Irritable Bowel Syndrome

Newly Diagnosed with IBS

What is it?

The term "irritable bowel syndrome" (often called IBS) refers to a collection of symptoms with no obvious cause. It is not a disease, but a syndrome -- a group of symptoms that occur together. People with IBS seem to have perfectly healthy digestive systems, but they frequently develop cramping pain in the lower abdomen along with either diarrhea or constipation (sometimes alternating bouts of both). Typically, the pain flares up after a meal and goes away after defecation. Many people also experience gas, bloating, small stools, or mucus in the stool. The symptoms tend to come and go and can occur in any combination.

About 10% to 20% of Americans have IBS at some point in their lives, and only the common cold causes more missed work time. Women are twice as likely as men to have the condition.

For many years, doctors thought irritable bowel syndrome was mainly a condition of the mind. After all, these patients always had normal physical exams, and many said they noticed symptoms only during times of stress. Many questions remain, but it's clear that IBS isn't "all in your head." Researchers now suspect the problem springs from a communication breakdown between the nerves and muscles that control the colon.

Without the proper controls, the contractions that move waste through the colon can speed up, leading to painful spasms and diarrhea. Alternatively, the contractions can become sluggish, setting the stage for constipation. The colon also becomes extremely sensitive, and even normal contractions can cause considerable pain.

Stress and anxiety may not cause irritable bowel syndrome, but they can definitely make symptoms worse. Some people also react strongly to certain foods and drinks, especially fatty foods, dairy products, and drinks with alcohol or caffeine.

How do I know I have it?

Doctors can usually diagnose irritable bowel syndrome by taking an inventory of a patient's symptoms and performing a physical exam. They may also want to check the blood or stool for other possible causes of the symptoms, such as parasitic infections or diabetes. Some patients, particularly those over age 50, also need to have their colon examined with a sigmoidoscope or colonoscope to rule out colon cancer and other diseases.

Symptoms of irritable bowel syndrome eventually fade completely for about 30% of patients, but most live with it for the rest of their lives. Fortunately, IBS doesn't damage the bowels, and it doesn't raise the risk of colon cancer or any other disease.

What's the treatment?

There's no single game plan for treating irritable bowel syndrome. But with your doctor's help, you can find an individual approach that works best for your symptoms.

First, the more you know about your condition, the more you can do to help yourself. For this reason, it's a good idea to keep a symptom diary for at least a couple of weeks. Every day, write down your symptoms and what you were doing before they started. Also keep track of food, drinks, and emotions. Then look for patterns. If something reliably causes trouble, you can try to avoid it.

You may find that a simple change of diet works wonders. Many people feel better after cutting some fat from their meals. If you are constipated, increasing your fiber intake to 20 or 30 grams every day can help keep you regular. Doctors used to recommend high-fiber diets for all patients with irritable bowel syndrome, but there's little evidence this helps with anything other than constipation. In fact, a high-fiber diet may worsen gas, bloating, and stomach pain.

If your bouts of IBS seem to go hand-in-hand with stress and anxiety, you may need to learn how to relax and cope with your feelings. Ask your doctor about relaxation techniques or counseling.

If necessary, your doctor can prescribe medications to help control your symptoms. The drugs hyoscyamine (Anaspaz, Cystospaz, Levsin) and dicyclomine (Bentyl) can all ease pain and diarrhea by relaxing the colon. If your pain is intense, or if you also have depression, your doctor may prescribe an antidepressant. When given in smaller doses than those used to treat depression, these medications can help block pain.

Lotronex, which affects how the intestines use the chemical messenger serotonin, has received limited approval for women who suffer from the severe form of IBS that causes diarrhea. It is no longer approved for other patients, because some who took Lotronex experienced severe constipation or reduced blood flow to the large intestine (ischemic colitis). In a few cases, side effects led to surgery to correct the problem. Seven deaths have been linked to the medication.

The drug Zelnorm has also been approved to treat IBS symptoms in women on a short-term basis. The safety and effectiveness of the Zelnorm has not yet been established in men. Studies of Zelnorm show it helps women whose primary IBS symptom is constipation. It works by increasing the movement of stool through the bowels. Use of Zelnorm also reduces bloating as well as pain and discomfort in the abdominal area.

Zelnorm works by mimicking the effects of the naturally occurring chemical called serotonin. Lotronex, in contrast, does essentially the opposite -- it inhibits the action of serotonin.

Over-the-counter medications may be useful, too, but be sure to check with your doctor first before taking them. The drug loperamide (Imodium A-D) may help relieve diarrhea. If you have constipation, you may be able to take over-the-counter laxatives once in a while. Ask your doctor which types, if any, will work for you and how often you can safely take them.

Reviewed by Charlotte E. Grayson, MD, March 2002.