Other symptoms are observed in association with irritable bowel syndrome, but are not necessarily a part of it. These symptoms include decreased appetite, back pain, chest pain, heartburn, acid indigestion, tiredness, weakness, feeling faint, and feeling agitated. Other symptoms are feeling a lump in the throat, feeling as if the throat was closing, feeling full after eating a small meal, nausea (with and without vomiting), and pain during sex.

ARE THE SIGNS AND SYMPTOMS OF IRRITABLE BOWEL SYNDROME THE SAME FOR EVERYONE?

No. The signs and symptoms of irritable bowel syndrome differ for each person.

WHAT CAUSES IRRITABLE BOWEL SYNDROME?

There does not seem to be a single cause of irritable bowel syndrome. Rather, this syndrome seems to be due to a combination of emotional, behavioral, and cognitive (thinking) factors in addition to factors related to how the body functions.

WHAT IS THE ROLE OF PSYCHOLOGICAL FACTORS IN IRRITABLE BOWEL SYNDROME?

A major component of irritable bowel syndrome is generally considered to be psychosomatic. Psychosomatic means that psychological causes, such as emotional distress, can influence physical functioning. Stress is known to affect the functioning of the digestive track in all people, especially those with irritable bowel syndrome. In irritable bowel syndrome the main stressor is considered to be anxiety. Major life stressors such as divorce, moving to a new city, the death of a loved lone, and physical/sexual abuse can also contribute to the development of this condition. Cognitive factors such as poor coping skills are also associated with irritable bowel syndrome.

Research has found that between 42% and 77% of patients with irritable bowel syndrome have psychiatric diagnoses, most of which are related to anxiety (such as panic disorder) or depression. Other common psychiatric diagnoses in people with irritable bowel syndrome are somatoform disorder (physical disorders due to psychological causes) and hypochondriasis (an excessive concern about one's physical health accompanied by emotional distress). By comparison, 20% of patients with other disorders of the digestive system have psychiatric diagnoses.

It is important to keep in mind that just because psychological stressors play a role in the development of signs or symptoms, this does not mean that those signs and symptoms are not real. Also, it is not fully understood whether psychological problems lead to irritable bowel syndrome or if irritable bowel syndrome leads to psychological problems. The answer may be that both are true to some extent.

There are no known physical causes of irritable bowel syndrome, such as a disease. The structure of the intestines is not abnormal and people with this condition do not tend to lose significant amounts of weight or have poor diets. However, some people report that the symptoms of irritable bowel syndrome begin shortly after recovering from an infection or surgery of the digestive system. Some people also develop signs and symptoms of irritable bowel syndrome after eating certain foods that they are sensitive too. It should be noted that there is no one food that causes irritable bowel syndrome or that makes the signs and symptoms worse.

WHAT IS THE ROLE OF VISCERAL HYPERALGESIA IN IRRITABLE BOWEL SYNDROME?

Visceral refers to viscera which are organs inside of the body, and typically refers to the organs inside of the belly. Hyperalgesia refers to extreme sensitivity to painful stimuli. Thus, visceral hyperalgesia is extreme sensitivity to painful stimuli in the internal organs, usually those of the belly. Visceral hyperalgesia can also mean an increased awareness of the normal movements of internal organs such as the intestines. When a small balloon is inflated in the intestine of patients with irritable bowel syndrome, they experience pain at lower levels of balloon inflation than patients without irritable bowel syndrome.

WHAT IS THE ROLE OF CHANGES IN THE MOVEMENT OF THE DIGESTIVE SYSTEM IN IBS?

Some scientists believe that one of the causes of irritable bowel syndrome is that the small and large intestine are overresponsive to stimulation and move abnormally. For example, one theory is that the colon (the major part of the large intestine) moves excessively when the body is stressed or the handling of fluids and electrolytes in the bowels are altered in some way. Electrolytes are chemical substances that are able to conduct electricity after they are melted or dissolved in water. However, alteration of fluid and electrolytes is only seen in a subset of patients with irritable bowel syndrome and are not related very well to bowel symptoms.

WHO IS GENERALLY AFFECTED BY IRRITABLE BOWEL SYNDROME?

Young adults (early to middle adulthood) are most affected by irritable bowel syndrome. Fifty percent of people with irritable bowel syndrome are below age 35. Women are twice as likely to have this syndrome than men. People of all races are affected, but Hispanics tend to be less affected than Caucasians and African Americans. Caucasians and African Americans tend to be affected at the same rate. Most people with this condition are otherwise healthy and have the condition for a long period of time before seeking medical help.

HOW COMMON IS IRRITABLE BOWEL SYNDROME?

