Irritable Bowel Syndrome (IBS)

	Topic Overview
	Health Tools
	Cause
	Symptoms
	What Happens
	What Increases Your Risk
	When To Call a Doctor
	Exams and Tests
	Treatment Overview
	Prevention
	Home Treatment
	Medications
	Surgery
	Other Treatment
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What is irritable bowel syndrome (IBS)?

Irritable bowel syndrome (IBS) is a disorder of the intestines. It causes belly pain, cramping or bloating, and diarrhea or constipation. Irritable bowel syndrome is a long-term problem, but there are things you can do to reduce your symptoms.

Your symptoms may be worse or better from day to day, but your IBS will not get worse over time. IBS does not cause more serious diseases, such as inflammatory bowel disease or cancer.

What causes IBS?

Doctors do not know exactly what causes irritable bowel syndrome. In IBS, the movement of the digestive tract does not work as it should, but there is no sign of changes in the intestines, such as inflammation or tumors. Doctors think that IBS symptoms are related to problems with the signals sent between the brain and the intestines. This causes problems with the way the muscles of the intestines move.

For some people with IBS, certain foods, stress, hormonal changes, and some antibiotics may trigger pain and other symptoms.

What are the symptoms?

The main symptoms of irritable bowel syndrome are belly pain with constipation or diarrhea. Other common symptoms are bloating, mucus in the stools, or a feeling that you have not completely emptied your bowels.

Many people with IBS go back and forth between having constipation and having diarrhea. For most people, one of these happens more often than the other.

IBS is quite common. Most people's symptoms are so mild that they never see a doctor for treatment. But some people may have troublesome symptoms, especially stomach cramps, bloating, and diarrhea.

How is IBS diagnosed?

Most of the time, doctors can diagnose irritable bowel syndrome from the symptoms. Your doctor will ask you about your symptoms and past health and will do a physical exam.

In some cases, you may need other tests, such as stool analysis or a sigmoidoscopy. A sigmoidoscopy lets a doctor look at the inside of the lower part of the intestine (the large intestine or colon). These tests can help your doctor rule out other problems that might be causing your symptoms.

How is it treated?

Irritable bowel syndrome is a long-term condition, but there are things you can do to manage your symptoms. Treatment usually includes making changes in your diet and lifestyle, such as avoiding foods that trigger your symptoms, getting regular exercise, and managing your stress.

There are also medicines that may help with your symptoms. If diet and lifestyle changes do not help enough on their own, your doctor may prescribe medicines for pain, diarrhea, or constipation.

Frequently Asked Questions

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	Irritable bowel syndrome: Controlling symptoms with diet

The exact cause of irritable bowel syndrome (IBS) is not known. However, health experts believe faulty communication between the brain and the intestinal tract causes the symptoms of IBS.

A complex combination of elements, including psychological stress, hormones, the immune system, and chemicals called neurotransmitters, appears to interfere with messages between the brain and the bowel. The miscommunication causes abnormal muscle contractions or spasms, which often cause cramping pain. The spasms may either speed the passage of stool, causing diarrhea, or slow it down, causing constipation or bloating.

People who have IBS seem to have unusually sensitive intestines. It is not known why their intestines are more likely to react strongly to the elements that contribute to IBS. People who have IBS may start having symptoms because of one or more factors, including:

• Eating (though no particular foods have been associated with IBS).
• Stress. Stress may affect the movements of the intestines and also may affect the way a person feels pain. (Stress may also have the same effect on people who do not have IBS.)
• Trapped gas that causes bloating.
• Hormonal changes, such as during the menstrual cycle.
• Some medicines, such as antibiotics.
• Genetics. IBS may be more likely to occur in people who have a family history of the disorder.

An expert panel has outlined a list of symptoms common in irritable bowel syndrome (IBS). Doctors often use this list of symptoms, known as the Rome III criteria, to distinguish IBS from other intestinal problems. However, people who don't have all of these symptoms may still have IBS.

