing your diet, keep a journal noting the foods that seem to cause distress. Then discuss your findings with your doctor. You may want to consult a registered dietitian who can help you make changes to your diet. For instance, if dairy products cause your symptoms to flare up, you can try eating less of those foods. You might be able to tolerate yogurt better than other dairy products because it contains bacteria that supply the enzyme needed to digest lactose, the sugar found in milk products. Dairy products are an important source of calcium and other nutrients. If you need to avoid dairy products, be sure to get adequate nutrients in the foods you substitute, or take supplements.

In many cases, dietary fiber may lessen IBS symptoms, particularly constipation. However, it may not help with lowering pain or decreasing diarrhea. Whole grain breads and cereals, fruits, and vegetables are good sources of fiber. High-fiber diets keep the colon mildly distended, which may help prevent spasms. Some forms of fiber keep water in the stool, thereby preventing hard stools that are difficult to pass. Doctors usually recommend a diet with enough fiber to produce soft, painless bowel movements. High-fiber diets may cause gas and bloating, although some people report that these symptoms go away within a few weeks.

For More Information

International Foundation for Functional Gastrointestinal Disorders
P.O. Box 170864
Milwaukee, WI 53217–8076

Phone: 1–888–964–2001
Fax: 414–964–7176
Email: iffgd@iffgd.org
Internet: www.iffgd.org