irritable bowel syndrome

Definition

Irritable bowel syndrome (IBS) is a common intestinal condition characterized by abdominal pain and cramps; changes in bowel movements (diarrhea, constipation, or both); gassiness; bloating; nausea; and other symptoms. There is no cure for IBS. Much about the condition remains unknown or poorly understood; however, dietary changes, drugs, and psychological treatment are often able to eliminate or substantially reduce its symptoms.

Description

IBS is the name people use today for a condition that was once called—among other things—colitis, mucous colitis, spastic colon, nervous colon, spastic bowel, and functional bowel disorder. Some of these names reflected the now-outdated belief that IBS is a purely psychological disorder, a product of the patient's imagination. Although modern medicine recognizes that stress can trigger IBS attacks, medical specialists agree that IBS is

a genuine physical disorder—or group of disorders— with specific identifiable characteristics.

No one knows for sure how many Americans suffer from IBS. Surveys indicate a range of 10-20%, with perhaps as many as 30% of Americans experiencing IBS at some point in their lives. IBS normally makes its first appearance during young adulthood, and in half of all cases symptoms begin before age 35. Women with IBS outnumber men by two to one, for reasons that are not yet understood. IBS is responsible for more time lost from work and school than any medical problem other than the common cold. It accounts for a substantial proportion of the patients seen by specialists in diseases of the digestive system (gastroenterologists). Yet only half—possibly as few as 15%—of IBS sufferers ever consult a doctor.

— Howard Baker

Abbreviation for International Biometric Society.

For more information on irritable bowel syndrome, visit Britannica.com.

Also known as spastic colon or mucous colitis. Abnormally increased motility of the large and small intestines, leading to pain and alternating diarrhoea and constipation; often precipitated by emotional stress.

A digestive disorder characterised by irregularities in the muscle contractions that normally propel waste through the large intestine to the rectum. This may result in diarrhoea or constipation, or alternating bouts of both. Other symptoms often include abdominal pain, flatulence, excess mucus, nausea, and heartburn. It is not certain what causes irritable bowel syndrome but anxiety, lack of fibre, high fat diets, and smoking tobacco may be contributing factors. Treatment usually involves reducing anxiety, making dietary adjustments (e.g. eating more fibre), and taking regular exercise to improve gut mobility. Sometimes a doctor may prescribe drugs that alleviate the pain and control the muscular contractions.

Definition

Irritable bowel syndrome (IBS) is a common intestinal condition characterized by abdominal pain and cramps; changes in bowel movements (diarrhea, constipation, or both); gassiness; bloating; nausea; and other symptoms. There is no recognized cure for IBS. Much about the condition remains unknown or poorly understood; however, dietary changes, drugs, and psychological treatment are often able to eliminate or substantially reduce its symptoms.

Description

IBS is the name people use today for a condition that was once called colitis, spastic colon, nervous colon, spastic bowel, and functional bowel disorder. Some of these names reflected the now-outdated belief that IBS is a purely psychological disorder and a product of the patient's imagination. Although modern medicine recognizes that stress can trigger IBS attacks, medical specialists agree that IBS is a genuine physical disorder or group of disorders with specific identifiable characteristics.

No one knows for sure how many Americans suffer from IBS. Surveys indicate a range of 10-20%, with perhaps as many as 30% of Americans experiencing IBS at some point in their lives. IBS normally makes its first appearance during young adulthood, and in half of all cases, symptoms begin before age 35. Women with IBS outnumber men by two to one, for reasons not yet understood. IBS is responsible for more time lost from work and school than any medical problem other than the common cold. It accounts for a substantial proportion of the patients seen by gastroenterologists, who are specialists in diseases of the digestive system. Yet only half—possibly as few as 15%—of IBS sufferers ever consult a doctor.

Causes & Symptoms

The symptoms of IBS tend to rise and fall in intensity rather than grow steadily worse over time. They always include intestinal (abdominal) pain that may be relieved by defecation; diarrhea or constipation; or diarrhea alternating with constipation. Other symptoms, which vary from person to person, include cramps, gassiness, bloating, nausea, a powerful and uncontrollable urge to defecate (urgency), passage of a sticky fluid (mucus) during bowel movements, or the feeling after finishing a bowel movement that the bowels are still not completely empty. The accepted diagnostic criteria, known as the Rome criteria, require at least three months of continuous or recurrent symptoms before IBS is diagnosed. According to Christine B. Dalton and Douglas A. Drossman in the American Family Physician, an estimated 70% of IBS cases can be described as "mild"; 25% as "moderate"; and 5% as "severe." In mild cases the symptoms are slight. As a general rule, they are not present all the time and do not interfere with work and other normal activities. Moderate IBS disrupts normal activities and may cause some psychological problems. People with severe IBS may constantly fear the unpredictable need for a bathroom. They often find living a normal life impossible and experience crippling psychological problems as a result. For some, the physical pain is constant and intense.

Causes

Researchers remain unsure about the cause or causes of IBS. It is called a functional disorder because it is thought to result from changes in the activity of the major part of the large intestine (the colon). After food is digested by the stomach and small intestine, the undigested material passes in liquid form into the colon, which absorbs water and salts. This process may take several days. In a healthy person the colon is quiet during most of that period except after meals, when its muscles contract in a series of wavelike movements called peristalsis. Peristalsis helps absorption by bringing the undigested material into contact with the colon wall. It also pushes undigested material that has been converted into solid or semisolid feces toward the rectum, where it remains until defecation. In IBS, however, the normal rhythm and intensity of peristalsis is disrupted. Sometimes there is too little peristalsis, which can slow the passage of undigested material through the colon and cause constipation. Sometimes there is too much, which has the opposite effect and causes diarrhea. A Johns Hopkins University study found that healthy volunteers experienced six to eight contractions of the colon each day, compared with up to 25 contractions a day for volunteers suffering from IBS with diarrhea, and an almost complete absence of contractions among constipated IBS volunteers. In addition to differences in the number of contractions, many of the IBS volunteers experienced powerful spasmodic contractions affecting a larger-than-normal area of the colon—"like having a Charlie horse in the gut," according to one of the investigators.

DIET. Some kinds of food and drink appear to play a key role in triggering IBS attacks. Food and drink that healthy people can ingest without any trouble may disrupt peristalsis in IBS patients, which probably explains why IBS attacks often occur shortly after meals. Chocolate, milk products, caffeine (in coffee, tea, colas, and other drinks), and large quantities of alcohol are some of the chief culprits. Other kinds of food have also been identified as problems, however, and the pattern of what can and cannot be tolerated is different for each person. Characteristically, IBS symptoms rarely occur at night and disrupt the patient's sleep.

In 2002 a research study reported that some children had trouble absorbing certain sugars from some fruit juices, particularly apple and pear juices. When children with IBS went off these juices for one month, 46% saw improvement in their IBS symptoms. Apple and pear juice contain more fructose than glucose sugar, which may be the cause of the poor absorption in IBS sufferers' intestines. Yet white grape juice, which contains almost equal portions of fructose and glucose, is more easily absorbed.

STRESS. Stress is an important factor in IBS because of the close nervous system connections between the brain and the intestines. Although researchers do not yet understand all of the links between changes in the nervous system and IBS, they point out the similarities between mild digestive upsets and IBS. Just as healthy people can feel nauseated or have an upset stomach when under stress, people with IBS react the same way, but to a greater degree. Finally, IBS symptoms sometimes intensify during menstruation, which suggests that female reproductive hormones are another trigger. In fact, a study published in 2002 confirmed that IBS symptoms worsened in women and that rectal sensitivity changed with the menstrual cycle in women with IBS. It also was the first study to contrast these changes with those in healthy women.

Diagnosis

Diagnosing IBS is a fairly complex task because the disorder does not produce changes that can be identified during a physical examination or by laboratory tests. When IBS is suspected, the doctor (a family doctor or a specialist) needs to determine whether the patient's symptoms satisfy the Rome criteria. The doctor rules out other conditions that resemble IBS, such as Crohn's disease and ulcerative colitis. These disorders are ruled out by taking a standard medical history, performing a physical examination, and ordering laboratory tests. The patient may be asked to provide a stool sample that can be tested for blood and intestinal parasites. In some cases x rays, bowel studies, or an internal examination of the colon using a flexible instrument inserted through the anus (a sigmoidoscope or colonoscope) is necessary.

Patients may also be asked to keep a diary of symptoms for two or three weeks, covering daily activities including meals and emotional responses to events. The doctor can then review the diary with the patient to identify possible problem areas.

Treatment

Dietary adjustments are critical to controlling IBS. For some patients, a high-fiber diet including whole grain breads and cereals, dried and fresh fruits, spinach, and oat bran can reduce digestive system irritation. For others, a high-fiber diet aggravates the symptoms. Many patients with IBS also find that avoiding alcohol, caffeine, sugar, and fatty, gas-producing, or spicy foods can prevent symptoms.

To control IBS symptoms that are triggered or made worse by stress, several stress management therapies may be helpful. These include yoga, meditation, hypnosis, biofeedback, exercise, muscle relaxation training, aromatherapy, hydrotherapy, and reflexology. Reflexology is a foot massage technique that focuses on manipulating different regions of the foot in order to bring harmony to specific organs and body systems. Hydrotherapy is the therapeutic use of water, as in a whirlpool bath.

Biofeedback, which teaches an individual to control muscle tension and any associated pain through thought and visualization techniques, is also a treatment option for IBS. In biofeedback treatments, sensors placed on the forehead of the patient are connected to a special machine that allows the patient and healthcare professional to monitor a visual and/or audible readout of the level of muscle tension and stress in the patient. Through relaxation and visualization exercises, the patient learns to relieve tension and can actually see or hear the results of his or her efforts instantly through a sensor readout on the biofeedback equipment. Once the technique is learned and the patient is able to recognize and differentiate between the feelings of muscle tension and muscle relaxation, the biofeedback equipment itself is no longer needed and the patient has a powerful, portable, and self-administered treatment tool to deal with pain and tension.

To soothe an irritated or inflamed digestive tract, an herbalist or holistic healthcare practitioner may recommend one or more herbs, including comfrey root (Symphytum officinale), hops (Humulus lupulus), Iceland moss (Cetraria islandica), Irish moss (Chondrus crispus), marsh mallow root (Althaea officinalis), oats (Avena sativa), quince seed (Cydonia oblonga), and slippery elm (Ulmus rubra).

Herbs that relieve gas associated with IBS (known as carminatives) include angelica (Angelica archangelica), aniseed (Pimpinella anisum), caraway (Carum carvi), cayenne (Capsicum annuum), German chamomile (Matricaria recutita), ginger (Zingiber officinale), thyme (Thymus vulgaris), and peppermint (Menthapiperata).

An infusion of meadowsweet (Filipendula ulmaria) may be helpful in treating diarrhea related to IBS, and herbs such as barberry (Berberis vulgaris), psyllium ovata seed, dandelion root (Taraxacum officinale), licorice (Glycyrrhiza glabra), and yellow dock (Rumex crispus) have laxative properties that can help to relieve constipation. More powerful laxative herbs, such as rhubarb root (Rheum palmatum), buckthorn (Rhamnus catharticus), and cascara (Rhamnus purshiana) should only be taken under the direction of a healthcare professional.

Individuals with cramp-like pains, or colic, can benefit from antispasmodic herbs such as German chamomile (Matricaria recutita), Valerian (Valeriana officinalis), lemon balm (Melissa officinalis), ginger (Zingiber officinale), and wild yam (Dioscorea villosa).