You meet the Rome III criteria for IBS if your symptoms began at least 6 months ago, you have had abdominal pain or discomfort at least 3 days each month in the last 3 months, and at least two of the following statements are true:¹

• The pain is relieved by having a bowel movement.
• The pain is linked to a change in how often you have a bowel movement.
• The pain is linked to a change in the appearance or consistency of your stool.

The presence of any of the following symptoms supports a diagnosis of IBS.

Bowel movement patterns

When you have IBS, your pattern of bowel movements may be different over time. Two or more of the following may happen:

• Bowel movements may occur either more often (diarrhea) or less often (constipation) than usual, such as having more than 3 bowel movements a day or less than 3 a week.
• Bowel movements may differ in size or consistency (may be hard and pelletlike, pencil-thin, or loose and watery).
• The way stools pass changes. You may strain, feel an urgent need to have a bowel movement, or feel that you haven't completely passed a stool.
• You may have bloating or a feeling of gas in the intestines.

Other intestinal symptoms

Some people may have lower abdominal pain with constipation that is sometimes followed by diarrhea. Other people have pain and mild constipation but no diarrhea.

Symptoms that are sometimes present include intestinal gas and passage of mucus in stools.

Nongastrointestinal symptoms

You may sometimes have other symptoms that don't affect the intestines, such as:

• Anxiety or depression.
• Fatigue.
• Headache.
• Unpleasant taste in the mouth.
• Backache.
• Sleeping problems (insomnia) not caused by symptoms of IBS.
• Sexual problems, such as pain during sex or reduced sexual desire.
• Heart palpitations (feeling like the heart skips a beat or is fluttering).
• Urinary symptoms (frequent or urgent need to urinate, trouble starting the urine stream, trouble emptying the bladder).

Symptoms often occur after a meal, during stressful times, or during menstruation.

There are many other conditions with symptoms similar to IBS.

Symptoms of irritable bowel syndrome (IBS) may persist for a long time, but IBS does not cause cancer or shorten life expectancy.

The pattern of IBS varies from one person to the next and from one bout to the next. Some people have symptoms off and on for many years. You may go months or years without having any symptoms. However, most people have recurrent episodes of symptoms. It is rare for a person to have symptoms constantly.

As people get older, their symptoms of IBS tend to get better. And over time about 3 out of 10 people will stop having any symptoms at all.²

Although IBS does not cause more serious conditions, such as cancer or inflammatory bowel disease, a person who has IBS may also have one of these illnesses.

It is estimated that between 10% and 15% of people in North America have irritable bowel syndrome (IBS).³ Only about 30% of people with IBS will consult a doctor about their symptoms.⁴

IBS tends to be more common in:

• People in their late 20s.
• Women. IBS is two times more common in women than in men.³
• People who have panic disorder or other psychological conditions.
• People who have a family history of IBS.
• People who have a history of physical or sexual abuse or other psychological trauma. Several studies have found a link between a past history of abuse and gastrointestinal disorders.⁵
• People with other conditions such as depression, migraine headaches, and fibromyalgia (which causes widespread muscle and soft-tissue pain and tenderness).

Call your doctor or other health professional if:

• You have been diagnosed with irritable bowel syndrome (IBS) and your symptoms become worse, begin to disrupt your activities, or do not respond as usual to your home treatment.
• You are becoming more tired than usual.
• Your symptoms wake you from sleep.
• You have unexplained weight loss.
• You have decreased appetite.
• You have abdominal pain that is not associated with changes in bowel function or that is not relieved when you pass gas or a stool.
• You have abdominal pain that is now in one area (localized) more than any other area.
• You see blood in your stool.

Watchful Waiting

Watchful waiting is not appropriate if you have any "alarm symptoms," which could indicate a serious problem. Alarm symptoms include:

• Fever.
• Unexplained weight loss.
• Blood in your stools.
• Anemia, which is a decrease in the amount of oxygen-carrying substance (hemoglobin) found in red blood cells.
• Family history of colon cancer or inflammatory bowel disease, which causes chronic inflammation of the intestines.

