Irritable Bowel Syndrome: What is It and How Do You Know if You Have It?

Irritable bowel syndrome (IBS) is the mostSerotonin, a chemical present in both the brain
common diagnosis (25-50%) given to peopleand the gut, has been suspected. An imbalance in
referred to stomach and intestine specialists. It isserotonin has been blamed for IBS. Serotonin
reported to affect between 10-15% of people inincreases the contractions of the intestine. Several
the U.S. However, it cannot be diagnosed by anymedications that either increase or decrease
specific tests. It is diagnosed by criteria. Theserotonin have been developed to treat
criteria are called the Rome II diagnostic criteriaconstipation or diarrhea predominant IBS.
because a group of doctors meet periodically toMore recently, research has been focusing on the
establish rules for labeling intestinal conditions thatcommon report of many people with IBS of a
have no diagnostic tests.distinct time that their IBS symptoms began,
These conditions are called syndromes becauseoften after some type of intestinal infection such
they don't meet the definition for a disease. Theyas food poisoning, traveler's diarrhea or
don't have a specific known cause and/orgastroenteritis. This "post-infectious" theory has
diagnostic test(s). They are often referred to aslead to theories of bowel injury and/or alterations
"functional" problems. The cause of the functionalin bacteria in the intestine. An imbalance of "good
problem in IBS is not known. By definition there isand bad" bacteria in the intestine is a theory.
no abnormality that can be seen on a biopsy,Some are treating people with antibiotics and/or
x-ray, blood or stool test. The diagnosis is madeprobiotics. Antibiotics kill bacteria. Probiotics are live
by applying criteria after exclusion of otherbacteria that are "good bacteria" like acidophilus
conditions or diseases of the intestine. There isand lactobacillus that can be taken as pill, capsule,
not a universally agreed upon consensus for whatpowder or eaten or drank in yogurt or milk.
constitutes an adequate evaluation to excludeFood intolerances have been proposed as a cause
other causes.of IBS by some, especially in Europe, but have
For IBS the criteria required to make thenot been accepted by most doctors in the U.S.
diagnosis is the presence of abdominal pain orTrials of elimination diets, with or without the use
discomfort that has been present for at least 3of food allergy or antibody tests have been
months in the past year (not necessarilyreported in a few studies or a lot of testimonials
consecutively) and has at least two out of threeto be helpful.
of the following features:Lactose intolerance is a common condition that
1. The pain or discomfort is relieved with a bowelcan cause symptoms that may be misdiagnosed
movement.as IBS and resolve with avoidance of lactose.
2. The beginning of pain or discomfort isUndiagnosed colitis or Crohn's disease can be a
associated with a change in frequency of bowelcause of symptoms that can be diagnosed by
movements.colonoscopy with biopsy of the intestine. Blood
3. The beginning of pain or discomfort istests for colitis and Crohn's disease also now
associated with a change in the appearance orexist.
consistency (hardness or softness) or stools.More recently, undiagnosed Celiac disease has
There are other symptoms that doctors use toemerged as a cause of what had been previously
support the diagnosis of IBS and to further dividebeen diagnosed as IBS in as many of 20% of
it into three different categories. The threepeople. Those with a diagnosis of IBS should be
categories are determined by whether there is ascreened for Celiac disease, as it is a common
predominant stool pattern of diarrhea orcondition, affecting 1 in 100 people. The
constipation or is the stool pattern alternatingsymptoms of abdominal pain, bloating, gas and
diarrhea and constipation. The supportingdiarrhea are common symptoms of Celiac disease
symptoms are as follows.and it is now known that untreated Celiacs can be
1. 3 bowel movements per day (diarrhea)constipated. Gluten free diet relieves these
3. Hard or lumpy stoolssymptoms in people who are gluten sensitive.
4. Loose, mushy or watery stoolsFurther information about irritable bowel
5. Straining during a bowel movementsyndrome, food intolerance, colitis, Crohn's
6. Urgency, or the sense that you need to rushdisease, lactose intolerance and Celiac disease
to the bathroom to have a bowel movementmay be found at
7. Feeling of incomplete emptying after a bowelIf you have symptoms suggestive of IBS or
movementhave been diagnosed as having IBS it is important
8. Passage of mucus or whitish material during athat you have an evaluation by a physician and
bowel movementother causes including colitis, Crohn's disease,
9. Feeling of abdominal fullness, bloating or swellinglactose intolerance, and Celiac disease are
Therefore, the diagnosis is made by a report ofexcluded. Food intolerance should also be
the symptoms and the doctor excluding otherconsidered. Minimum evaluation should include a
causes. The extent to which other conditions areblood count, stool tests for blood and pus cells,
excluded is highly variable and doctor dependent.screening lab tests for Celiac disease, colitis,
Self-diagnosis of IBS should be avoided becauseCrohn's and a colonoscopy. Talk to your doctor
serious conditions can cause symptoms thatabout the diagnosis and how other causes can be
mimic IBS.or have been excluded before accepting the
Theories of the cause of IBS are not proven.diagnosis of IBS.