Homeopathy uses highly-diluted remedies that cause similar effects to the symptoms they are intended to treat in an effort to stimulate the body's natural immune response. A homeopathic physician might recommend a remedy of belladonna, colocynthis (bitter cucumber), phosphate of magnesia (Magnesia phosphorica), or wild hops (Bryonia alba) to relieve abdominal pain and cramping associated with IBS. As with all homeopathic remedies, the prescription depends on the individual's overall symptoms, mood, and temperament.

Acupuncture and guided imagery may be useful tools in treating IBS symptoms. Acupuncture involves the placement of thin needles into the skin at targeted locations on the body known as acupoints in order to harmonize the energy flow within the human body. An acupuncturist may also use moxibustion, which involves applying a heat source such as warm herbs to the acupoint, to treat IBS symptoms. Guided imagery techniques teach the patient to visualize a peaceful, soothing scene or situation to relax the body and better cope with the discomfort caused by IBS.

Allopathic Treatment

Dietary changes, sometimes supplemented by drugs or psychotherapy, are considered the key to successful treatment. A drug called alosetron (Lotronex) was approved by the Food and Drug Administration (FDA) in 2002 for limited marketing for treating women with diar-rhea-prominent IBS after some controversy in 2000 because of serious side effects from the drug. Its use should be limited to only those patients suffering from severe, chronic diarrhea-predominant IBS who have failed to respond to conventional therapy.

An individualized diet, low in saturated fats and foods that trigger the patient's reaction, can reduce symptoms for many IBS sufferers. Caffeine sources, sugar, and alcohol usually worsen symptoms. Bran or 15-25 grams a day of an over-the-counter psyllium laxative may also help both constipation and diarrhea. The patient can have milk or milk products if lactose intolerance is not a problem. Establishing set times for meals and bathroom visits may help people with irregular bowel habits, especially for constipated patients.

Although a high-fiber diet remains the standard treatment for constipated patients, such laxatives as lactulose or sorbitol may be prescribed. Loperamide and cholestyramine are suggested for diarrhea. Abdominal pain after meals can be reduced by taking antispasmodic drugs such as hyoscyamine or dicyclomine before eating.

Psychological counseling or behavioral therapy may be useful for some patients to reduce anxiety and to learn to cope with the pain and other symptoms of IBS. Relaxation therapy, hypnosis, biofeedback, and cognitive-behavioral therapy are examples of behavioral therapy.

When IBS produces constant pain that interferes with everyday life, antidepressant drugs can help by blocking pain transmission from the nervous system.

Expected Results

IBS is not a life-threatening condition. It does not cause intestinal bleeding or inflammation, nor does it cause other bowel diseases or cancer. Although IBS can last a lifetime, in up to 30% of cases the symptoms eventually disappear. Even if the symptoms cannot be eliminated, with appropriate treatment they can usually be decreased so that IBS becomes merely an occasional inconvenience. Treatment requires a long-term commitment, however; six months or more may be needed before the patient notices substantial improvement.

Resources

Books

Lynn, Richard B., and Lawrence S. Friedman. "Irritable Bowel Syndrome." In Harrison's Principles of Internal Medicine, edited by Anthony S. Fauci, et al. New York: McGraw-Hill, 1998.

Periodicals

"Can Fruit Juices Cause Irritable Bowel Syndrome?" Child Health Alert (June 2002):1.

Dalton, Christine B., and Douglas A. Drossman. "Diagnosis and Treatment of Irritable Bowel Syndrome." American Family Physician (February 1997): 875+.

Elliott, William T., and James Chan. "Alosetron Hydrochloride Tablets (Lotronex ™ GlaxoSmithKline) Reintroduction." Internal Medicine Alert (June 29, 2002): 94.

Houghton L.A. et al. "The Menstrual Cycle Affects Rectal Sensitivity in Patients with Irritable Bowel Syndrome but not Healthy Volunteers." Gut (April 2002): 471-474.

"Irritable Bowel Syndrome: Treating the Mind to Treat the Body." Tufts University Health & Nutrition Letter (September 1997): 4+.

Maxwell, P. R., M. A. Mendall, and D. Kumar. "Irritable Bowel Syndrome." The Lancet 350 (1997): 1691+.

Organizations

International Foundation for Functional Gastrointestinal Disorders. PO Box 17864, Milwaukee, WI 53217. (888) 964-2001. http://www.execpc.com/iffgd.

National Digestive Diseases Information Clearinghouse. 2 Information Way, Bethesda, MD 20892-3570. http://www.niddk.nih.gov/health/digest/nddic.htm.

[Article by: Paula Ford-Martin; Teresa G. Odle]

Definition

Irritable bowel syndrome (IBS) is a common gastrointestinal condition characterized by abdominal pain and cramps; changes in bowel movements (diarrhea, constipation, or both); gassiness; bloating; nausea; and other symptoms. There is no cure for IBS; however, dietary changes, stress management, and sometimes medications are often able to eliminate or substantially reduce its symptoms.

Description

IBS is the name people use today for a condition that was once called—among other things—spastic colitis, mucous colitis, spastic colon, nervous colon, spastic bowel, and functional bowel disorder. Some of these names reflected the now outdated belief that IBS is a purely psychological disorder, a product of the patient's imagination. Although modern medicine recognizes that stress, anxiety and depression can trigger IBS attacks, medical specialists agree that IBS is a genuine physical disorder—or group of disorders—with specific identifiable characteristics. IBS is considered a functional disorder because it is thought to result from changes in the activity of the major part of the large intestine (the colon).

Demographics

IBS is one of the most common functional gastrointestinal disorders, affecting 10-20 percent of adults in the United States. Research has demonstrated that symptoms compatible with IBS are about as common in school-age children as in adults. IBS normally makes its first appearance during young adulthood, and symptoms usually begin at about age 20. Women with IBS represent over 70 percent of IBS sufferers. IBS is responsible for more time lost from school and work than any medical problem—other than the common cold. It accounts for a substantial proportion of the patients seen by specialists in diseases of the digestive system (gastroenterologists).

A community-based study of 507 middle school and high school students by Hyams, et al, found that 6-14 percent of the adolescent population had IBS symptoms. Anxiety and depression scores were significantly higher for this group. Eight percent of all the students in the study had seen a physician for abdominal pain in the previous year.

Causes and Symptoms

Causes

Although the exact cause or causes of IBS are unknown, research suggests that people with IBS may have a colon that is more sensitive and reactive to certain foods and stress.

After food is digested by the stomach and small intestine, the undigested material passes in liquid form into the colon, which absorbs water, nutrients and salts. Normally, the colon is quiet during most of that period except after meals, when its muscles contract in a series of wavelike movements called peristalsis. Peristalsis helps absorption by bringing the undigested material into contact with the colon wall. It also pushes undigested material that has been converted into solid or semisolid feces toward the rectum, where it remains until a bowel movement occurs.

In IBS, however, the normal rhythm and intensity of peristalsis is disrupted. Sometimes there is too little peristalsis, which can slow the passage of undigested material through the colon and cause constipation. Sometimes there is too much, which has the opposite effect and causes diarrhea. In other cases, peristalsis can be spasmodic, causing sudden strong muscle contractions that come and go.

DIET. Some foods and beverages appear to play a key role in triggering IBS attacks. Certain foods and drinks may disrupt peristalsis in IBS patients, which may explain why IBS attacks often occur shortly after meals. Some of the chief culprits include:

• chocolate
• dairy products
• caffeine (in coffee, tea, colas, and other drinks)
• carbonated beverages (colas, pop, soda)
• wheat
• rye
• barley
• excess alcohol

Other foods also have been identified as problems, and the pattern of what can and cannot be tolerated is different for each person.

STRESS. Stress—feeling mentally or emotionally tense, troubled, angry or overwhelmed—stimulates colon spasms in people with IBS since there is a close nervous system connection between the brain and the intestines. A large network of nerves control the normal rhythmic contractions of the colon. Although researchers do not yet understand all of the links between changes in the nervous system and IBS, they point out the similarities between mild digestive upsets and IBS. Just as healthy people can feel nauseated or have an upset stomach when under stress, people with IBS react the same way, but to a greater degree.

MENSTRUATION. IBS symptoms sometimes intensify during menstruation, suggesting female reproductive hormones may trigger the condition.

Symptoms

The symptoms of IBS tend to rise and fall in intensity, rather than grow steadily worse over time. Symptoms always include:

• abdominal pain, which may be relieved by defecation
• diarrhea
• constipation
• diarrhea alternating with constipation

Other symptoms, which vary from person to person, include:

• cramps
• gassiness
• bloating
• nausea
• passage of mucus during bowel movements
• abnormal stool frequency—defined as greater than three bowel movements per day or less than three bowel movements per week
• abnormal stool form (lumpy, hard, loose, or watery stool)
• abnormal stool passage (straining, urgency, or feeling of incomplete bowel movement)

In general, symptoms are not present all the time and do not interfere with school and other normal activities. IBS symptoms rarely occur at night and disrupt the patient's sleep. Moderate IBS occasionally disrupts normal activities.

When to Call the Doctor

If a child has the following symptoms, the parent should contact the child's pediatrician or gastroenterologist:

• abdominal pain or diarrhea that wakes the child during the night
• persistent or severe abdominal pain
• unexplained weight loss
• rectal bleeding
• fever
• family history of irritable bowel disease

Diagnosis

The Rome II criteria are the accepted diagnostic criteria for IBS. These criteria were developed by an international group of pediatric gastroenterologists and include:

• Continuous or recurrent abdominal discomfort or pain for at least three months that is: a) Relieved with defecation and/or b) Associated with a change in frequency and/or c) Associated with a change in appearance of stool. Two or three of these features are present with an IBS diagnosis.
• No structural or metabolic abnormalities are present that may be responsible for the IBS symptoms.

The diagnosis of IBS is further supported by the presence of the symptoms listed previously. In addition, the primary pediatrician or gastroenterologist may confirm the diagnosis of IBS after questioning the child (if old enough to provide an accurate history of symptoms) or parent about his or her physical and mental health (the medical history), performing a physical examination, and ordering laboratory tests to rule out other conditions that resemble IBS, such as Crohn's disease and ulcerative colitis.

Diagnostic tests may include stool or blood tests, hydrogen breath test, or an x ray of the bowel, called a barium enema. When symptoms continue even after treatment, endoscopic tests such as a colonoscopy or sigmoidoscopy may be performed. An endoscopic test is an internal examination of the colon using a flexible instrument (a sigmoidoscope or colonoscope) that is inserted through the anus.

A nutritional assessment performed by a registered dietitian may be included in the child's diagnostic evaluation. The nutritional assessment includes a review of the child's fiber intake as well as his or her usual consumption of sugars such as sorbitol and fructose—common culprits of diarrhea.

Treatment

Dietary changes and sometimes medications are considered the keys to successful treatment. Psychosocial difficulties are also addressed and treated with therapy or counseling as needed. Treatment requires a long-term commitment; six months or more may be needed before the child notices substantial improvement.

Alternative Treatment

Alternative and complementary therapies include approaches that are considered to be outside the mainstream of traditional health care. Alternative and traditional approaches to IBS treatment overlap to a certain extent. Like traditional doctors, alternative practitioners advise a high-fiber diet to reduce digestive system irritation. They also suggest avoiding caffeine and fatty, gassy, or spicy foods, as well as alcohol. Recommended stress management techniques include yoga, meditation, guided imagery, hypnosis, biofeedback, and reflexology. Reflexology is a foot massage technique that is thought to relieve diarrhea, constipation, and other IBS symptoms.

The list of alternative treatments for IBS is quite long. It includes aromatherapy, homeopathy, hydrotherapy, juice therapy, acupuncture, chiropractic, osteopathy, naturopathic medicine, and Chinese traditional herbal medicine.