If none of the symptoms listed above is present, try to rule out other causes of abdominal problems, such as eating a new food; eating sugar-rich foods, especially milk products; eating foods containing sorbitol or other artificial sweeteners; nervousness; or stomach flu. Try home treatment for 1 or 2 weeks. If your symptoms don't get better or if they get worse, call your health professional.

An occasional case of upset stomach, diarrhea, or constipation is common, especially during stressful times. Symptoms of stomach pain, nausea, vomiting, and diarrhea that come on quickly and that go away on their own are more likely to be caused by stomach flu or food poisoning, especially if other people around you are also sick.

Who To See

The following health professionals can diagnose and treat irritable bowel syndrome (IBS).

• General practitioner
• Family medicine doctor
• Internist

If more tests are needed or your symptoms do not respond to initial therapy, it may be helpful to see a doctor who specializes in treating digestive system problems (gastroenterologist). If stress may be playing a role in IBS, it may be helpful to see a psychiatrist or psychologist.

To prepare for your appointment, see the topic Making the Most of Your Appointment.

Irritable bowel syndrome (IBS) can be diagnosed based on symptoms. In most cases, only minimal tests are needed. A health professional diagnoses IBS when a person has the typical symptoms of the disorder and, if needed, tests have ruled out other possible causes.

The amount of testing that may be done depends on several factors: your age, how your symptoms come on and how severe they are, and how you respond to the initial treatment. For example:

• For a 20-year-old woman who has all the typical symptoms of IBS, a routine blood test may be the only test needed. Irritable bowel syndrome is more common in young women, and so if symptoms are typical of IBS, extensive testing is probably not needed.
• For a 55-year-old man whose symptoms started recently, more extensive testing is probably needed. People over age 50 are less likely than younger people to develop IBS symptoms for the first time, so it is more likely that symptoms may be caused by another problem.
• If you get better after some initial treatment for symptoms that the health professional suspects are caused by IBS, no further tests are needed.

Depending on your symptoms, results of the initial tests, or your response to treatment, other tests may be done.

Should I have testing done for irritable bowel syndrome?

Tests may include:

• Medical history and physical examination.
• Complete blood count (CBC), which provides information about the kinds and numbers of red blood cells, white blood cells, and platelets in the blood; and sedimentation rate, which checks for inflammation in the body.
• Stool analysis, which may include testing for blood in the stool (fecal occult blood test), infection (stool culture), or parasites (ova and parasites test).
• Flexible sigmoidoscopy, which allows a health professional to look inside the lower part of the large intestine for abnormal growths (such as tumors or polyps), inflammation, bleeding, hemorrhoids, and other conditions (such as diverticulosis).
• Colonoscopy, which allows a doctor to look at the lining of the entire large intestine (rectum and colon) through a thin, flexible viewing instrument called a colonoscope. The colonoscope helps the doctor detect polyps, tumors, and areas of inflammation or bleeding.

Thyroid function tests are occasionally done.

In some cases, treatment with diet or medicines may not help. If diarrhea is the main symptom and it is not getting any better, a blood test for celiac disease may be done. Celiac disease is a lifelong (chronic) condition in which foods that contain gluten—a form of protein found in some grains, notably wheat, barley, and rye—damage the small intestine, making it unable to properly absorb nutrients. Celiac disease may cause symptoms similar to IBS symptoms.

If the diagnosis is unclear after routine tests and you have other symptoms or pain in an area of the abdomen that may indicate a different problem, further tests may be done to clarify the diagnosis. These tests may include:

• Upper endoscopy, which allows your doctor to look at the lining of your esophagus, stomach, and the first part of your small intestine (duodenum) through a thin, flexible viewing instrument called an endoscope. The endoscope helps your doctor look for ulcers, inflammation, tumors, infection, or bleeding.
• Upper gastrointestinal (UGI) series, which examines the upper and part of the middle portions of the digestive tract. After you swallow a "shake" made of barium and water, X-rays are taken to track the movement of the barium through the esophagus, stomach, and first part of the small intestine (duodenum) using fluoroscopy connected to a video monitor.
• Gallbladder ultrasound, which can provide a picture of the gallbladder.
• Barium enema, an X-ray examination of the large intestine (colon and rectum) or small intestine.

