Irritable Bowel Syndrome

Irritable Bowel Syndrome Overview

Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder of unknown cause. Common symptoms include abdominal cramping or pain, bloating and gassiness, and altered bowel habits.

Irritable bowel syndrome has also been called spastic colon, functional bowel disease, and mucous colitis. However, IBS is not a true "colitis." The term colitis refers to a separate group of conditions known as inflammatory bowel disease (IBD).

Irritable bowel syndrome is not contagious, inherited, or cancerous. It is estimated that 20% of adults in the U.S. have symptoms of IBS. It occurs more often in women than in men, and the onset occurs before the age of 35 in about half of the cases.

Irritable Bowel Syndrome Causes

The cause of irritable bowel syndrome is currently unknown. IBS is thought to result from an interplay of abnormal gastrointestinal (GI) tract movements, increased awareness of normal bodily functions, and a change in the nervous system communication between the brain and the GI tract. Abnormal movements of the colon, whether too fast or too slow, are seen in some, but not all, people who have IBS.

Irritable bowel syndrome has also developed after episodes of gastroenteritis.

It has been suggested that IBS is caused by dietary allergies or food sensitivities, but this has never been proven.

Symptoms of irritable bowel syndrome may worsen during periods of stress or menses, but these factors are unlikely to be the cause that leads to the development of IBS.

Irritable Bowel Syndrome Symptoms

Irritable bowel syndrome affects each person differently. The hallmark of IBS is abdominal discomfort or pain. The following symptoms are also common:

• Abdominal cramping and pain that are relieved with bowel movements
• Alternating periods of diarrhea and constipation
• Change in the stool frequency or consistency
• Gassiness (flatulence)
• Passing mucus from the rectum
• Bloating
• Abdominal distension

The following are NOT symptoms or characteristics of IBS (but should still be brought to the attention of a physician since they may be signs and symptoms of other conditions):

• Blood in stools or urine
• Black or tarry stools
• Vomiting (rare, though may occasionally accompany nausea)
• Pain or diarrhea that interrupts sleep
• Fever
• Weight loss

When to Seek Medical Care

If a person has any of the symptoms of IBS as discussed previously, or if a person with known IBS has unusual symptoms, a health care practitioner should be consulted. Go to a hospital emergency department if problems are severe and/or come on suddenly.

Irritable Bowel Syndrome Diagnosis

Irritable bowel syndrome can be a very difficult diagnosis to make. IBS is called a diagnosis of exclusion, which means a doctor considers many other alternatives first, performing tests to rule out other medical problems. Some of these tests may include laboratory studies, imaging studies (such as a CT scan or small intestinal X-rays), or a lower GI endoscopy (colonoscopy). An endoscopy is a procedure in which a flexible tube with a tiny camera on one end is passed into the GI tract while the patient is under conscious sedation.

• A combination of history, physical examination, and selected tests are used to help diagnose irritable bowel syndrome.
• No single blood test or x-ray study confirms a diagnosis of IBS.

Irritable Bowel Syndrome Treatment

Irritable Bowel Syndrome Self-Care at Home

Many people may have already modified their diets before seeing a doctor. Temporarily avoiding dairy products may help assess whether symptoms of lactose intolerance are mimicking those of irritable bowel syndrome. Persons who avoid dairy products should exercise and consider taking calcium supplements.

• Certain foods, such as cruciferous vegetables (cauliflower, broccoli, cabbage, brussels sprouts) and legumes (beans) may worsen bloating and gassiness.
• Dietary fiber may lessen symptoms.
• Individuals with IBS should drink plenty of water, and avoid soda, which may cause gas and abdominal discomfort.
• Eating smaller meals may lessen the incidence of cramping and diarrhea.
• Low fat and high carbohydrate meals such as pasta, rice, and whole grain breads may help IBS symptoms (unless the affected individual has celiac disease).

Medical Treatment

Most people with irritable bowel syndrome have problems only occasionally. A few may experience long-lasting problems and require prescription medications.