Before learning or practicing any particular technique, it is important for the parent/caregiver and child to learn about the therapy, its safety and effectiveness, potential side effects, and the expertise and qualifications of the practitioner. Although some practices are beneficial, others may be harmful to certain patients.

Relaxation techniques and dietary supplements should not be used as a substitute for medical therapies prescribed by a doctor. Parents should discuss these alternative treatments with the child's doctor to determine the techniques and remedies that may be beneficial for the child.

Nutritional Concerns

Dietary changes, including a low-fat, high-fiber diet, may help decrease IBS symptoms. The addition of wheat bran or other fiber may be suggested to decrease symptoms. The formula for determining the recommended fiber intake for children, as advised by the American Dietetic Association, is to take the child's age plus five to equal the grams of dietary fiber the child should consume daily. Fiber should be added gradually to the child's diet.

The doctor may recommend a lactose-free diet for two or three weeks to determine if lactose intolerance is causing the symptoms. Lactose is the milk sugar found in dairy products. Lactose intolerance is a common condition in up to 40% of patients with IBS. During the lactose-free period, the child should avoid all products containing lactose. The parent and child are asked to record the intake of all foods and beverages and note when symptoms occur after eating or drinking.

To identify other problem-causing foods or beverages, it is helpful for the parent and child to keep a diary of symptoms for two or three weeks, including daily activities, meals, symptoms and emotions. The doctor can then review the diary with the parent and child to identify possible problem areas.

In addition to lactose, known problem-causing substances include caffeine, beans, onions, cabbage, cucumbers, broccoli, fatty foods, alcohol, and certain medications. Once the specific substances that trigger symptoms are identified, they should be avoided. A registered dietitian can help the parent and child make specific dietary changes.

If lactose intolerance is a problem, the child may need to take calcium supplements or choose other foods high in calcium to meet the recommended daily requirement. If lactose intolerance is not a problem, the child can still have milk or milk products.

Medications

Medications affect each child differently, and no one medication works for every child with IBS. The child and parent will need to work with the doctor to find the best combination of medicine, diet, counseling and support to manage symptoms.

Stool softeners such as polyethelene glycol (Miralax) or an over-the-counter laxative may be recommended for constipation. Mineral oil also may be helpful. However, it is important not to use over-the-counter remedies without first consulting with the child's doctor.

Tricyclic antidepressants in low doses may be prescribed for pain relief. Antidepressants work by blocking pain transmission from the nervous system. Antispasmodic medications can slow bowel contractions and decrease diarrhea. Anticholinergics may help control intestinal cramping. Keep in mind that the effectiveness of these drugs to treat IBS has not been studied extensively in children.

Counseling and Support

Psychological counseling or behavioral therapy may be recommended for some patients to reduce anxiety and stress and to learn to cope with the symptoms of IBS. Biofeedback, guided imagery, relaxation therapy, hypnosis, and cognitive-behavioral therapy are examples of behavioral therapy. An ongoing and supportive doctor-patient relationship is also very important. The child and family must be reassured that although IBS causes symptoms that are uncomfortable and sometimes painful, it is not a harmful condition and does indicate a serious problem.

Prognosis

IBS is not a life-threatening condition. It is not an anatomical or structural defect, nor an identifiable physical or chemical disorder. IBS does not cause intestinal bleeding or inflammation, nor does it cause other gastrointestinal diseases or cancer. Although IBS can last a lifetime, in up to 30% of cases the symptoms eventually disappear. Even if the symptoms cannot be eliminated, with appropriate treatment they usually can be managed enough so IBS becomes merely an occasional inconvenience.

Prevention

Nutritional Concerns

To help prevent or decrease the child's symptoms, parents can:

• help the child identify and avoid problematic foods
• work with a registered dietitian to facilitate specific dietary changes
• incorporate changes in the child's diet gradually so his or her body has time to adjust
• establish set times for meals; not allowing the child to skip a meal
• encourage the child to drink at least eight 8-ounce glasses of water per day
• serve small portions during meals
• teach the child to eat slowly, to avoid swallowing too much air that can produce excess gas
• try offering smaller, more frequent meals
• keep a regular schedule for bathroom visits

Parental Concerns

Parents should reinforce with the child that IBS is not a life-threatening condition and that dietary changes and stress reduction can help reduce symptoms. Remind the child that six months or more may be needed before he or she notices substantial improvement in symptoms.

Resources

Books

Goldberg, Burton, John W. Anderson, and Larry Trivieri. Alternative Medicine: The Definitive Guide, 2nd Edition. Berkeley, CA: Ten Speed Press, 2002.

Lynn, Richard B., and Lawrence S. Friedman. "Irritable Bowel Syndrome." In Harrison's Principles of Internal Medicine, 16th Edition. Anthony S. Fauci, et al. New York: McGraw-Hill Professional, 2004.

Van Vorous, Heather. Eating for IBS Diet and Cookbook. New York, NY: Marlowe & Company, 2000.

Periodicals

Dalton, Christine B., and Douglas A. Drossman. "Diagnosis and Treatment of Irritable Bowel Syndrome." American Family Physician (Feb. 1997): 875+.

Hyams, J.S., et al. "Abdominal Pain and Irritable Syndrome in Adolescents: A Community-Based Study." Journal of Pediatrics (Aug. 1996): 220+.

Jarrett, Monica, et al. "Recurrent Abdominal Pain in Children: Forerunner to Adult Irritable Bowel Syndrome." Journal for Specialists in Pediatric Nursing (July-Sept. 2003): 81+.

Organizations

American College of Gastroenterology (ACG). P.O. Box 3099, Alexandria, VA 22302. (703) 820-7400. Web site: .

American Gastroenterological Association. 4930 Del Ray Ave., Bethesda, MD 20814. (301) 654-2055. Web site: .

International Foundation for Functional Gastrointestinal Disorders (IFFGD). P.O. Box 170864, Milwaukee, WI 53217-8076. (888) 964-2001. E-mail: iffgd@iffgd.org. Web site: .

Irritable Bowel Syndrome (IBS) Association. 1440 Whalley Ave., #145, New Haven, CT 06515. E-mail: ibsa@ibsassociation.org. Web site: .

Irritable Bowel Syndrome Self Help and Support Group. 1440 Whalley Ave., #145 New Haven, CT 06515. E-mail: ibs@ibsgroup.org. Web site: .

National Digestive Diseases Information Clearinghouse (NDDIC). 2 Information Way, Bethesda, MD 20892-3570. (800) 891-5389. E-mail: nddic@info.niddk.nih.gov. Web site: .

Web Sites

About IBS. Available online at

[Article by: Howard Baker]

This article is in need of attention from an expert on the subject. WikiProject Medicine or the Medicine Portal may be able to help recruit one. (January 2009)

Irritable bowel syndrome
Classification and external resources
ICD-10	K58.
ICD-9	564.1
DiseasesDB	30638
MedlinePlus	000246
eMedicine	med/1190
MeSH	D043183

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder. Also called spastic colon, it is a functional bowel disorder characterized by chronic abdominal pain, discomfort, bloating, and alteration of bowel habits in the absence of any detectable organic cause.^[1] In some cases, the symptoms are relieved by bowel movements.^[2] Diarrhea or constipation may predominate, or they may alternate (classified as IBS-D, IBS-C or IBS-A, respectively). IBS may begin after an infection (post-infectious, IBS-PI) or a stressful life event or may begin at onset of maturity without any other medical indicators.

Although there is no cure for IBS, there are treatments which attempt to relieve symptoms, including dietary adjustments, medication and psychological interventions. Patient education and a good doctor-patient relationship are also important.^[2]

Several conditions may present as IBS including celiac disease, mild infections, parasitic infections like giardiasis^[3], several inflammatory bowel diseases, functional chronic constipation, and chronic functional abdominal pain. In IBS, routine clinical tests yield no abnormalities, though the bowels may be more sensitive to certain stimuli, such as balloon insufflation testing. The exact cause of IBS is unknown. The most common theory is that IBS is a disorder of the interaction between the brain and the gastrointestinal tract, although there may also be abnormalities in the gut flora or the immune system.^[4][5]

IBS does not lead to more serious conditions in most patients.^{[6][7][8][9][10]} But it is a source of chronic pain, fatigue and other symptoms, and it increases a patient's medical costs,^[11][12] and contributes to work absenteeism.^[13][14] Researchers have reported that the high prevalence of IBS,^[15][16][17] in conjunction with increased costs produces a disease with a high societal cost.^[18] It is also regarded as a chronic illness and can dramatically affect the quality of a sufferer's life.

Contents 1 Classification 2 Symptoms 3 Diagnosis 3.1 Differential diagnosis 3.2 Misdiagnosis 4 Medical conditions that accompany IBS 5 Etiology 5.1 Psychosomatic illness 5.2 Immune reaction 5.3 Active infections 6 Treatment 6.1 Diet 6.2 Medication 6.2.1 Laxatives 6.2.2 Antispasmodics 6.2.3 Serotonin agonists 6.2.4 Serotonin antagonists 6.2.5 Other agents 6.3 Psychotherapy 6.4 Alternative treatments 7 Epidemiology 8 Economic cost of IBS 9 Research spending on IBS 10 History 11 See also 12 References 13 External links

Classification

IBS can be classified as either diarrhea-predominant (IBS-D), constipation-predominant (IBS-C) or IBS with alternating stool pattern (IBS-A or pain-predominant^[19]). In some individuals, IBS may have an acute onset and develop after an infectious illness characterized by two or more of the following: fever, vomiting, diarrhea, or positive stool culture. This post-infective syndrome has consequently been termed "post-infectious IBS" (IBS-PI).

Symptoms

The primary symptoms of IBS are abdominal pain or discomfort in association with frequent diarrhea or constipation, a change in bowel habits.^[20] There may also be urgency for bowel movements, a feeling of incomplete evacuation (tenesmus), bloating or abdominal distention.^[21] People with IBS more commonly than others have gastroesophageal reflux, symptoms relating to the genitourinary system, psychological symptoms, fibromyalgia, chronic fatigue syndrome, headache and backache.^[21][22]

A person with irritable bowel syndrome could also experience lethargy, first depression and disturbance when sleeping. Nausea is also experienced by some IBS sufferers, due to the motility of the intestine and bowel. Digestive disorder can develop at any age, but usually first experienced between ages 15 and 40.

Diagnosis

There is no specific laboratory or imaging test which can be performed to diagnose irritable bowel syndrome.^[23] Diagnosis of IBS involves excluding conditions which produce IBS-like symptoms, and then following a procedure to categorize the patient's symptoms.

Differential diagnosis

Because there are many causes of diarrhea that give IBS-like symptoms, the American Gastroenterological Association published a set of guidelines for tests to be performed to rule out other causes for these symptoms. These include gastrointestinal infections, lactose intolerance and Coeliac disease. Research has suggested that these guidelines are not always followed.^[23] Once other causes have been excluded, the diagnosis of IBS is performed using a diagnostic algorithm. Well-known algorithms include the Manning Criteria, the obsolete Rome I and II criteria, the Kruis Criteria, and studies have compared their reliability.^[24] The more recent Rome III Process was published in 2006. Physicians may choose to use one of these guidelines, or may simply choose to rely on their own anecdotal experience with past patients. The algorithm may include additional tests to guard against mis-diagnosis of other diseases as IBS. Such "red flag" symptoms may include weight loss, GI bleeding, anemia, or nocturnal symptoms. However, researchers have noted that red flag conditions may not always contribute to accuracy in diagnosis — for instance, as many as 31% of IBS patients have blood in their stool.^[24]

The diagnostic algorithm identifies a name which can be applied to the patient's condition based on the combination of the patient's symptoms of diarrhea, abdominal pain, and constipation. For example, the statement "50% of returning travelers had developed functional diarrhea while 25% had developed IBS" would mean that half the travelers had diarrhea while a quarter had diarrhea with abdominal pain. While some researchers believe this categorization system will help physicians understand IBS, others have questioned the value of the system and suggested that all IBS patients have the same underlying disease but with different symptoms.^[25]

Misdiagnosis

Published research has demonstrated that some poor patient outcomes are due to treatable causes of diarrhea being mis-diagnosed as IBS. Common examples include infectious diseases, coeliac disease,^[26] helicobacter pylori,^[27][28] parasites.^[5][29][30] See the list of causes of diarrhea for other conditions which can cause diarrhea.

