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 diseases. 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 the tests results are negative, the doctor may diagnose IBS based on symptoms, including how often a patient may have had abdominal pain or discomfort during the past year, when the pain starts and stops in relation to bowel function, and how 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:

1. It is relieved by having a bowel movement.

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

3. 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.

What is the treatment for IBS?

Unfortunately, many people suffer from IBS for a long time before seeking medical treatment.

Up to 70 percent 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. A doctor will give the best treatments available for particular symptoms and encourage ways to manage stress and make changes to diet.

Medications can be an important part of relieving symptoms. A 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. Medications available specifically to treat IBS are:

? Alosetron hydrochloride (Lotronex), which 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.

? Tegaserod maleate (Zelnorm), which has been approved by the FDA for the short-term treatment of women with IBS whose primary symptom is constipation. Zelnorm is prescribed for a standard 4 to 6 weeks. If a person feels better and experiences a decrease in symptoms, the doctor may prescribe Zelnorm for an additional 4 to 6 weeks.

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. It's important to find a will need to work with to find the best combination of medicine, diet, counseling, and support to control the symptoms.

In general, these treatments are reserved for patients with moderate to severe symptoms, particularly if they experience psychological distress. Psychological treatments used to treat IBS include psychotherapy (dynamic and cognitive-behavioral therapy), relaxation therapy, hypnotherapy, and biofeedback therapy. Psychological treatments can also be combined.