If results of the above tests don't show any clear problem, further testing, such as an abdominal computed tomography (CT) scan may be needed to check for inflammatory bowel disease or other problems. These tests are not discussed here. For more information, see the topic Crohn's Disease or Ulcerative Colitis, two major types of inflammatory bowel disease.

Irritable bowel syndrome (IBS) is a long-term (chronic) but manageable condition. Treatment will depend on the types of symptoms you have and their severity, as well as how they affect your daily life, and will likely involve changes to your lifestyle. It is important that you work closely with your health professional to create a treatment plan that will meet your needs. Learn all you can about your condition so you can effectively communicate concerns and questions to your health professional.

Initial treatment

No single type of treatment for irritable bowel syndrome works best for everyone. You and your health professional will need to work together to determine what may be triggering your symptoms. It will be necessary for you to adapt your lifestyle to best deal with your symptoms and still carry on with your daily activities. Let your health professional know if parts of your treatment are not helping your symptoms.

For some people who have IBS, certain foods may trigger symptoms. The following suggestions may help prevent or relieve some IBS symptoms:

• Avoid caffeine and alcohol.
• Limit your intake of fatty foods.
• If diarrhea is your main symptom, limit dairy products, fruit, and artificial sweeteners such as sorbitol or xylitol.
• Increasing fiber in your diet may help relieve constipation.
• Avoiding foods such as beans, cabbage, or uncooked cauliflower or broccoli can help relieve bloating or gas.

Irritable bowel syndrome: Controlling symptoms with diet

Getting regular, vigorous exercise (such as swimming, jogging, or brisk walking) may help reduce tension and make your bowels more regular.

Medications may be used along with lifestyle changes to manage symptoms of IBS. Medications for IBS may include anticholinergics for cramping, loperamide (Imodium) for diarrhea, antidepressants such as amitriptyline, or antianxiety agents such as paroxetine (Paxil).

If stress triggers your symptoms, some form of psychological therapy or stress management may help you deal more positively with stress and help prevent or reduce stress-related IBS episodes.

Should I have testing done for irritable bowel syndrome?

Ongoing treatment

Treatment for irritable bowel syndrome (IBS) usually involves long-term management of your symptoms. It is important that you have a good working relationship with your health professional to monitor your symptoms and identify changes in your diet and lifestyle that can help relieve the symptoms. Keeping a journal of your symptoms can help you identify triggers that make symptoms worse.

Be especially aware of significant changes in symptoms, such as the appearance of blood in your stools, increased pain, severe fever, or unexplained weight loss. If any of these occur, your health professional may want to conduct additional tests to determine whether there is another cause for your symptoms.

In treating chronic IBS, it is important that you maintain the changes to lifestyle and diet that relieve symptoms. Quitting smoking, avoiding caffeine and foods that make symptoms worse, and getting regular exercise should all be permanent parts of your daily routine.

Irritable bowel syndrome: Controlling symptoms with diet

You will likely continue to take medicines as needed to treat your symptoms.

Because IBS often results from a combination of physical and stress-related factors, a treatment approach that addresses both these causes will be most successful. In addition to treating constipation or diarrhea with medications and changes to diet and lifestyle, stress management or other psychological therapy should be a major part of your treatment plan.

Treatment if the condition gets worse

If your symptoms get worse, your health professional will likely conduct more tests to determine whether there is another cause for your symptoms. Irritable bowel syndrome (IBS) does not lead to more serious conditions, such as cancer or inflammatory bowel disease, but a person with IBS may also have one of these illnesses.