Celiac disease in particular is often misdiagnosed as IBS. The American College of Gastroenterology recommends that all patients with symptoms of IBS be tested for coeliac disease.^[31] Chronic use of certain sedative-hypnotic drugs especially the benzodiazepines may cause irritable bowel like symptoms which can lead to a misdiagnosis of irritable bowel syndrome.^[32]

Medical conditions that accompany IBS

Researchers have identified several medical conditions, or comorbidities, which appear with greater frequency in patients diagnosed with IBS.

Headache, Fibromyalgia, Chronic fatigue syndrome and Depression: A study of 97,593 individuals with IBS identified comorbidities as headache, fibromyalgia, and depression.^[33] A systematic review found that IBS occurs in 51% of chronic fatigue syndrome patients and 49% of fibromyalgia patients, and psychiatric disorders were found to occur in 94% of IBS patients.^[22]

Inflammatory bowel disease (IBD): Some researchers have suggested that IBS is a type of low-grade inflammatory bowel disease.^[6] Researchers have suggested that IBS and IBD are interrelated diseases,^[7] noting that patients with IBD experience IBS-like symptoms when their IBD is in remission.^[8][9] A 3-year study found that patients diagnosed with IBS were 16.3 times more likely to develop IBD during the study period.^[10] Serum markers associated with inflammation have also been found in patients with IBS (see Causes).

Abdominal surgery: A recent (2008) study found that IBS patients are at increased risk of having unnecessary cholecystectomy (gall bladder removal surgery) not due to an increased risk of gallstones, but rather to abdominal pain, awareness of having gallstones, and inappropriate surgical indications.^[34] A 2005 study published in Digestive Disease Science reported that IBS patients are 87% more likely to undergo abdominal and pelvic surgery, and three times more likely to undergo gallbladder surgery.^[35] A study published in Gastroenterology came to similar conclusions, and also noted IBS patients were twice as likely to undergo hysterectomy.^[36]

Endometriosis: One study reported a statistically significant link between migraine headaches, IBS, and endometriosis.^[37]

Other chronic disorders: Interstitial cystitis may be associated with other chronic pain syndromes, such as irritable bowel syndrome and fibromyalgia. The connection between these syndromes is unknown.^[38]

Etiology

The cause of IBS is not known, but several hypotheses have been proposed. The risk of developing IBS increases sixfold after acute gastrointestinal infection. Post-infection, further risk factors are young age, prolonged fever, anxiety and depression.^[39]

Psychosomatic illness

Publications suggesting the role of brain-gut "axis" appeared in the 1990s, such as a study entitled Brain-gut response to stress and cholinergic stimulation in IBS published in the Journal of Clinical Gastroenterology in 1993.^[40] A 1997 study published in Gut magazine suggested that IBS was associated with a "derailing of the brain-gut axis."^[41] Psychological factors are still thought to be important in the etiology of IBS,^[22] and the symptoms defining the condition are referred to by some doctors as medically unexplained symptoms,^[42] a term some psychiatrists consider synonymous with somatoform disorder.

Immune reaction

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From the late 1990s, research publications began identifying specific biochemical changes present in tissue biopsies and serum samples from IBS patients. These studies identified cytokines and secretory products in tissues taken from IBS patients. The cytokines identified in IBS patients produce inflammation and are associated with the body's immune response.

Active infections

There is research to support IBS being caused by an as-yet undiscovered active infection. Most recently, a study found that the antibiotic Rifaximin provides sustained relief for IBS patients.^[43] While some researchers see this as evidence that IBS is related to an undiscovered agent, others believe IBS patients suffer from overgrowth of intestinal flora and the antibiotics are effective in reducing the overgrowth (known as small intestinal bacterial overgrowth).^[44] Other researchers have focused on an unrecognized protozoal infection as a cause of IBS^[5] as certain protozoal infections occur more frequently in IBS patients.^[45][46] Two of the protozoa investigated have a high prevalence in industrialized countries and infect the bowel, but little is known about them as they are recently emerged pathogens.

Blastocystis is a single-celled organism which has been reported to produce symptoms of abdominal pain, constipation and diarrhea in patients, along with headaches and depression,^[47] though these reports are contested by some physicians.^[48] Studies from research hospitals in various countries have identified high Blastocystis infection rates in IBS patients, with 38% being reported from London School of Hygiene & Tropical Medicine,^[49] 47% reported from the Department of Gastroenterology at Aga Khan University in Pakistan^[45] and 18.1% reported from the Institute of Diseases and Public Health at University of Ancona in Italy.^[46] Reports from all three groups indicate a Blastocystis prevalence of approximately 7% in non-IBS patients. Researchers have noted that clinical diagnostics fail to identify infection,^[50] and Blastocystis may not respond to treatment with common antiprotozoals.^{[51][52][53][54]}

Prevalence of protozoal infections in industrialized countries (United States and Canada) in 21st century.^[55][56]

Dientamoeba fragilis is a single-celled organism which produces abdominal pain and diarrhea. Studies have reported a high incidence of infection in developed countries, and symptoms of patients resolve following antibiotic treatment.^[55][57] One study reported on a large group of patients with IBS-like symptoms who were found to be infected with Dientamoeba fragilis, and experienced resolution of symptoms following treatment.^[58] Researchers have noted that methods used clinically may fail to detect some Dientamoeba fragilis infections.^[57] It is also found in people without IBS. ^[59]

Treatment

A questionnaire in 2006 designed to identify patients’ perceptions about IBS, their preferences on the type of information they need, as well as educational media and expectations from health care providers, revealed misperceptions about IBS developing into other conditions, including colitis, malnutrition, and cancer.^[60]

The survey found IBS patients were most interested in learning about foods to avoid (60%), causes of IBS (55%), medications (58%), coping strategies (56%), and psychological factors related to IBS (55%). The respondents indicated that they wanted their physicians to be available via phone or e-mail following a visit (80%), have the ability to listen (80%), and provide hope (73%) and support (63%).

Diet

Many different dietary modifications have been attempted to improve the symptoms of IBS. Some are effective in certain sub populations. As lactose intolerance and IBS have such similar symptoms a trial of a lactose free diet is often recommended.^[61] Fiber supplements have not been found to be effective in the general IBS population.^[62] They however might be beneficial in those who have a predominance of constipation.

Definitive determination of dietary issues can be accomplished by testing for the physiological effects of specific foods. The ELISA food allergy panel can identify specific foods to which a patient has a reaction. Other testing can determine if there are nutritional deficiencies secondary to diet that may also play a role. Removal of foods causing IgG immune response as measured using the ELISA food panel has been shown to substantially decrease symptoms of IBS in several studies.^[63]

There is no evidence that digestion of food or absorption of nutrients is problematic for those with IBS at rates different from those without IBS. However, the very act of eating or drinking can provoke an overreaction of the gastrocolic response in some patients with IBS due to their heightened visceral sensitivity, and this can lead to abdominal pain, diarrhea, and/or constipation.^[64]

Several of the most common dietary triggers are well-established by clinical studies at this point; research has shown that IBS patients are hypersensitive to fats and fructose.^[65][66]

It also appears that some foods are more difficult for the gut as evidenced by elevated food-specific IgG4 antibodies being present,^[67][68] while others increase colonic contractions, which may be painful, due to increased visceral sensitivity in IBS sufferers.^[69]

Fiber

In patients who have constipation predominant irritable bowel, soluble fiber at doses of 20 grams per day can reduce overall symptoms but will not reduce pain. The research supporting dietary fiber contains conflicting, small studies that are complicated by the heterogeneity of types of fiber and doses used.^[70] The one meta-analysis that controlled for solubility found that only soluble fiber improved global symptoms of irritable bowel and neither type of fiber reduced pain^[70] Positive studies have used 20-30 grams per day of psyllium seed.^[71][72] One study specifically examined the effect of dose and found that 20 grams of ispaghula husk was better than 10 grams and equivalent to 30 grams per day^[73] An uncontrolled study noted increased symptoms with insoluble fibers.^[74] It is unclear if these symptoms are truly increased compared with a control group. If the symptoms are increased, it is unclear if these patients were diarrhea predominant (which can be exacerbated by insoluble fiber^[75][76]), or if the increase is temporary before benefit occurs.

Medication

Medications may consist of stool softeners and laxatives in constipation-predominant IBS, and antidiarrheals (e.g., opiate, opioid or opioid analogs such as loperamide, codeine, diphenoxylate) in diarrhea-predominant IBS for mild symptoms.^[77][78][79]

Drugs affecting serotonin (5-HT) in the intestines can help reduce symptoms.^[80] Serotonin stimulates the gut motility and so agonists can help constipation-predominate irritable bowel, while antagonists can help diarrhea-predominant irritable bowel.

Laxatives

Main article: Laxative

For patients who do not adequately respond to dietary fiber, osmotic agents such as polyethylene glycol, sorbitol, and lactulose can help avoid 'cathartic colon' which has been associated with stimulant laxatives.^[81] Among the osmotic laxatives, 17 to 26 grams/day of polyethylene glycol (PEG) has been well studied.

• Lubiprostone (Amitiza), is a gastrointestinal agent used for the treatment of idiopathic chronic constipation and constipation-predominant IBS. It is well-tolerated in adults, including elderly patients. As of July 20, 2006, Lubiprostone had not been studied in pediatric patients. Lubiprostone is a bicyclic fatty acid (prostaglandin E1 derivative) which acts by specifically activating ClC-2 chloride channels on the apical aspect of gastrointestinal epithelial cells, producing a chloride-rich fluid secretion. These secretions soften the stool, increase motility, and promote spontaneous bowel movements (SBM). Unlike many laxative products, Lubiprostone does not show signs of tolerance, dependency, or altered serum electrolyte concentration.

Antispasmodics

Main article: Antispasmodic

The use of antispasmodic drugs (e.g. anticholinergics such as hyoscyamine or dicyclomine) may help patients, especially those with cramps or diarrhea. A meta-analysis by the Cochrane Collaboration concludes that if 6 patients are treated with antispasmodics, 1 patient will benefit.^[77] Antispasmodics can be divided in two groups: neurotropics and musculotropics. Neurotropics, such as atropine, act at the nerve fibre of the parasympathicus but also affect other nerves and have side effects. Musculotropics such as mebeverine act directly at the smooth muscle of the gastrointestinal tract, relieving spasm without affecting normal gut motility.^{[citation needed]} Since this action is not mediated by the autonomic nervous system, the usual anticholinergic side effects are absent.^{[citation needed]}

Serotonin agonists

• Tegaserod (Zelnorm), a selective 5-HT4 agonist for IBS-C, is available for relieving IBS constipation in women and chronic idiopathic constipation in men and women. On March 30, 2007, the Food and Drug Administration (FDA) requested that Novartis Pharmaceuticals voluntarily discontinue marketing of tegaserod based on the recently identified finding of an increased risk of serious cardiovascular adverse events (heart problems) associated with use of the drug. Novartis agreed to voluntarily suspend marketing of the drug in the United States and in many other countries. On July 27, 2007 the Food and Drug Administration (FDA) approved a limited treatment IND program for tegaserod in the USA to allow restricted access to the medication for patients in need if no comparable alternative drug or therapy is available to treat the disease. The USA FDA had issued two previous warnings about the serious consequences of Tegaserod. In 2005, tegaserod was rejected as an IBS medication by the European Union. Tegaserod, marketed as Zelnorm in the United States, was the only agent approved to treat the multiple symptoms of IBS (in women only), including constipation, abdominal pain and bloating. A meta-analysis by the Cochrane Collaboration concludes that if 17 patients are treated with typical doses of tegaserod, 1 patient will benefit.^[82]
• Selective serotonin reuptake inhibitor anti-depressants (SSRIs), because of their serotonergic effect, would seem to help IBS, especially patients who are constipation predominant. Initial crossover studies^[83] and randomized controlled trials^[84][85][86] support this role.

