IBS is a disorder that leads to abdominal pain and cramping, changes in bowel movements, and other symptoms. Many patients with IBS will complain of constipation or diarrhea or alternating between constipation and diarrhea.

Causes, incidence, and risk factors

It is not clear why patients develop IBS. Sometimes it occurs after an infection of the intestines. This is called postinfectious IBS. There may also be other triggers.

The intestine is connected to the brain. Signals go back and forth between the bowel and brain. These signals affect bowel function and symptoms. The nerves can become more active during stress, causing the intestines to be more sensitive and squeeze (contract) more.

IBS can occur at any age, but it often begins in the teen years or early adulthood. It is twice as common in women as in men.

About 1 in 6 people in the U.S. have symptoms of IBS. It is the most common intestinal problem that causes patients to be referred to a gastroenterologist.



Symptoms range from mild to severe. Most people have mild symptoms. Symptoms are different from person to person.

The main symptoms of IBS are abdominal pain, fullness, gas, and bloating that have been present for at least 3 days a month for the last 3 months. The pain and other symptoms will often:

·    Be reduced or go away after a bowel movement

·    Occur when there is a change in how often you have bowel movements

For some people, the symptoms may get worse for a few weeks or a month, and then decrease for a while. For other people, symptoms are present most of the time.

Signs and tests

Most of the time, your doctor can diagnose IBS based on your symptoms, with few or no tests. Eating a lactose-free diet for 2 weeks may help the doctor check for a possible lactase deficiency.

There is no test to diagnose IBS. Tests may be done to rule out other problems:

·    Blood tests to see if you have celiac disease or a low blood count (anemia)

·    Stool cultures to check for an infection

Some patients will have colonoscopy. You may need this test if:

·    Symptoms began later in life (over age 50)

·    You have symptoms such as weight loss or bloody stools

·    You have abnormal blood tests (such as a low blood count)

Other disorders that can cause similar symptoms include:

·    Celiac disease

·    Colon cancer (cancer rarely causes typical IBS symptoms, unless symptoms such as weight loss, blood in the stools, or abnormal blood tests are also present)

·    Crohn’s disease or ulcerative colitis

·    Small Intestinal Bacterial overgrowth (SIBO) – overgrowth of intestinal bacteria can lead to bloating, gas and change in bowels. Our doctors can perform breath testing to test for this diagnosis and prescribe antibiotics when appropriate.


The goal of treatment is to relieve symptoms.

Lifestyle changes can help in some cases of IBS. For example, regular exercise and improved sleep habits may reduce anxiety and help relieve bowel symptoms. Regular exercise has been shown to improve symptom frequency and severity.

Dietary changes can be helpful. However, no specific diet can be recommended for IBS, because the condition differs from one person to another. Nutrition consultation can be arranged when appropriate.

Medications our physicians might try include:

·    Anticholinergic medications (dicyclomine, belladonna, and hyoscyamine) taken about a half-hour before     eating to control intestine muscle spasms

·    Bisacodyl, Stool Softeners, Miralax to treat constipation

·    to treat constipation-predominant IBS, samples can be provided at our office

·    Loperamide to treat diarrhea

·    Low doses of tricyclic antidepressants (Elavil, Pamelor) to help relieve intestinal pain

·    Lubiprostone (Amitiza) for constipation symptoms

·    Rifaximin (Xifaxan), a non-absorbed antibiotic designed to treat intestinal bacteria without causing effects on the rest of the body. Rifaximin has been shown to improve certain IBS symptoms in recent randomized controlled trials and is an exciting new therapy our physicians have experience with.