Your health professional may also want you to try different medications, or different dosages of your current medications, if your symptoms are not responding to treatment.

You cannot prevent irritable bowel syndrome (IBS). However, proper self-care may help minimize symptoms and perhaps extend the time between episodes. This includes quitting smoking, avoiding caffeine and foods that make symptoms worse, and getting regular exercise.

For most people who have irritable bowel syndrome (IBS), home treatment may be the best way to manage the symptoms. It is also helpful to learn all you can about IBS so you can effectively communicate concerns and questions to your health professional.

Although there currently is no cure for IBS, careful attention to diet and stress management should help keep your symptoms under control and perhaps even prevent them from coming back.

Diet modification

In many people who have IBS, eating may trigger symptoms. However, for most people, there is not a particular type of food that triggers symptoms.

Increasing the amount of fiber in your diet can help control constipation. High-fiber foods include fresh fruits (raspberries, pears, apples), fresh vegetables (peas, brussels sprouts), wheat bran, and whole-grain breads and cereals. Beans such as kidney, pinto, and garbanzo are also high-fiber foods, but they should probably be avoided if gas is one of your symptoms.

You can take steps to reduce the possibility that certain foods will cause symptoms, such as avoiding or limiting gas-producing foods (including beans and cabbage), sugarless chewing gum and candy, caffeine, and alcohol.

Irritable bowel syndrome: Controlling symptoms with diet

Stress management

If stress seems to trigger your symptoms, the following may help you better manage stress and avoid or ease some IBS episodes:

• Keep a diary or journal of your symptoms as well as life events that occur with them. This often helps clarify the connection between symptoms and stressful occasions. After you have identified certain events or situations that bring on symptoms, you can develop ways of dealing with these situations.
• Get regular, vigorous exercise (such as swimming, jogging, or brisk walking) to help reduce tension.
• A hobby or an outside activity can provide a break from stressful situations.
• Psychiatrists, psychologists, hypnotists, counselors, social workers, and biofeedback specialists can provide methods for coping with stress.

Because there are no structural problems in the intestines of people who have IBS, some people may think this means that the symptoms "are all in their head." This is not true. The pain, discomfort, and bloating are real and have many different causes that can be addressed to help relieve symptoms.

While the symptoms are quite real, psychological factors often play a role in the development of IBS. People who have IBS are more likely than people without the condition to have depression, panic disorder, or other psychological conditions.¹ Acknowledging these factors may help you and your doctor successfully manage your condition.

Medication may be used along with lifestyle changes to manage symptoms of irritable bowel syndrome (IBS).

The goal of medication treatment is to relieve your symptoms enough to prevent them from interfering with your daily activities, because it may not be possible to eliminate your symptoms. Medications may be prescribed to treat moderate to severe pain, diarrhea, or constipation that does not respond to home treatment. No single medication has been shown to be effective in relieving IBS over the long term.

Medication Choices

In most cases, the choice of medication is based on your most troublesome symptom. For example, if diarrhea is the most bothersome symptom, using antidiarrheals or anticholinergics may be helpful.

For diarrhea

Medications that may be used to treat severe diarrhea that does not improve with home treatment include:

• Antidiarrheals, such as diphenoxylate (Lomotil) and loperamide (Imodium), which slow intestinal movements.
• Bile acid binding agents (cholestyramine), which prevent bile acids from stimulating the colon, slowing the passage of stools and relieving diarrhea.
• Alosetron (Lotronex), which is used for some women who have severe diarrhea and who have not responded to other treatments. This medicine slows the movement of stools through the bowels.