Serotonin antagonists

• Alosetron, a selective 5-HT3 antagonist for IBS-D, which is only available for women in the United States under a restricted access program, due to severe risks of side-effects if taken mistakenly by IBS-A or IBS-C sufferers.^{[citation needed]}
• Cilansetron, also a selective 5-HT3 antagonist, is undergoing further clinical studies in Europe for IBS-D sufferers. In 2005, Solvay Pharmaceuticals withdrew Cilansetron from the United States regulatory approval process after receiving a "not approvable" action letter from the FDA requesting additional clinical trials.^{[citation needed]}

Other agents

There is conflicting evidence about the benefit of antidepressants in IBS. Some meta-analysis have found a benefit while others have not.^[87] A meta-analysis of randomized controlled trials of mainly TCAs found 3 patients have to be treated with TCAs for one patient to improve.^[88] A separate randomized controlled trial found that TCAs are best for patients with diarrhea-predominant IBS.^[89]

Recent studies have suggested that rifaximin can be used as an effective treatment for abdominal bloating and flatulence,^[43][90] giving more credibility to the potential role of bacterial overgrowth in some patients with IBS.^[91]

The use of opioids is controversial due to the lack of evidence supporting their benefit and the potential risk of tolerance, physical dependence and addiction.^[92]

Psychotherapy

There is a strong brain-gut component to IBS. Cognitive behavioral therapy has been found to improve symptoms in a number of studies.^[93][94] Relaxation therapy has also been found to helpful.^[95]

Alternative treatments

Probiotics

A 2008 review found probiotics to be beneficial in the treatment of IBS.^[96] Many different type have be found to be effective including: Lactobacillus plantarum^[97] and Bifidobacteria infantis;^[98] however, one review found that only Bifidobacteria infantis showed efficacy.^[99] Some yoghurt is made using probiotics that may help ease symptoms of irritable bowel syndrome.^[100]

Iberogast

The multi-herbal extract Iberogast was found to be significantly superior to placebo via both an abdominal pain scale and an IBS symptom score after four weeks of treatment.^[101]

Peppermint oil

Enteric coated peppermint oil capsules has been advocated for IBS symptoms in adults and children;^[102] however, results from trials have been inconsistent.^[103][104] Peppermint oil may exacerbate the symptoms of Gastroesophageal_Reflux_Disease (GERD),^[105] and almost 4 in 5 IBS patients report GERD symptoms.^[106]

Acupuncture

Many sufferers of IBS seek relief using acupuncture.^{[citation needed]} A meta-analysis by the Cochrane Collaboration however concluded that most trials are of poor quality and that it is unknown whether acupuncture is more effective than placebo.^[107]

Epidemiology

Percentage of population with IBS reported in various studies in different countries

By Country: Studies have reported that the prevalence of IBS varies by country and by age range examined. The bar graph at right shows the percentage of the population reporting symptoms of IBS in studies from various geographic regions (see table below for references).

The following table contains a list of studies performed in different countries that measured the prevalence of IBS and IBS-like symptoms:

Percentage of Population Reporting Symptoms of IBS in Various Studies from Various Geographic Areas ** Check the Rome criteria studies (eg, at PubMed) and see how the reported prevalence rates drop! Also, one should be wary of trusting many of these study results - ref. 'Havidol'.
Country	Prevalence	Author/Year	Notes
Canada	6%[15]	Boivin,2001
Japan	10%[108]	Quigley,2006	Study measured prevalence of GI abdominal pain/cramping
United Kingdom	8.2%[109] 10.5%[16]	Ehlin,2003 Wilson,2004	Prevalence increased substantially 1970-2004
United States	14.1%[110]	Hungin, 2005	Most undiagnosed
United States	15%[15]	Boivin,2001	Estimate
Pakistan	14%[111]	Jafri, 2007	Much more common in 16-30 age range. Of IBS patients, 56% male, 44% female
Pakistan	34%[112]	Jafri,2005	College students
Mexico City	35%[17]	Schmulson, 2006	n=324. Also measured functional diarrhea and functional vomiting. High rates attributed to "stress of living in a populated city."
Brazil	43%[108]	Quigley,2006	Study measured prevalence of GI abdominal pain/cramping
Mexico	46%[108]	Quigley,2006	Study measured prevalence of GI abdominal pain/cramping

Returning Travelers: A study of United States residents returning from international travel found a high rate of IBS and persistent diarrhea which developed during travel and persisted upon return. The study examined 83 subjects in Utah, most of whom were returning missionaries. Of the 68 who completed the gastrointestinal questionnaire, 27 reported persistent diarrhea that developed while traveling, and 10 reported persistent IBS that developed while traveling.^[113]

Economic cost of IBS

The aggregate cost of irritable bowel syndrome in the United States has been estimated at $1.7-$10 billion in direct medical costs, with an additional $20 billion in indirect costs, for a total of $21.7-$30 billion.^[18] A study by a managed care company comparing medical costs of IBS patients to non-IBS controls identified a 49% annual increase in medical costs associated with a diagnosis of IBS.^[12] A 2007 study from a managed care oganization found that IBS patients incurred average annual direct costs of $5,049 and $406 in out-of-pocket expenses.^[11] A study of workers with IBS found that they reported a 34.6% loss in productivity, corresponding to 13.8 hours lost per 40 hour week.^[13] A study of employer-related health costs from a Fortune 100 company conducted with data from the 1990s found IBS patients incurred US $4527 in claims costs vs. $3276 for controls.^[114] A study on Medicaid costs conducted in 2003 by the University of Georgia's College of Pharmacy and Novartis found IBS was associated in an increase of $962 in Medicaid costs in California, and $2191 in North Carolina. IBS patients had higher costs for physician visits, outpatients visits, and prescription drugs. The study suggested the costs associated with IBS were comparable to those found in asthma patients.^[115]

Research spending on IBS

Further information: NIH funding of IBS Research

The National Institutes of Health provides a searchable database for grant awards since 1974 on its CRISP database, and provides dollar amounts for recent awards on its Intramural Grant Award Page. In 2006, the NIH awarded approximately 56 grants related to IBS, totalling approximately $18.7 million.

History

One of the first references to the concept of an "irritable bowel" appeared in the Rocky Mountain Medical Journal in 1950.^[116] The term was used to categorize patients who developed symptoms of diarrhea, abdominal pain, constipation, but where no well-recognized infective cause could be found. Early theories suggested that the Irritable Bowel was caused by a psychosomatic, or mental disorder.

See also

• Functional dyspepsia
• Chronic functional abdominal pain
• Functional constipation

