Irritable Bowel Syndrome (IBS)
What is Irritable Bowel Syndrome (IBS)?
IBS is a common gastrointestinal disorder characterized by chronic abdominal pain and altered
bowel habits. It is found more often in women than men. Symptoms start before age 35 about
50 percent of the time.
What are the symptoms of IBS?
▪ Abdominal pain
▪ Constipation (hard to pass or infrequent bowel movements)
▪ Diarrhea (frequent, loose, watery stools)
▪ Sometimes alternating between constipation and diarrhea
What causes IBS?
One theory is that people with IBS have more sensitive intestines and react to things that may not
bother other people, such as stress, large meals, gas, medicines, certain foods, caffeine, or
A person who has IBS may not have normal movement in their GI tract. They may have spasms
at times. During a spasm, the muscles contract strongly, and the person may feel pain.
The colon is affected by the nervous systems which affects the flow of fluids into and out of the
colon. In IBS, when the contents in the colon move too quickly it absorbs less fluids which
results in diarrhea. Sometimes, the movement in the colon is too slow, which causes more fluid
to be absorbed. The result is constipation.
How is IBS diagnosed?
IBS is diagnosed by its symptoms and by the absence of other diseases which can cause similar
symptoms. The first step is to see your doctor for a complete physical. Your doctor will do a
health history. You may be asked questions about these symptoms which must be present to
make the diagnosis of IBS.
This includes the presence of abdominal pain. Abdominal pain should be present for at least 12
weeks out of the last 12 months.
It has two of these three features.
▪ It is relieved by a bowel movement.
▪ It is associated with 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 other symptoms must also be present.
▪ A change in the number of bowel movements and how often they happen.
▪ A change in how bowel movements look.
▪ Feeling a strong urge to have a bowel movement.
▪ Problems passing stool, such as straining or feeling that the bowel has not completely
▪ Mucus in the stool.
Bleeding, fever, weight loss, and persistent severe pain are not symptoms of IBS and may point
to other problems.
There is no one test for IBS but the tests listed below may be done to rule out other diseases.
This does not apply to all patients.
▪ Blood tests check for low red blood cell count, or high white blood cell count.
▪ Stool tests for bleeding, infection, virus, parasites, or inflammation.
▪ Colonoscopy or sigmoidoscopy checks the inside of the colon. A long flexible lighted
tube connected to a computer and TV monitor (endoscope) is inserted into the anus. The
doctor will be able to see any inflammation, bleeding, or ulcers on the colon wall.
During this exam the doctor may do a biopsy (take a sample of tissue from the lining of
the colon to view with a microscope).
What is the treatment?
No cure has been found for IBS, but there are many options to treat the symptoms. Most people
can control their symptoms with diet, stress management, and prescribed medicines. For some
people, however, IBS can be so disabling that they may be unable to work, attend social events,
or even travel short distances.
Medicines are an important part of easing symptoms.
ξ Fiber supplements or laxatives are sometimes used to treat constipation but must be used
with caution. Side effects can be bloating and gas.
ξ Loperamide or diphenoxylate with atropine Lomotil® are used to decrease diarrhea.
ξ Antispasmodics may help to control colon muscle spasms and reduce abdominal pain.
Tricyclic agents or small doses of antidepressant medicines may relieve some symptoms.
ξ Alosetron hydrochloride, (Lotronex®) is approved for women under age 55 with severe
IBS who have failed conventional treatment and whose main symptom is diarrhea. Its
use is restricted.
Each person with IBS is unique. 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. Fiber may lessen the IBS symptom of
constipation. It may not help with the symptoms of diarrhea or pain. Whole grains, fruits and
vegetables are good sources of fiber. High fiber diets may help prevent spasms. Some forms of
fiber keep water in the stool which helps keep stools soft. High fiber diets may cause gas and
bloating although some people report that these symptoms go away within a few weeks. A tip is
to increase fiber intake slowly by 2-3 grams per day. This may help reduce the risk of increased
gas and bloating.
Drinking 6-8 glasses of water a day is helpful especially if you have constipation. Beverages
with bubbles like soda may cause gas pain. Chewing gum and eating too quickly can cause you
to swallow air, which also leads to gas. Eating smaller meals more often may help IBS
symptoms. Large meals can cause cramping and diarrhea. Eating meals that are low in fat and
high in carbohydrates may help some patients and a low carbohydrate diet may help others.
Keeping a food record before changing your diet can help you be aware of the foods that cause
distress. Discuss your findings with your doctor. You may want to see a nutritionist who can
help you make changes to your diet.
How does stress affect IBS?
How to manage stress
What is stress? It is the “wear and tear” your body feels over time as it adjusts to feelings of
anxiety, tension, and anger. Stress can trigger intestinal spasms in people with IBS since the GI
tract has many nerves that connect it to the brain. Like the heart and lungs, the bowel is partly
controlled by the autonomic nervous system, which responds to stress. These nerves control the
way the bowel contracts and cause abdominal pain at stressful times. People often feel cramps
or ‘butterflies” when they are nervous or upset. In people with IBS, the bowel can be very
sensitive to even slight conflict or stress.
Learning to cope with stress is part of the treatment for IBS. Here is a list of some of the options
to manage stress. This list is to give you ideas that are a fit for you. Some of these options
require learning new skills.
▪ Getting enough sleep
▪ Counseling and support groups
▪ Hypnosis and cognitive behavioral therapy (offered at UWHC)
▪ Making lifestyle choices to decrease the stress you feel in your life
▪ Exercise such as walking or yoga
Is IBS linked to other diseases?
As its name states, it is a disorder which causes a great deal of discomfort and distress, but does
not harm the intestines, and does not lead to cancer. It is not related to Crohn’s disease or
For More Information
International Foundation for Functional Gastrointestinal Disorders
P.O. BOX 170864
Milwaukee, WI 53217
National Digestive Diseases Information Clearinghouse
2 Information Way
Bethesda, MD 20892-3570
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is not medical advice. This is not to be used for diagnosis or treatment of any medical condition. Because each
person’s health needs are different, you should talk with your doctor or others on your health care team when using
this information. If you have an emergency, please call 911. Copyright ©6/2015. University of Wisconsin Hospitals
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