Irritable bowel syndrome is the most common disorder of the intestine. In fact, between 20 and 50% of the patients seen by gastroenterologists (doctors that specialize in the study of the stomach and intestine) have this syndrome. Each year, between 2.5 and 3.5 million people visit a doctor to receive help with irritable syndrome. Between 25 and 55 million people are estimated to have this condition in the United States. In Western countries, between 6% and 22% of the population is affected with irritable bowel syndrome at a given time. The condition is also very common in Eastern countries such as Japan and China.

WHAT IS THE COURSE OF IRRITABLE BOWEL SYNDROME?

The course of this syndrome is highly variable and depends on the patient. For some people, the signs and symptoms occur only during a stressor and go away when the stressor goes away. For other people, the signs and symptoms seem to occur randomly and without warning and may never go away for good. For others, the signs and symptoms of irritable bowel syndrome will decrease or even disappear for periods of time and return at a later point. One study found that more than 50% of people with irritable bowel syndrome still experienced signs and symptoms 5 years after their initial diagnosis.

The pain in irritable bowel syndrome usually goes away when one poops or passes gas. For many people, this syndrome continues to occur throughout life. It can lead to hospitalizations, abdominal surgeries, and missing work three times more than people without bowel symptoms. However, irritable bowel syndrome is not life threatening and it is not linked to cancer.

HOW DOES IRRITABLE BOWEL SYNDROME AFFECT PEOPLE?

Whereas some people find the signs and symptoms of irritable bowel syndrome only slightly annoying, others find it to be moderate nuisance, and others are completely devastated by it.

HOW IS IRRITABLE BOWEL SYNDROME DIAGNOSED?

Irritable bowel syndrome is diagnosed by a doctor when the signs and symptoms mentioned above are reported together. However, other diagnoses must be eliminated as causing the problem, such as diseases that inflame the intestines, intolerance to lactose (a type of sugar present in many foods), or dysentery (an infectious disease causing severe, bloody diarrhea). To do this, patients may have their feces tested.

The colon (the major part of the large intestine) may be examined with a sigmoidoscopy, a procedure in which a scope is placed in the rear end and pushed up into the colon. A barium X-ray examination may also be done, which allows the doctor to see a picture of the intestines and other parts of the digestive tract. In addition to these procedures, it is essential for health care professionals to obtain a detailed history from the patient and to conduct a thorough physical examination.

WHAT ARE THE ROME CRITERIA?

The Rome criteria are a list of signs and symptoms that a team of experts agreed upon at a meeting in Rome, Italy that should be used to diagnose irritable bowel syndrome. Here they are:

At least three months of recurring pain or discomfort in the belly that is relieved by pooping, and/or is: 1) linked to a change in the rate at which one poops; or 2) linked to a change in the degree of firmness, thickness, or resistance to movement or separation of the substances that make up poop. In addition, 2 or more of the following symptoms must occur on 25% of the days or occasions: 1) changes in the rate in which one poops; 2) changes in the form of poop (for example, hard or watery poop); 3) changes in the way that poop passes through the body (for example, feeling an urgency to poop, a strain when pooping, or that the pooping was incomplete); 4) presence of mucus in the poop; and 5) feeling as if the belly is swollen.

HOW IS IRRITABLE BOWEL SYNDROME TREATED?

There is no known treatment of irritable bowel syndrome that works for everyone. Rather, different treatments work for different people. Staying away from foods that are known to make the signs and symptoms worse is almost always a good start. Many patients report benefiting from increasing the amount of dietary fiber (a substance in plants that cannot be digested by humans) eaten, because dietary fiber absorbs water that is in the poop, which makes it bigger. It is easier for bigger pieces of poop to move along the intestine and this helps relieve constipation. Some patients are recommended by their doctor to consume large amounts of dietary fiber and to increase the amount of exercise they do. Antidiarrhea drugs may be given briefly and are helpful in decreasing the amount of times that one has diarrhea.

Emotional support is also helpful, since the cause is psychological and the person is experiencing pain and discomfort. Thus, talking to a psychologist may prove helpful. Changing one's lifestyle so that significant stressors are avoided can prove helpful. Sometimes drugs are given to reduce anxiety and/or depression. The only way to know which treatment for irritable bowel syndrome works is through trial and error.

WHAT ELSE IS IRRITABLE BOWEL SYNDROME KNOWN AS?

Irritable bowel syndrome is also known as functional bowel syndrome, irritable colon, irritable colon syndrome, mucous colitis, nervous colon, and spastic colon. It is commonly abbreviated as IBS.

WHO DISCOVERED IRRITABLE BOWEL SYNDROME?

Sir William Osler, a Canadian medical doctor who lived in the U.S. and England was the first to describe this condition when he wrote about it in 1892. He named it mucous colitis.

ARE THERE ANY GOOD WEBSITES ON IRRITABLE BOWEL SYNDROME?

A great website that you can go to is The Irritable Bowel Syndrome Page. It has a large list of links to many websites that discuss this syndrome.