References

1. ^ irritable bowel syndrome at Dorland's Medical Dictionary
2. ^ ^{a b} Mayer EA (April 2008). "Clinical practice. Irritable bowel syndrome". N. Engl. J. Med. 358 (16): 1692–9. doi:10.1056/NEJMcp0801447. PMID 18420501. 
3. ^ Intestinal Infection^{[dead link]}
4. ^ Yang CM, Li YQ (2007). "[The therapeutic effects of eliminating allergic foods according to food-specific IgG antibodies in irritable bowel syndrome]" (in Chinese). Zhonghua Nei Ke Za Zhi 46 (8): 641–3. PMID 17967233. 
5. ^ ^{a b c} Stark D, van Hal S, Marriott D, Ellis J, Harkness J (2007). "Irritable bowel syndrome: a review on the role of intestinal protozoa and the importance of their detection and diagnosis". Int. J. Parasitol. 37 (1): 11–20. doi:10.1016/j.ijpara.2006.09.009. PMID 17070814. 
6. ^ ^{a b} Bercik P, Verdu EF, Collins SM (2005). "Is irritable bowel syndrome a low-grade inflammatory bowel disease?". Gastroenterol. Clin. North Am. 34 (2): 235–45, vi-vii. doi:10.1016/j.gtc.2005.02.007. PMID 15862932. 
7. ^ ^{a b} Quigley EM (2005). "Irritable bowel syndrome and inflammatory bowel disease: interrelated diseases?". Chinese journal of digestive diseases 6 (3): 122–32. doi:10.1111/j.1443-9573.2005.00202.x. PMID 16045602. 
8. ^ ^{a b} Simrén M, Axelsson J, Gillberg R, Abrahamsson H, Svedlund J, Björnsson ES (2002). "Quality of life in inflammatory bowel disease in remission: the impact of IBS-like symptoms and associated psychological factors". Am. J. Gastroenterol. 97 (2): 389–96. doi:10.1111/j.1572-0241.2002.05475.x. PMID 11866278. 
9. ^ ^{a b} Minderhoud IM, Oldenburg B, Wismeijer JA, van Berge Henegouwen GP, Smout AJ (2004). "IBS-like symptoms in patients with inflammatory bowel disease in remission; relationships with quality of life and coping behavior". Dig. Dis. Sci. 49 (3): 469–74. doi:10.1023/B:DDAS.0000020506.84248.f9. PMID 15139501. 
10. ^ ^{a b} García Rodríguez LA, Ruigómez A, Wallander MA, Johansson S, Olbe L (2000). "Detection of colorectal tumor and inflammatory bowel disease during follow-up of patients with initial diagnosis of irritable bowel syndrome". Scand. J. Gastroenterol. 35 (3): 306–11. doi:10.1080/003655200750024191. PMID 10766326. 
11. ^ ^{a b} Nyrop KA, Palsson OS, Levy RL, Korff MV, Feld AD, Turner MJ, Whitehead WE (2007). "[www3.interscience.wiley.com/cgi-bin/fulltext/117987809/HTMLSTART Costs of health care for irritable bowel syndrome, chronic constipation, functional diarrhoea and functional abdominal pain]". Aliment Pharmacol Ther 26 (2): 237–48. doi:10.1111/j.1365-2036.2007.03370.x (inactive 2009-11-05). PMID 17593069. www3.interscience.wiley.com/cgi-bin/fulltext/117987809/HTMLSTART. 
12. ^ ^{a b} Levy RL, Von Korff M, Whitehead WE, Stang P, Saunders K, Jhingran P, Barghout V, Feld AD. (2001). "Costs of care for irritable bowel syndrome patients in a health maintenance organization". Am J Gastroenterol 96 (11): 3122–9. doi:10.1111/j.1572-0241.2001.05258.x. PMID 11721759. 
13. ^ ^{a b} Paré P, Gray J, Lam S, et al. (2006). "Health-related quality of life, work productivity, and health care resource utilization of subjects with irritable bowel syndrome: baseline results from LOGIC (Longitudinal Outcomes Study of Gastrointestinal Symptoms in Canada), a naturalistic study". Clinical therapeutics 28 (10): 1726–35; discussion 1710–1. doi:10.1016/j.clinthera.2006.10.010. PMID 17157129. 
14. ^ Maxion-Bergemann S, Thielecke F, Abel F, Bergemann R (2006). "Costs of irritable bowel syndrome in the UK and US". PharmacoEconomics 24 (1): 21–37. doi:10.2165/00019053-200624010-00002. PMID 16445300. 
15. ^ ^{a b c} Boivin M (October 2001). "Socioeconomic impact of irritable bowel syndrome in Canada". Can. J. Gastroenterol. 15 (Suppl B): 8B–11B. PMID 11694908. 
16. ^ ^{a b} Wilson S, Roberts L, Roalfe A, Bridge P, Singh S (July 2004). "Prevalence of irritable bowel syndrome: a community survey". Br J Gen Pract 54 (504): 495–502. PMID 15239910. 
17. ^ ^{a b} Schmulson M, Ortiz O, Santiago-Lomeli M, Gutierrez-Reyes G, Gutierrez-Ruiz MC, Robles-Diaz G, Morgan D (2006). "Frequency of functional bowel disorders among healthy volunteers in Mexico City" (PDF). Dig Dis. 24 (3-4): 342. doi:10.1159/000092887. PMID 16849861. http://content.karger.com/ProdukteDB/produkte.asp?Aktion=ShowPDF&ArtikelNr=92887&Ausgabe=231847&ProduktNr=224231&filename=92887.pdf. 
18. ^ ^{a b} Hulisz D (2004). "The burden of illness of irritable bowel syndrome: current challenges and hope for the future". J Manag Care Pharm. 10 (4): 299–309. PMID 15298528. 
19. ^ Holten KB, Wetherington A, Bankston L (2003). "Diagnosing the patient with abdominal pain and altered bowel habits: is it irritable bellyl syndrome?". Am Fam Physician 67 (10): 2157–62. PMID 12776965. http://www.aafp.org/afp/20030515/2157.html. 
20. ^ Schmulson MW, Chang L (1999). "Diagnostic approach to the patient with irritable bowel syndrome". Am. J. Med. 107 (5A): 20S–26S. doi:10.1016/S0002-9343(99)00278-8. PMID 10588169. 
21. ^ ^{a b} Talley NJ (2006). "Irritable bowel syndrome". Intern Med J 36 (11): 724–8. doi:10.1111/j.1445-5994.2006.01217.x. PMID 17040359. 
22. ^ ^{a b c} Whitehead WE, Palsson O, Jones KR (2002). "Systematic review of the comorbidity of irritable bowel syndrome with other disorders: what are the causes and implications?". Gastroenterology 122 (4): 1140–56. doi:10.1053/gast.2002.32392. PMID 11910364. 
23. ^ ^{a b} Yawn BP, Lydick E, Locke GR, Wollan PC, Bertram SL, Kurland MJ (2001). "Do published guidelines for evaluation of irritable bowel syndrome reflect practice?". BMC gastroenterology 1: 11. doi:10.1186/1471-230X-1-11. PMID 11701092. 
24. ^ ^{a b} Fass R, Longstreth GF, Pimentel M, et al. (2001). "Evidence- and consensus-based practice guidelines for the diagnosis of irritable bowel syndrome". Arch. Intern. Med. 161 (17): 2081–8. doi:10.1001/archinte.161.17.2081. PMID 11570936. 
25. ^ Talley NJ (2006). "A unifying hypothesis for the functional gastrointestinal disorders: really multiple diseases or one irritable gut?". Reviews in gastroenterological disorders 6 (2): 72–8. PMID 16699476. 
26. ^ Spiegel BM, DeRosa VP, Gralnek IM, Wang V, Dulai GS (2004). "Testing for celiac sprue in irritable bowel syndrome with predominant diarrhea: a cost-effectiveness analysis". Gastroenterology 126 (7): 1721–32. doi:10.1053/j.gastro.2004.03.012. PMID 15188167. 
27. ^ Su YC, Wang WM, Wang SY, et al. (August 2000). "The association between Helicobacter pylori infection and functional dyspepsia in patients with irritable bowel syndrome". Am. J. Gastroenterol. 95 (8): 1900–5. doi:10.1111/j.1572-0241.2000.02252.x. PMID 10950033. 
28. ^ Gerards C, Leodolter A, Glasbrenner B, Malfertheiner P (2001). "H. pylori infection and visceral hypersensitivity in patients with irritable bowel syndrome". Dig Dis 19 (2): 170–3. doi:10.1159/000050673. PMID 11549828. 
29. ^ Grazioli B, Matera G, Laratta C, et al. (March 2006). "Giardia lamblia infection in patients with irritable bowel syndrome and dyspepsia: a prospective study". World J. Gastroenterol. 12 (12): 1941–4. PMID 16610003. http://www.wjgnet.com/1007-9327/12/1941.asp. 
30. ^ Vernia P, Ricciardi MR, Frandina C, Bilotta T, Frieri G (1995). "Lactose malabsorption and irritable bowel syndrome. Effect of a long-term lactose-free diet". The Italian journal of gastroenterology 27 (3): 117–21. PMID 7548919. 
31. ^ American College of Gastroenterology Task Force on Irritable Bowel Syndrome (January 2009). "[www.nature.com/ajg/journal/v104/n1s/pdf/ajg2008122a.pdf An Evidence-Based Systematic Review on the Management of Irritable Bowel Syndrome]". pp. S1–S35. doi:10.1038/ajg.2008.122. www.nature.com/ajg/journal/v104/n1s/pdf/ajg2008122a.pdf. 
32. ^ Professor C Heather Ashton (1987). "Benzodiazepine Withdrawal: Outcome in 50 Patients". British Journal of Addiction 82: 655–671. http://www.benzo.org.uk/ashbzoc.htm. 
33. ^ Cole JA, Rothman KJ, Cabral HJ, Zhang Y, Farraye FA (2006). "Migraine, fibromyalgia, and depression among people with IBS: a prevalence study". BMC gastroenterology 6: 26. doi:10.1186/1471-230X-6-26. PMID 17007634. 
34. ^ Corazziari E, Attili AF, Angeletti C, De Santis A (2008). "Gallstones, cholecystectomy and irritable bowel syndrome (IBS) MICOL population-based study". Dig Liver Dis. 40 (12): 944–50. doi:10.1016/j.dld.2008.02.013. PMID 18406218. 
35. ^ Cole JA, Yeaw JM, Cutone JA, et al. (2005). "The incidence of abdominal and pelvic surgery among patients with irritable bowel syndrome". Dig. Dis. Sci. 50 (12): 2268–75. doi:10.1007/s10620-005-3047-1. PMID 16416174. 
36. ^ Longstreth GF, Yao JF (2004). "Irritable bowel syndrome and surgery: a multivariable analysis". Gastroenterology 126 (7): 1665–73. doi:10.1053/j.gastro.2004.02.020. PMID 15188159. 
37. ^ Tietjen GE, Bushnell CD, Herial NA, Utley C, White L, Hafeez F (2007). "Endometriosis is associated with prevalence of comorbid conditions in migraine". Headache 47 (7): 1069–78. doi:10.1111/j.1526-4610.2007.00784.x. PMID 17635599. 
38. ^ "Interstitial cystitis: Risk factors". Mayo Clinic. January 20, 2009. http://www.mayoclinic.com/health/interstitial-cystitis/DS00497/DSECTION=4. 
39. ^ Thabane M, Kottachchi DT, Marshall JK (2007). "[www3.interscience.wiley.com/cgi-bin/fulltext/117987841/HTMLSTART Systematic review and meta-analysis: The incidence and prognosis of post-infectious irritable bowel syndrome]". Aliment Pharmacol Ther 26 (4): 535–44. doi:10.1111/j.1365-2036.2007.03399.x (inactive 2009-11-05). PMID 17661757. www3.interscience.wiley.com/cgi-bin/fulltext/117987841/HTMLSTART. 
40. ^ Fukudo S, Nomura T, Muranaka M, Taguchi F (1993). "Brain-gut response to stress and cholinergic stimulation in irritable bowel syndrome. A preliminary study". J. Clin. Gastroenterol. 17 (2): 133–41. doi:10.1097/00004836-199309000-00009. PMID 8031340. 
41. ^ Orr WC, Crowell MD, Lin B, Harnish MJ, Chen JD (1997). "Sleep and gastric function in irritable bowel syndrome: derailing the brain-gut axis". Gut 41 (3): 390–3. PMID 9378397. 
42. ^ Deary, V.; Chalder, T.; Sharpe, M. (Oct 2007). "The cognitive behavioural model of medically unexplained symptoms: a theoretical and empirical review". Clinical psychology review 27 (7): 781–797. doi:10.1016/j.cpr.2007.07.002. ISSN 0272-7358. PMID 17822818.  edit
43. ^ ^{a b} Pimentel M, Park S, Mirocha J, Kane SV, Kong Y (2006). "The effect of a nonabsorbed oral antibiotic (rifaximin) on the symptoms of the irritable bowel syndrome: a randomized trial". Ann. Intern. Med. 145 (8): 557–63. PMID 17043337. 
44. ^ Posserud I, Stotzer PO, Björnsson ES, Abrahamsson H, Simrén M (2007). "Small intestinal bacterial overgrowth in patients with irritable bowel syndrome". Gut 56 (6): 802–8. doi:10.1136/gut.2006.108712. PMID 17148502. 
45. ^ ^{a b} Yakoob J, Jafri W, Jafri N, et al. (2004). "Irritable bowel syndrome: in search of an etiology: role of Blastocystis hominis". Am. J. Trop. Med. Hyg. 70 (4): 383–5. PMID 15100450. 
46. ^ ^{a b} Giacometti A, Cirioni O, Fiorentini A, Fortuna M, Scalise G (1999). "Irritable bowel syndrome in patients with Blastocystis hominis infection". Eur. J. Clin. Microbiol. Infect. Dis. 18 (6): 436–9. doi:10.1007/s100960050314. PMID 10442423. 
47. ^ Qadri SM, al-Okaili GA, al-Dayel F (1989). "Clinical significance of Blastocystis hominis". J. Clin. Microbiol. 27 (11): 2407–9. PMID 2808664. 
48. ^ Markell EK, Udkow MP (1986). "Blastocystis hominis: pathogen or fellow traveler?". Am. J. Trop. Med. Hyg. 35 (5): 1023–6. PMID 3766850. 
49. ^ Windsor J (2007). "B. hominis and D. fragilis: Neglected human protozoa". British Biomedical Scientist: 524–7. http://www.ibms.org/index.cfm?method=publications.biomedical_scientist&subpage=contents_2007_July. ^{[dead link]}
50. ^ Stensvold R, Brillowska-Dabrowska A, Nielsen HV, Arendrup MC (2006). "Detection of Blastocystis hominis in unpreserved stool specimens by using polymerase chain reaction". J. Parasitol. 92 (5): 1081–7. doi:10.1645/GE-840R.1. PMID 17152954. 
51. ^ Yakoob J, Jafri W, Jafri N, Islam M, Asim Beg M (2004). "In vitro susceptibility of Blastocystis hominis isolated from patients with irritable bowel syndrome". Br. J. Biomed. Sci. 61 (2): 75–7. PMID 15250669. 
52. ^ Haresh K, Suresh K, Khairul Anus A, Saminathan S (1999). "Isolate resistance of Blastocystis hominis to metronidazole". Trop. Med. Int. Health 4 (4): 274–7. doi:10.1046/j.1365-3156.1999.00398.x. PMID 10357863. 
53. ^ Markell EK, Udkow MP (1986). "Blastocystis hominis: pathogen or fellow traveler?". Am. J. Trop. Med. Hyg. 35 (5): 1023–6. PMID 3766850. 
54. ^ Ok UZ, Girginkardeşler N, Balcioğlu C, Ertan P, Pirildar T, Kilimcioğlu AA (1999). "Effect of trimethoprim-sulfamethaxazole in Blastocystis hominis infection". Am. J. Gastroenterol. 94 (11): 3245–7. doi:10.1111/j.1572-0241.1999.01529.x. PMID 10566723. 
55. ^ ^{a b} Lagacé-Wiens PR, VanCaeseele PG, Koschik C (2006). "Dientamoeba fragilis: an emerging role in intestinal disease". CMAJ : Canadian Medical Association journal = Journal De l'Association Medicale Canadienne 175 (5): 468–9. doi:10.1503/cmaj.060265. PMID 16940260. 
56. ^ Amin OM (2002). "Seasonal prevalence of intestinal parasites in the United States during 2000". Am. J. Trop. Med. Hyg. 66 (6): 799–803. PMID 12224595. 
57. ^ ^{a b} Stensvold CR, Arendrup MC, Mølbak K, Nielsen HV (2007). "The prevalence of Dientamoeba fragilis in patients with suspected enteroparasitic disease in a metropolitan area in Denmark". Clin. Microbiol. Infect. 13 (8): 839–42. doi:10.1111/j.1469-0691.2007.01760.x. PMID 17610603. 
58. ^ Borody T, Warren E, Wettstein A, et al. (2002). "Eradication of Dientamoeba fragilis can resolve IBS-like symptoms". J Gastroenterol Hepatol 17 (Suppl; pages=A103). 
59. ^ Windsor JJ, Macfarlane L (May 2005). "Irritable bowel syndrome: the need to exclude Dientamoeba fragilis". Am. J. Trop. Med. Hyg. 72 (5): 501; author reply 501–2. PMID 15891119. http://www.ajtmh.org/cgi/content/full/72/5/501. Retrieved 2009-11-04. 