• A common treatment for IBS is the addition of fiber to the diet. This theoretically expands the inside of the digestive tract, reducing the chance it will spasm as it transmits and digests food. Fiber also promotes regular bowel movements, which helps reduce constipation. Fiber should be added gradually, because it may initially worsen bloating and gassiness.
• Stress may cause IBS "flares." Doctors may offer specific advice on reducing stress. Regularly eating balanced meals and exercising may help reduce stress and problems associated with irritable bowel syndrome.
• Smoking may worsen symptoms of IBS, which gives smokers another good reason to quit.
• Since many patients with irritable bowel syndrome report food intolerances, a food diary may help identify foods that seem to make IBS worse.
•  

Medications

• Antispasmodic medicines, such as dicycomine (Bemote, Bentyl, Di-Spaz) and hyoscyamine (Levsin, Levbid, NuLev), are sometimes used to treat symptoms of irritable bowel syndrome. Antispasmodic medicines help slow the action of the digestive tract and reduce the chance of spasms. They may have side effects and are not for everyone. Other treatment plans are available, depending on symptoms and condition.
• Antidiarrheal medicines, such as loperamide (Imodium), a kaolin/pectin preparation (Kaopectate), and diphenoxylate/atropine (Lomotil), are sometimes used when diarrhea is a major feature of IBS. Do not take these on a long-term basis without first consulting a doctor.
• Antidepressants may be very effective in smaller doses than those typically used to treat depression. Imipramine (Tofranil), amitriptyline (Elavil), nortriptyline (Pamelor), and desipramine (Norpramin) are some commonly used medicines that may alleviate irritable bowel syndrome symptoms. Some other antidepressants are more commonly prescribed when depression and IBS coexist.
• The following medications are typically reserved for patients with symptoms that do not improve with the above treatments:
• Lubiprostone (Amitiza) is a type of laxative used to treat irritable bowel syndrome with constipation in women who are at least 18 years of age. It is a capsule taken orally, twice a day with food. It is used to relieve stomach pain, bloating, and straining; and produce softer and more frequent bowel movements in people who have chronic idiopathic constipation.
• Alosetron (Lotronex) is a restricted drug approved only for short-term treatment of women with severe, chronic, diarrhea-predominant IBS who have failed to respond to conventional IBS therapy. Fewer than 5% of people with irritable bowel syndrome have the severe form, and only a fraction of people with severe IBS have the diarrhea-predominant type. Alosetron was removed from the United States market but was reintroduced with new restrictions approved by the FDA in 2002. Physicians must be registered with the pharmaceutical manufacturer in order to prescribe the medication. Serious and unpredictable gastrointestinal side effects (including some that resulted in death) were reported in association with its use following its original approval. The safety and efficacy of alosetron has not been sufficiently studied in men; therefore, the FDA has not approved the drug for treatment of IBS in men.
• Tegaserod (Zelnorm) was a medication used to treat IBS but was removed from the market in 2008 due to increased risk of heart attack, stroke, and ischemic colitis.

Irritable Bowel Syndrome Diet and Lifestyle Changes

Diet and lifestyle changes are important in decreasing the frequency and severity of IBS symptoms.

The first thing your doctor may suggest is to keep a food diary. This will help you figure out foods that trigger your symptoms.

• Limit foods that contain ingredients that can stimulate the intestines and cause diarrhea, such as:
  • Caffeine
  • Alcohol
  • Dairy products
  • Fatty foods
  • Foods high in sugar
  • Artificial sweeteners (sorbitol and xylitol)
• Some vegetables (cauliflower, broccoli, cabbage, brussels sprouts) and legumes (beans) may worsen bloating and gassiness and should be avoided.
• Dietary fiber may lessen symptoms of constipation.
• Drink plenty of water, and avoid carbonated drinks such as soda, which may cause gas and discomfort.
• Eat smaller meals and eat slowly to help reduce cramping and diarrhea.
• Low fat, high carbohydrate meals such as pasta, rice, and whole-grain breads may help (unless you have celiac disease).

In addition to dietary changes, there are some healthy habits that may also help reduce IBS symptoms.

• Maintain good physical fitness to improve bowel function and help reduce stress.
• Stop smoking for overall good health.
• Avoid coffee and chewing gum.
• Reducing or eliminating alcohol consumption may help.
• Stress management can help prevent or ease IBS symptoms.
  • Use relaxation techniques: deep breathing, visualization, yoga
  • Do things you find enjoyable: talk to friends, read, listen to music

Irritable Bowel Syndrome Prevention

Follow the diet and lifestyle recommendations as outlined above, and as discussed with your physician. Avoiding triggers is the best way to prevent symptoms of IBS.