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Irritable Bowel Syndrome IBS

Irritable Bowel Syndrome (IBS)

Irritable bowel syndrome (IBS) is a condition that affects the gastrointestinal tract. It is important to note that IBS is very different from a similarly named disease, inflammatory bowel disease (IBD).

Recent research has shown that many symptoms of IBS are related to hyperactivity of the nerves.

See animation: Colonic motility, normal and the irritable bowel.

Irritable Bowel Syndrome (IBS) Symptoms

The main symptom of IBS is abdominal pain or discomfort associated with a change in your bowel habits. There are three subcategories of IBS, based on the types of symptoms you experience:

  • Mostly diarrhea and abdominal discomfort

  • Mostly constipation and abdominal discomfort

  • Alternating loose stools and constipation with abdominal discomfort

Other symptoms include:

  • Pain after a meal, during stress or during menses

  • Bloating

  • Mucous in stool

  • Urgency

  • Feeling of incomplete evacuation

  • Chest pain

  • Heartburn

  • Nausea

  • Difficulty swallowing or a feeling of a lump in the throat

You may experience symptoms unrelated to the intestine, including:

  • Headache

  • Sleep disturbances

  • Post-traumatic stress disorder

  • Temporomandibular joint disorder

  • Back pain

  • Pelvic pain

Some people are able to tolerate their symptoms very well and go about their regular routine. Other patients find that their symptoms prevent them from going to work or doing other activities. Often, stress is associated with the onset of symptoms; the symptoms then disappear when the stress is gone. Other patients may experience random IBS episodes and just as random remissions. Still others may have long periods of symptoms, followed by long symptom-free periods.

Symptoms and signs of Irritable Bowel Syndrome.
Symptoms and signs of Irritable Bowel Syndrome. (Click to Enlarge)

IBS Diagnosis at Johns Hopkins

A doctor often diagnoses IBS after ruling out other conditions. A trained and experienced gastroenterologist can recognize the classic symptoms of IBS and be able to exclude other diseases. Often, he or she can make an accurate diagnosis based on your symptoms, medical history and a physical examination. There are few laboratory tests or imaging tests that can help diagnose IBS.

International research groups have helped define the symptoms that allow for the diagnosis of IBS based on symptoms alone. Your doctor will use these criteria to aid in the diagnosis. Other diagnostic tools include:

Physical Exam and Blood Test

A diagnosis of IBS begins with a comprehensive physical exam during which you describe your symptoms and medical history. Your doctor will look for “red flags” that suggest the need for a more extensive evaluation. Red flags include:

  • Older than 50 years of age

  • Unexplained weight loss

  • Anemia (low iron)

  • Evidence of gastrointestinal bleeding

  • Persistent or progressive pain

  • Family history of colon cancer

  • Diarrhea that occurs when fasting, at night (nocturnal) or is of large volume

If you have symptoms of IBS and a red-flag symptom, you will probably need a more complete investigation. You may require further testing, such as a fecal occult blood test, which looks for hidden blood in the stool.


A colonoscopy should be performed if you are more than 50 years of age. If you have a family history of colon cancer, then regular colonoscopies should begin even earlier.

A colonoscopy is a procedure during which a long flexible tube is passed into the colon (or large bowel) while you sleep. This test allows the entire colon to be visualized.

During a colonoscopy:

  1. Your colon must be clear of stool so your doctor has good visibility. Preparations may include a liquid diet, enema and laxatives.

  2. You are given medications to make you comfortable and sleepy before the procedure.

  3. Your doctor inserts the colonoscope through the rectum and into the anus and large intestine or colon and checks to see if cancer or polyps are present.

  4. Biopsy forceps may be inserted through the scope in order to remove a small sample of tissue for further analysis.

  5. If there is a polyp, it can be removed it through the colonoscope.

  6. The procedure may cause some cramping or discomfort but is a very safe procedure.

IBS Treatment at Johns Hopkins

The goal of treatment for IBS is to provide relief from your symptoms. Your exact course of treatment will depend on the type and severity of your symptoms. Learn more about irritable bowel syndrome treatment at Johns Hopkins.

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