60. ^ Halpert AD, Thomas AC, Hu Y, Morris CB, Bangdiwala SI, Drossman DA (2006). "A survey on patient educational needs in irritable bowel syndrome and attitudes toward participation in clinical research". J Clin Gastroenterol 40 (1): 37–43. doi:10.1097/01.mcg.0000190759.95862.08. PMID 16340632. 
61. ^ Böhmer CJ, Tuynman HA (August 2001). "The effect of a lactose-restricted diet in patients with a positive lactose tolerance test, earlier diagnosed as irritable bowel syndrome: a 5-year follow-up study". Eur J Gastroenterol Hepatol 13 (8): 941–4. doi:10.1097/00042737-200108000-00011. PMID 11507359. 
62. ^ Brandt LJ, Bjorkman D, Fennerty MB, et al. (November 2002). "Systematic review on the management of irritable bowel syndrome in North America". Am. J. Gastroenterol. 97 (11 Suppl): S7–26. doi:10.1016/S0002-9270(02)05657-5. PMID 12425586. 
63. ^ Atkinson W, Sheldon TA, Shaath N, Whorwell PJ (2004). "Food elimination based on IgG antibodies in irritable bowel syndrome: a randomised controlled trial". Gut 53 (10): 1459–64. doi:10.1136/gut.2003.037697. PMID 15361495. 
64. ^ Sjölund K, Ekman R, Lindgren S, Rehfeld J (1996). "Disturbed motilin and cholecystokinin release in the irritable bowel syndrome". Scand J Gastroenterol 31 (11): 1110–4. doi:10.3109/00365529609036895. PMID 8938905. 
65. ^ Caldarella MP, Milano A, Laterza F, Sacco F, Balatsinou C, Lapenna D, Pierdomenico SD, Cuccurullo F, Neri M (2005). "Visceral sensitivity and symptoms in patients with constipation- or diarrhea-predominant irritable bowel syndrome (IBS): effect of a low-fat intraduodenal infusion". Am J Gastroenterol 100 (2): 383–9. doi:10.1111/j.1572-0241.2005.40100.x. PMID 15667496. 
66. ^ Choi, Y. Fats, Fructose May Contribute to IBS Symptoms. ACG 68th Annual Scientific Meeting: Abstract 21, presented October 13, 2003; Abstract 547, presented October 14, 2003.
67. ^ Zar S, Benson MJ, Kumar D (2005). "Food-specific serum IgG4 and IgE titers to common food antigens in irritable bowel syndrome". Am J Gastroenterol 100 (7): 1550–7. doi:10.1111/j.1572-0241.2005.41348.x. PMID 15984980. 
68. ^ Zar S, Mincher L, Benson MJ, Kumar D (2005). "Food-specific IgG4 antibody-guided exclusion diet improves symptoms and rectal compliance in irritable bowel syndrome". Scand J Gastroenterol 40 (7): 800–7. doi:10.1080/00365520510015593. PMID 16109655. 
69. ^ Mayer EA, Berman S, Suyenobu B, Labus J, Mandelkern MA, Naliboff BD, Chang L (2005). "Differences in brain responses to visceral pain between patients with irritable bowel syndrome and ulcerative colitis". Pain 115 (3): 398–409. doi:10.1016/j.pain.2005.03.023. PMID 15911167. 
70. ^ ^{a b} Bijkerk C, Muris J, Knottnerus J, Hoes A, de Wit N (2004). "Systematic review: the role of different types of fiber in the treatment of irritable bowel syndrome". Aliment Pharmacol Ther 19 (3): 245–51. doi:10.1111/j.0269-2813.2004.01862.x. PMID 14984370. 
71. ^ Prior A, Whorwell P (1987). "Double blind study of ispaghula in irritable bowel syndrome". Gut 28 (11): 1510–3. doi:10.1136/gut.28.11.1510. PMID 3322956. 
72. ^ Jalihal A, Kurian G (1990). "Ispaghula therapy in irritable bowel syndrome: improvement in overall well-being is related to reduction in bowel dissatisfaction". J Gastroenterol Hepatol 5 (5): 507–13. doi:10.1111/j.1440-1746.1990.tb01432.x. PMID 2129822. 
73. ^ Kumar A, Kumar N, Vij J, Sarin S, Anand B (1987). "Optimum dosage of ispaghula husk in patients with irritable bowel syndrome: correlation of symptom relief with whole gut transit time and stool weight". Gut 28 (2): 150–5. doi:10.1136/gut.28.2.150. PMID 3030900. 
74. ^ Francis CY, Whorwell PJ (1994). "Bran and irritable bowel syndrome: time for reappraisal". Lancet 344 (8914): 39–40. doi:10.1016/S0140-6736(94)91055-3. PMID 7912305. 
75. ^ Cann P, Read N, Holdsworth C, Barends D (1984). "Role of loperamide and placebo in management of irritable bowel syndrome (IBS)". Dig Dis Sci 29 (3): 239–47. doi:10.1007/BF01296258. PMID 6365490. 
76. ^ Cann P, Read N, Holdsworth C (1984). "What is the benefit of coarse wheat bran in patients with irritable bowel syndrome?". Gut 25 (2): 168–73. doi:10.1136/gut.25.2.168. PMID 6319244. 
77. ^ ^{a b} Quartero A, Meineche-Schmidt V, Muris J, Rubin G, de Wit N (2005). "Bulking agents, antispasmodic and antidepressant medication for the treatment of irritable bowel syndrome". Cochrane Database Syst Rev (2): CD003460. doi:10.1002/14651858.CD003460.pub2. PMID 15846668. 
78. ^ Lesbros-Pantoflickova D, Michetti P, Fried M, Beglinger C, Blum A (2004). "Meta-analysis: The treatment of irritable bowel syndrome". Aliment Pharmacol Ther 20 (11-12): 1253–69. doi:10.1111/j.1365-2036.2004.02267.x. PMID 15606387. 
79. ^ Jailwala J, Imperiale T, Kroenke K (2000). "Pharmacologic treatment of the irritable bowel syndrome: a systematic review of randomized, controlled trials". Ann Intern Med 133 (2): 136–47. PMID 10896640. 
80. ^ Talley N (2001). "Serotoninergic neuroenteric modulators". Lancet 358 (9298): 2061–8. doi:10.1016/S0140-6736(01)07103-3. PMID 11755632. 
81. ^ Joo J, Ehrenpreis E, Gonzalez L, Kaye M, Breno S, Wexner S, Zaitman D, Secrest K (1998). "Alterations in colonic anatomy induced by chronic stimulant laxatives: the cathartic colon revisited". J Clin Gastroenterol 26 (4): 283–6. doi:10.1097/00004836-199806000-00014. PMID 9649012. 
82. ^ Evans B, Clark W, Moore D, Whorwell P (2004). "Tegaserod for the treatment of irritable bowel syndrome". Cochrane Database Syst Rev (1): CD003960. doi:10.1002/14651858.CD003960.pub2. PMID 14974049. 
83. ^ Tack J, Broekaert D, Fischler B, Oudenhove L, Gevers A, Janssens J (2006). "A controlled crossover study of the selective serotonin reuptake inhibitor citalopram in irritable bowel syndrome". Gut 55 (8): 1095–103. doi:10.1136/gut.2005.077503. PMID 16401691. 
84. ^ Vahedi H, Merat S, Rashidioon A, Ghoddoosi A, Malekzadeh R (2005). "The effect of fluoxetine in patients with pain and constipation-predominant irritable bowel syndrome: a double-blind randomized-controlled study". Aliment Pharmacol Ther 22 (5): 381–5. doi:10.1111/j.1365-2036.2005.02566.x. PMID 16128675. 
85. ^ Creed F, Fernandes L, Guthrie E, Palmer S, Ratcliffe J, Read N, Rigby C, Thompson D, Tomenson B (2003). "The cost-effectiveness of psychotherapy and paroxetine for severe irritable bowel syndrome". Gastroenterology 124 (2): 303–17. doi:10.1053/gast.2003.50055. PMID 12557136. 
86. ^ Tabas G, Beaves M, Wang J, Friday P, Mardini H, Arnold G (2004). "Paroxetine to treat irritable bowel syndrome not responding to high-fiber diet: a double-blind, placebo-controlled trial". Am J Gastroenterol 99 (5): 914–20. doi:10.1111/j.1572-0241.2004.04127.x. PMID 15128360. 
87. ^ "UpToDate Inc." (subscription required). http://www.uptodate.com/online/content/topic.do?topicKey=gi_dis/5811&selectedTitle=1~148&source=search_result#9. 
88. ^ Jackson J, O'Malley P, Tomkins G, Balden E, Santoro J, Kroenke K (2000). "Treatment of functional gastrointestinal disorders with antidepressant medications: a meta-analysis". Am J Med 108 (1): 65–72. doi:10.1016/S0002-9343(99)00299-5. PMID 11059442. 
89. ^ Drossman D, Toner B, Whitehead W, Diamant N, Dalton C, Duncan S, Emmott S, Proffitt V, Akman D, Frusciante K, Le T, Meyer K, Bradshaw B, Mikula K, Morris C, Blackman C, Hu Y, Jia H, Li J, Koch G, Bangdiwala S (2003). "Cognitive-behavioral therapy versus education and desipramine versus placebo for moderate to severe functional bowel disorders". Gastroenterology 125 (1): 19–31. doi:10.1016/S0016-5085(03)00669-3. PMID 12851867. 
90. ^ Sharara AI, Aoun E, Abdul-Baki H, Mounzer R, Sidani S, Elhajj I (2006). "A randomized double-blind placebo-controlled trial of rifaximin in patients with abdominal bloating and flatulence". Am J Gastroenterol 101 (2): 326–33. doi:10.1111/j.1572-0241.2006.00458.x. PMID 16454838. 
91. ^ Quigley EM (2006). "Germs, gas and the gut; the evolving role of the enteric flora in IBS". Am J Gastroenterol 101 (2): 334–5. doi:10.1111/j.1572-0241.2006.00445.x. PMID 16454839. 
92. ^ Warfield, Carol A.; Zahid H. Bajwa (2003). Principles and Practice of Pain Medicine. McGraw-Hill Professional. ISBN 0071443495. 
93. ^ Kennedy T, Jones R, Darnley S, Seed P, Wessely S, Chalder T (2005). "Cognitive behaviour therapy in addition to antispasmodic treatment for irritable bowel syndrome in primary care: randomised controlled trial". BMJ 331 (7514): 435. doi:10.1136/bmj.38545.505764.06. PMID 16093252. PMC 1188111. http://bmj.bmjjournals.com/cgi/content/full/331/7514/435. 
94. ^ Heymann-Mönnikes I, Arnold R, Florin I, Herda C, Melfsen S, Mönnikes H (2000). "The combination of medical treatment plus multicomponent behavioral therapy is superior to medical treatment alone in the therapy of irritable bowel syndrome". Am J Gastroenterol 95 (4): 981–94. doi:10.1111/j.1572-0241.2000.01937.x. PMID 10763948. 
95. ^ van der Veek PP, van Rood YR, Masclee AA (2007). "[www3.interscience.wiley.com/cgi-bin/fulltext/117987882/HTMLSTART Clinical trial: short- and long-term benefit of relaxation training for irritable bowel syndrome]". Aliment. Pharmacol. Ther. 26 (6): 943–52. doi:10.1111/j.1365-2036.2007.03437.x (inactive 2009-05-07). PMID 17767479. www3.interscience.wiley.com/cgi-bin/fulltext/117987882/HTMLSTART. 
96. ^ Nikfar S, Rahimi R, Rahimi F, Derakhshani S, Abdollahi M (December 2008). "Efficacy of probiotics in irritable bowel syndrome: a meta-analysis of randomized, controlled trials". Dis. Colon Rectum 51 (12): 1775–80. doi:10.1007/s10350-008-9335-z. PMID 18465170. 
97. ^ Niedzielin K, Kordecki H, Birkenfeld B (2001). "A controlled, double-blind, randomized study on the efficacy of Lactobacillus plantarum 299V in patients with irritable bowel syndrome". Eur J Gastroenterol Hepatol 13 (10): 1143–7. doi:10.1097/00042737-200110000-00004. PMID 11711768. 
98. ^ American College of Gastroenterology (October 31, 2005). "New Studies Examine the Evidence on Probiotics in IBS" (PDF). Press release. http://www.acg.gi.org/media/releases/ACG05Release_ProbioticsinIBS.pdf. 
99. ^ Brenner DM, Moeller MJ, Chey WD, Schoenfeld PS (April 2009). "The utility of probiotics in the treatment of irritable bowel syndrome: a systematic review". Am. J. Gastroenterol. 104 (4): 1033–49; quiz 1050. doi:10.1038/ajg.2009.25. PMID 19277023. 
100. ^ "IBS diet: Can yogurt ease symptoms?". Mayo Clinic. May 21, 2008. http://www.mayoclinic.com/health/ibs-diet/AN01346. 
101. ^ Madisch A, Holtmann G, Plein K, Holz J (2004). "Treatment of irritable bowel syndrome with herbal preparations: results of a double-blind, randomized, placebo-controlled, multi-centre trial". Aliment Pharmacol Ther 19 (3): 271–9. doi:10.1111/j.1365-2036.2004.01859.x. PMID 14984373. 
102. ^ Hadley SK, Gaarder SM (2005). "Treatment of irritable bowel syndrome". Am Fam Physician 72 (12): 2501–6. PMID 16370407. http://www.aafp.org/afp/20051215/2501.html. 
103. ^ Nash P, Gould SR, Bernardo DE (1986). "Peppermint oil does not relieve the pain of irritable bowel syndrome". Br J Clin Pract 40 (7): 292–3. PMID 3527248. 
104. ^ Liu JH, Chen GH, Yeh HZ, Huang CK, Poon SK (1997). "Enteric-coated peppermint-oil capsules in the treatment of irritable bowel syndrome: a prospective, randomized trial". J. Gastroenterol. 32 (6): 765–8. doi:10.1007/BF02936952. PMID 9430014. 
105. ^ "Peppermint Oil May Relieve Digestive Symptoms, Headaches". 13 April 2007. http://cme.medscape.com/viewarticle/555147. 
106. ^ Gasiorowska A, Poh CH, Fass R (2009). "Gastroesophageal Reflux Disease (GERD) and Irritable Bowel Syndrome (IBS)—Is It One Disease or an Overlap of Two Disorders?". Digestive Diseases and Sciences 54 (9): 1829-34. doi:10.1007/s10620-008-0594-2. http://www.springerlink.com/content/d70u8guh574771k8/?p=b591b9cec4e141cea24c6378d2ced122&pi=0. 
107. ^ Lim B, Manheimer E, Lao L, Ziea E, Wisniewski J, Liu J, Berman B (2006). "Acupuncture for treatment of irritable bowel syndrome". Cochrane Database Syst Rev (4): CD005111. doi:10.1002/14651858.CD005111.pub2. PMID 17054239. 
108. ^ ^{a b c} Quigley EM, Locke GR, Mueller-Lissner S, Paulo LG, Tytgat GN, Helfrich I, Schaefer E (July 2006). "Prevalence and management of abdominal cramping and pain: a multinational survey". Aliment. Pharmacol. Ther. 24 (2): 411–9. doi:10.1111/j.1365-2036.2006.02989.x. PMID 16842469. 
109. ^ Ehlin AG, Montgomery SM, Ekbom A, Pounder RE, Wakefield AJ (August 2003). "Prevalence of gastrointestinal diseases in two British national birth cohorts". Gut 52 (8): 1117–21. doi:10.1136/gut.52.8.1117. PMID 12865268. 
110. ^ Hungin AP, Chang L, Locke GR, Dennis EH, Barghout V (June 2005). "Irritable bowel syndrome in the United States: prevalence, symptom patterns and impact". Aliment. Pharmacol. Ther. 21 (11): 1365–75. doi:10.1111/j.1365-2036.2005.02463.x. PMID 15932367. 
111. ^ Jafri W, Yakoob J, Jafri N Islam M, Ali QM (June 2007). "Irritable bowel syndrome and health seeking behaviour in different communities of Pakistan". J Pak Med Assoc 57 (6): 285–7. PMID 17629228. 
112. ^ Jafri W, Yakoob J, Jafri N, Islam M, Ali QM (2005). "Frequency of irritable bowel syndrome in college students". J Ayub Med Coll Abbottabad. 4 (17): 9–11. PMID 16599025. 
113. ^ Tuteja AK, Talley NJ, Gelman SS, Alder SC, Adler SC, Thompson C, Tolman K, Hale DC (January 2008). "Development of Functional Diarrhea, Constipation, Irritable Bowel Syndrome, and Dyspepsia During and After Traveling Outside the USA". Dig. Dis. Sci 53 (1): 271–6. doi:10.1007/s10620-007-9853-x. PMID 17549631. 
114. ^ Leong SA, Barghout V, Birnbaum HG, et al. (2003). "The economic consequences of irritable bowel syndrome: a US employer perspective". Arch. Intern. Med. 163 (8): 929–35. doi:10.1001/archinte.163.8.929. PMID 12719202. 
115. ^ Martin B, Ganguly R, Pannicker S, Feride F, Barghout V (2003). "Utilization Patterns and Net Direct Medical Costs Medicaid of Irritable Bowel Syndrome". Curr Med Res Opin 19 (8): 771–80. doi:10.1185/030079903125002540. PMID 12719202. http://www.medscape.com/viewarticle/465472. 
116. ^ Brown PW (1950). "The irritable bowel syndrome". Rocky Mountain medical journal 47 (5): 343–6. PMID 15418074. 