For constipation

Medicines for severe constipation that does not improve with home treatment include:

• Lubiprostone (Amitiza), which works by increasing the amount of fluid in your intestines, making it easier for stool to pass.
• Osmotic laxatives (such as Milk of Magnesia and nonabsorbable sugars such as lactulose), which work by holding fluids in the intestine and drawing fluids into the intestine from other tissue and blood vessels. This extra fluid in the intestines makes the stool softer and easier to pass. Use laxatives only when recommended by your doctor.
• Polyethylene glycol (MiraLax), which helps the stool hold on to more water, making it softer and easier to pass.
• Stimulant laxatives (such as Correctol, Dulcolax, or Senokot), which speed up how fast stool moves through the intestines by irritating the lining of the intestines. Regular use of stimulant laxatives is not recommended. Stimulant laxatives change the tone and feeling in the large intestine and you can become dependent on using laxatives all the time to have a bowel movement. Use laxatives only when recommended by your doctor.

For pain and cramping

The following medicines may be used for long-term pain and cramping:

• Anticholinergics (antispasmodics), such as dicyclomine (Bentyl), which help prevent or relieve painful cramping spasms in the intestines
• Antidepressants

For anxiety or depression

The following medications may be used if your IBS causes you to have anxiety or depression:

• Antidepressants
• Antianxiety agents (benzodiazepines)

What To Think About

Few medications have proven consistently helpful and all medications have side effects, so medicine should be used for specific symptoms that disrupt your normal daily activities.

If you also have another illness, such as depression, that triggers symptoms of irritable bowel syndrome, medicine for that illness may be needed.

Alosetron, a medicine that decreases abdominal sensitivity, has been shown to relieve symptoms in some women who have severe diarrhea and who have not responded to other treatments. Although this medicine was previously removed from the market when its use was shown to contribute to ischemic bowel disease (which occurs when there is not enough blood flowing to the intestines), the U.S. Food and Drug Administration (FDA) reapproved alosetron for limited use in IBS. Specific guidelines for the use of alosetron require health professionals prescribing it to sign a certificate and patients to sign a consent form.

Surgery is not done for irritable bowel syndrome (IBS).

A wide range of other therapies has been used to treat irritable bowel syndrome (IBS). Treatment methods that help you better cope with stress can help reduce symptoms.

Other Treatment Choices

Psychological treatment

A summary of studies compared psychological treatment to other treatments for people with IBS. It showed that psychological treatment relieves IBS symptoms better than no treatment at all. The studies show that all types of psychological treatment result in some improvement in symptoms and in general well-being. These treatments include behavioral therapy, psychotherapy, hypnosis, relaxation therapy, and biofeedback as well as various combinations of these therapies.⁶

The following treatment options may help relieve symptoms of irritable bowel syndrome (IBS). These treatment methods are usually more effective if they are used along with other treatment methods, such as diet changes, stress reduction, and sometimes medication.

• Therapy.Psychotherapy and behavioral therapy have been shown to help both with stress and with the digestive symptoms and pain caused by IBS. This treatment may also help some people live better with IBS.⁷
• Hypnosis.Hypnosis has been shown to help with pain and, in some cases, with the digestive symptoms caused by IBS. Some studies also show an improvement in the anxiety caused by having IBS.⁷
• Relaxation or meditation. Relaxation training and meditation involve concentrating on a word, image, or phrase for a given length of time to reach a state of deep relaxation. Studies have shown relaxation therapy can help with symptoms of IBS such as pain, tenderness, diarrhea, and constipation.⁷ Used regularly, these techniques can help you during stressful situations. With practice, you can learn to relax easily in almost any setting.
• Biofeedback.Biofeedback training, combined with some of the other psychological treatments listed above, has been studied as treatment for IBS. Improvement in symptoms, such as pain, was shown in some of the studies.⁷

Complementary treatment

Because IBS is so different for each person and because no medicines have been proven to work really well for IBS, many people try alternative or complementary treatments. Some of these treatments have been studied and some have not. The evidence to support their use varies as much as the evidence seen when medicines for IBS are studied.

