Gas can also get trapped along the way, causing discomfort. Sometimes people with IBS pass mucus with their bowel movements. People with this disease also appear to be extra sensitive to distention of the colon. Studies using balloons to distend the colon have shown that patients with IBS experience pain and feel bloated at balloon pressures and volumes that are significantly lower than those that cause symptoms in people without the condition. Recent studies also have shown that neurotransmitters, chemicals that pass signals between nerves, are particularly active in the gastrointestinal tracts of people with the condition. One neurotransmitter in particular, serotonin, appears to be especially active in the blood and colon of people with IBS. These high levels of serotonin may stem in part from life stresses: The colon has many connections to the brain and central nervous system, which responds to stress and emotional upsets. And more than half of patients seen by a physician for IBS report stressful life events just before or at the same time as the onset of symptoms. Infection may also play a role in the causation of IBS. The theory is that infections of the intestinal lining prompt an immune-system response that makes the intestine hypersensitive. Some people who report IBS-like symptoms actually have mild celiac disease. People with celiac disease can’t digest gluten, a protein in wheat and other grains. When exposed to gluten, their immune systems damage the small intestine.
Irritable Bowel Syndrome
Chronic abdominal pain and constipation or diarrhea are hallmarks of IBS. Stephen Allen Christensen Irritable bowel syndrome (IBS) is defined as abdominal pain or discomfort and altered bowel habits in the absence of any other explanation for the symptoms. Ten to fifteen percent of the US population is affected to some degree, women are affected more often than men, and symptoms are more common in people between 30 and 50 years of age. (Mertz HR. Irritable bowel syndrome. N Engl J Med 2003;349: 2136-46) The cause of IBS is unknown. Underlying factors involved in the generation of symptoms include altered intestinal motility and increased sensitivity of the gut to various stimuli. Proposed Mechanisms (Causes) of Irritable Bowel Syndrome (IBS) Stress associated with increased levels of cortisol, slowed gastric emptying, and accelerated colonic transit Abnormal response to brain-intestine activation signals Altered colonic motility and abnormal neuronal function Heightened intestinal and colonic response to eating Abnormal gas propulsion and expulsion Subclinical inflammation with production of prostaglandins, bradykinins, 5-HTP, adenosine, and other factors that affect intestinal motility Intolerance to certain dietary substances, such as dairy or wheat Aberrant nocturnal housekeeper stripping wave of the small intestine, with subsequent small intestinal bacterial overgrowth (Talley NJ, Spiller R. Irritable bowel syndrome: a little understood organic bowel disease? Lancet 2002;360:555-64 and Pimentel M, et al. Lower frequency of MMC is found in IBS subjects with abnormal lactulose breath test, suggesting bacterial overgrowth. Dig Dis Sci 2002;47:2639-43) The symptoms of IBS may mimic those of other gastrointestinal conditions. Crohns disease, ulcerative colitis, celiac disease, thyroid dysfunction, or even cancer can be mistaken for IBS; usually, though, these diseases exhibit red flags (anemia, blood in the stool, fever, weight loss, or onset after 50 years of age) that lead physicians to an alternative diagnosis. Patients with IBS often consult a physician for abdominal pain, bloating, flatulence, and constipation or diarrhea.
Irritable Bowel Syndrome: a Primer
Since stress can bring on symptoms of IBS, stress management is an important way to deal with this condition. Exercise and some kind of relaxation training (such as meditation) are often recommended. Your doctor might also suggest talking with a counsellor to learn how to cope better. If you experience other symptoms such as anxiety, talk to your doctor on how to manage your condition. Medication for IBS is aimed at treating symptoms. Medications are available to slow down the movement of food through the digestive system and to control diarrhea. Laxatives are sometimes helpful for problem constipation, but people should not depend on them for regular bowel movements. Antidiarrhea medications (e.g., loperamide*) may be helpful for people who have mostly diarrhea as a symptom. Many other medications are available and your doctor can discuss them with you. Probiotics are bacteria that normally live in your intestines and found in certain foods, so they are considered “good” bacteria. Some studies suggest that IBS may be due to an imbalance or disruption of the normal “good” bacteria that’s present in the intestines. Probiotics may help the symptoms experienced by people with IBS by restoring this balance. However, further research into the use of probiotics in IBS needs to be done. *All medications have both common (generic) and brand names. The brand name is what a specific manufacturer calls the product (e.g., Tylenol).