External links

• UNC Center for Functional GI & Motility Disorders
• Irritable bowel syndrome at the Open Directory Project

v • d • e Digestive system · Digestive disease · Gastroenterology (primarily K20–K93, 530–579) Upper GI tract Esophagus Esophagitis (Candidal) · rupture (Boerhaave syndrome, Mallory-Weiss syndrome) · UES (Zenker's diverticulum) · LES (Barrett's esophagus) · Esophageal motility disorder (Nutcracker esophagus, Achalasia, Diffuse esophageal spasm, GERD) · Esophageal stricture · Megaesophagus Stomach Gastritis (Atrophic, Ménétrier's disease, Gastroenteritis) · Peptic (gastric) ulcer (Cushing ulcer, Dieulafoy's lesion) · Dyspepsia · Pyloric stenosis · Achlorhydria · Gastroparesis · Gastroptosis · Portal hypertensive gastropathy · Gastric antral vascular ectasia · Gastric dumping syndrome · Gastric volvulus Lower GI tract: Intestinal/ enteropathy Small intestine/ (duodenum/jejunum/ileum) Enteritis (Duodenitis, Jejunitis, Ileitis) — Peptic (duodenal) ulcer (Curling's ulcer) — Malabsorption: Coeliac · Tropical sprue · Blind loop syndrome · Whipple's · Short bowel syndrome · Steatorrhea · Milroy disease Large intestine (appendix/colon) Appendicitis · Colitis (Pseudomembranous, Ulcerative, Ischemic, Microscopic, Collagenous, Lymphocytic) · Functional colonic disease (IBS, Intestinal pseudoobstruction/Ogilvie syndrome) — Megacolon/Toxic megacolon · Diverticulitis/Diverticulosis Large and/or small Enterocolitis (Necrotizing) · IBD (Crohn's disease) — vascular: Abdominal angina · Mesenteric ischemia · Angiodysplasia — Bowel obstruction: Ileus · Intussusception · Volvulus · Fecal impaction — Constipation · Diarrhea (Infectious) Rectum Proctitis (Radiation proctitis) · Proctalgia fugax · Rectal prolapse Anus Anal fissure/Anal fistula · Anal abscess  · Anal dysplasia  · Pruritus ani GI bleeding/BIS Upper (Hematemesis, Melena) · Lower (Hematochezia) Accessory Liver Hepatitis (Viral hepatitis, Autoimmune hepatitis, Alcoholic hepatitis) · Cirrhosis (PBC) · Fatty liver (NASH) · vascular (Hepatic veno-occlusive disease, Portal hypertension, Nutmeg liver) · Alcoholic liver disease · Liver failure (Hepatic encephalopathy, Acute liver failure) · Liver abscess (Pyogenic, Amoebic) · Hepatorenal syndrome · Peliosis hepatis Gallbladder Cholecystitis · Gallstones/Cholecystolithiasis · Cholesterolosis · Rokitansky-Aschoff sinuses · Postcholecystectomy syndrome · Porcelain gallbladder Bile duct/ other biliary tree Cholangitis (PSC, Secondary sclerosing cholangitis, Ascending) · Cholestasis/Mirizzi's syndrome · Biliary fistula · Haemobilia · Gallstones/Cholelithiasis common bile duct (Choledocholithiasis, Biliary dyskinesia) · Sphincter of Oddi dysfunction Pancreatic Pancreatitis (Acute, Chronic, Hereditary) · Pancreatic pseudocyst · Exocrine pancreatic insufficiency · Pancreatic fistula Abdominopelvic Hernia Diaphragmatic: Congenital diaphragmatic · Hiatus — Abdominal hernia: Inguinal (Indirect, Direct) · Umbilical · Incisional · Femoral — Obturator hernia · Spigelian hernia · Internal hernia Peritoneal Peritonitis (Spontaneous bacterial peritonitis) · Hemoperitoneum · Pneumoperitoneum digestive system navs: anat of tract,glands,perit,diaphragm/physio/dev, noncongen/congen/congen of d+w/neoplasia, symptoms+signs/eponymous, proc

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