• Herbal therapies, including Ayurvedic medicine and Chinese herbal medicine, may improve the symptoms of IBS. This has been shown in many studies of herbal therapy for IBS.⁸
• Acupuncture is used as a treatment for IBS. But the effectiveness of acupuncture in treating IBS is still unknown.⁹
• Peppermint oil has also been used to treat IBS. Studies have shown that peppermint oil works better than a placebo to improve symptoms by preventing cramps and spasms in the intestines.⁷
• Aloe is commonly used for IBS, especially IBS with constipation. There is currently no evidence for the use of aloe as an effective treatment for IBS.
• Ginger has been used to treat nausea and has been studied as a treatment for nausea caused by seasickness and surgery. It is not known how well ginger helps in IBS.

Antibiotics

Experts are studying whether antibiotics may relieve symptoms of IBS. One small study showed that the antibiotic rifaximin (Xifaxan) relieved the symptoms of stomach bloating and gas. More studies are needed to show if antibiotics relieve long-term symptoms.¹⁰

What To Think About

Some people have been successful at handling stressful situations and controlling their symptoms after trying psychological therapies. These techniques are not harmful and have no side effects. Some of them can be used before a stressful event to prevent or reduce symptoms.

• Celiac Disease
• Crohn's Disease
• Depression
• Diverticulitis
• Diverticulosis
• Lactose Intolerance
• Stress Management
• Ulcerative Colitis

Citations

1. Longstreth GF, et al. (2006). Irritable bowel syndrome section of Functional bowel disorders. In DA Drossman et al., eds., Rome III: The Functional Gastrointestinal Disorders, 3rd ed., pp. 490–509. McLean, VA: Degnon Associates.

2. Talley NJ (2008). Functional gastrointestinal disorders: Irritable bowel syndrome, dyspepsia, and noncardiac chest pain. In L Goldman, D Ausiello, eds., Cecil Medicine, 23rd ed., pp. 990–998. Philadelphia: Saunders Elsevier.

3. American College of Gastroenterology Functional Gastrointestinal Disorders Task Force (2002). Evidence-based position statement on the management of irritable bowel syndrome in North America. American Journal of Gastroenterology, 97(11, Suppl): S1–S26.

4. Olden KW (2002). Diagnosis of irritable bowel syndrome. Gastroenterology, 122(6): 1701–1714.

5. Tack J (2006). Irritable bowel syndrome. In MM Wolfe et al., eds., Therapy of Digestive Disorders, 2nd ed., pp. 701–710. Philadelphia: Saunders Elsevier.

6. Brandt LJ, et al. (2002). Systematic review on the management of irritable bowel syndrome in North America. American Journal of Gastroenterology, 97(11, Suppl): S7–S26.

7. Spanier JA, et al. (2003). A systematic review of alternative therapies in the irritable bowel syndrome. Archives of Internal Medicine, 163(3): 265–274.

8. Liu JP, et al. (2006). Herbal medicines for treatment of irritable bowel syndrome. Cochrane Database of Systematic Reviews (1). Oxford: Update Software.

9. Lim B, et al. (2006). Acupuncture for treatment of irritable bowel syndrome. Cochrane Database of Systematic Reviews (4). Oxford: Update Software.

10. Sharara AI, et al. (2006). A randomized double-blind placebo-controlled trial of rifaximin in patients with abdominal bloating and flatulence. American Journal of Gastroenterology, 101(2): 326–333.

Other Works Consulted

• Chang I, et al. (2005). A dose-ranging, phase II study of the efficacy and safety of alosetron in men with diarrhea-predominant IBS. American Journal of Gastroenterology, 100(1): 115–123.

• Friedel D, et al. (2001). Ischemic colitis during treatment with alosetron. Gastroenterology, 120(2): 557–560.

• Spanier JA, et al., (2003). A systematic review of alternative therapies in the irritable bowel syndrome. Archives of Internal Medicine, 163: 265–274.

• Talley NJ (2006). Irritable bowel syndrome. In M Feldman et al., eds., Sleisenger and Fordtran's Gastrointestinal and Liver Disease, 8th ed., vol. 2, pp. 2633–2652. Philadelphia: Saunders Elsevier.