Irritable Bowel Syndrome (IBS)

• What is irritable bowel syndrome (IBS)?
• What causes IBS?
• What are IBS symptoms?
• What are the complications of IBS?
• How is IBS diagnosed?
• How is IBS treated?
• Is there a relationship between IBS and small intestinal bacterial overgrowth?
• What is a reasonable approach to IBS?
• What is in the future for IBS?
• IBS At A Glance
• Patient Discussions: Irritable Bowel Syndrome - How Was Diagnosis Established

Featured irritable bowel syndrome (IBS) patient discussions on diagnosis experienced "I was diagnosed with irritable bowel syndrome in my early 20s. I am now 32. I had a colonoscopy performed, and my doctor told me to use Benefiber (a powder in my drinks), get plenty of exercise, and drink lots of water. Since then, I have gone to the emergency room because I looked very pregnant some evenings. I was just extremely constipated. I learned to deal with my instant pregnancies right before I started getting major pain in the right side of my stomach some evenings. I thought I had an erupting appendix! Back at the hospital, I learned to deal with that and the constant changes from diarrhea to constipation. " "I was diagnosed with IBS as a college student, 35 years ago. A barium enema test was used to rule out non-functional disease. The triggers back then remain the triggers today stress and alcohol. Bouts may last only a few days or go on for months. Yet there have been years where I have had no symptoms. The symptoms are mixed. Constipation always occurs with bloating. Diarrhea may be loose stools or very frequent stools. Pain is concentrated on the left side and lower back. Relief after a bowel movement is very brief. The pain returns very quickly and is then even more intense. I liken it to a hot poker up the rectum. I had a colonoscopy 4 years ago that was negative. Now I am about to get another as the doctor suspects diverticulosis. " "I was diagnosed with IBS when I was 17; I am now 32. I have also always suffered with anxiety, which I have found definitely has an effect on my IBS symptoms. It comes and goes, and I have been able to recognize certain triggers, for example, when my period is due, I have diarrhea and cramps. If I drink tea or coffee, I immediately have to use the bathroom, etc. My symptoms cycle through constipation and diarrhea alternately, and the pain is usually in my back or on one or other side of my abdomen, sometimes dull and nauseating, sometimes sharp. Heat pads help. At first I was given Colofac, but I don't use them now. I occasionally take peppermint oil capsules, but to be honest, I don't find anything does the job very well. I prefer to avoid known triggers if possible and deal with the symptoms. Exercise helps too; I walk a lot these days. IBS is very unpleasant but can be coped with. The longer you have it, the better you get to know yourself and your own symptoms and triggers, because everyone is different. " Read All Comments on Irritable Bowel Syndrome (IBS) » Top Searched Irritable Bowel Syndrome (IBS) Terms: ibs symptoms, ibs diet, ibs treatment, ibs medications, ibs causes, celiac disease, colitis, colon cancer, constipation, crohn's disease, diverticulitis, gerd, lactose intolerance Patient Discussions are not a substitute for professional medical advice, or treatment. See the disclaimer at the bottom of the comments page.

What is irritable bowel syndrome (IBS)?

Irritable bowel syndrome (IBS) is one of the most common ailments of the bowel (intestines) and affects an estimated 15% of persons in the US. The term, irritable bowel, is not a particularly accurate one since it implies that the bowel is responding irritably to normal stimuli, and this may or may not be the case. The several names for IBS, including spastic colon, spastic colitis, and mucous colitis, attest to the difficulty of getting a descriptive handle on the ailment. Moreover, each of the other names is itself as problematic as the term IBS.

IBS is best described as a functional disease. The concept of functional disease is particularly useful when discussing diseases of the gastrointestinal tract. The concept applies to the muscular organs of the gastrointestinal tract; the esophagus, stomach, small intestine, gallbladder, and colon. What is meant by the term, functional, is that either the muscles of the organs or the nerves that control the organs are not working normally, and, as a result, the organs do not function normally. The nerves that control the organs include not only the nerves that lie within the muscles of the organs but also the nerves of the spinal cord and brain to which they connect.

Some gastrointestinal diseases can be seen and diagnosed with the naked eye, such as ulcers of the stomach when visualized with certain methods. Thus, ulcers can be seen at surgery, on X-rays, and at endoscopy. Other diseases cannot be seen with the naked eye but can be seen and diagnosed with the microscope. For example, celiac disease and collagenous colitis are diagnosed by microscopic examination of biopsies of the small intestine and colon, respectively. In contrast, gastrointestinal functional diseases cannot be seen with the naked eye or with the microscope. In some instances, the abnormal function can be demonstrated by tests, for example, gastric emptying studies or antro-duodenal motility studies. However, these tests often are complex, are not widely available, and do not reliably detect the functional abnormalities. Accordingly, by default, functional gastrointestinal diseases are those involving the abnormal function of gastrointestinal organs in which abnormalities cannot be seen in the organs with either the naked eye or the microscope.

Occasionally, diseases that are thought to be functional are ultimately found to be associated with abnormalities that can be seen. Then, the disease moves out of the functional category. An example of this would be Helicobacter pylori infection of the stomach. Many patients with mild upper intestinal symptoms who were thought to have functional abnormal function of the stomach or intestines have been found to have an infection of the stomach with Helicobacter pylori. This infection can be diagnosed by seeing the bacterium and the inflammation (gastritis) it causes under the microscope . When the patients are treated with antibiotics, the Helicobacter pylori, gastritis, and symptoms disappear. Thus, recognition of Helicobacter pylori infection removed some patients' diseases from the functional category.

The distinction between functional disease and non-functional disease may, in fact, be blurry. Thus, even functional diseases probably have associated biochemical or molecular abnormalities that ultimately will be able to be measured. For example, functional diseases of the stomach and intestines may be shown ultimately to be caused by reduced levels of normal chemicals within the gastrointestinal organs, the spinal cord, or the brain. Should a disease that is demonstrated to be due to a reduced chemical still be considered a functional disease? I think not. In this theoretical situation, we can't see the abnormality with the naked eye or the microscope, but we can measure it. If we can measure an associated or causative abnormality, the disease probably should no longer be considered functional.

Despite the shortcomings of the term, functional, the concept of a functional abnormality is useful for approaching many of the symptoms originating from the muscular organs of the gastrointestinal tract. This concept applies particularly to those symptoms for which there are no associated abnormalities that can be seen with the naked eye or the microscope.

While IBS is a major functional disease, it is important to mention a second major functional disease referred to as dyspepsia, or functional dyspepsia. The symptoms of dyspepsia are thought to originate from the upper gastrointestinal tract; the esophagus, stomach, and the first part of the small intestine. The symptoms include upper abdominal discomfort, bloating (the subjective sense of abdominal fullness without objective distension), or objective distension (swelling, or enlargement). The symptoms may or may not be related to meals. There may be nausea with or without vomiting and early satiety (a sense of fullness after eating only a small amount of food).

The study of functional disorders of the gastrointestinal tract often is categorized by the organ of involvement. Thus, there are functional disorders of the esophagus, stomach, small intestine, colon, and gallbladder. The amount of research on functional disorders has been focused mostly on the esophagus and stomach (such as dyspepsia), perhaps because these organs are easiest to reach and study. Research into functional disorders affecting the small intestine and colon (for example, IBS) is more difficult to conduct and there is less agreement among the research studies. This probably is a reflection of the complexity of the activities of the small intestine and colon and the difficulty in studying these activities. Functional diseases of the gallbladder, like those of the small intestine and colon, also are more difficult to study.

Irritable Bowel Syndrome - How Was Diagnosis Established

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