What Is Irritable Bowel Syndrome (Definition and Facts)?
- Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder.
- IBS is not the same as inflammatory bowel disease (IBD), a more serious condition that causes inflammation in the digestive tract and can result in severe complications.
- Symptoms of IBS include
- The cause of irritable bowel syndrome is currently unknown. It is thought to result from a combination of abnormal gastrointestinal (GI) tract movements, increased awareness of bodily functions, and a disruption in the communication between the brain and the GI tract.
- IBS-D is irritable bowel syndrome with diarrhea. Symptoms most common with IBS-D include:
- Sudden urges to have bowel movements
- Abdominal pain or discomfort
- Intestinal gas (flatulence)
- Loose stools
- Frequent stools
- A feeling of being unable to completely empty bowels
- IBS-C is irritable bowel syndrome with constipation. Symptoms most common with IBS-C include:
- Hard, lumpy stools
- Straining during bowel movements
- Infrequent stools
- There is a new blood test that may help doctors diagnose some forms of irritable bowel syndrome.
- IBS is diagnosed by exclusion, which means a doctor considers other alternatives first, performing tests to rule out other medical problems.
- Home remedies for IBS include avoiding certain foods that "trigger" or worsen diarrhea, bloating and gas such as cruciferous vegetables (for example, cauliflower, wasabi, kale, and broccoli), and legumes (for example, black beans, edamame, soy nuts, and fava beans).
- Other home remedies to relieve symptoms of IBS include adding fiber to the diet, drinking plenty of water, avoiding soda, eating smaller meals, and eating more low fat and high carbohydrate foods.
- There is currently no known cure for IBS. Medical treatment for irritable bowel syndrome includes antispasmodic medicines, antidiarrheal medicines, antidepressants, laxatives, and other drugs.
- Irritable bowel syndrome is a chronic (long-term) disease, and symptoms usually recur.
- Irritable bowel syndrome has also been called spastic colon, functional bowel disease, and mucous colitis though. IBS is not a true "colitis." The term colitis refers to a different group of conditions such as ulcerative colitis, Crohn's disease, microscopic colitis, and ischemic colitis. These are other types of bowel disease.
What Causes IBS?
- IBS is not contagious, inherited, or cancerous. It occurs more often in women than in men, and the onset occurs before the age of 35 in about half of the cases. IBS occurs in 5% to 20% of children.
- IBS also has developed after episodes of gastroenteritis.
- It has been suggested that IBS is caused by dietary allergies or food sensitivities, but this has not been proven.
- Genetics also is suggested as a potential cause of IBS, but so far a hereditary link has not been found.
- Symptoms of irritable bowel syndrome may worsen during periods of stress or during menstruation, but these factors are unlikely to be the cause that leads to the development of IBS.
What Are the Signs and Symptoms of IBS?
IBS affects each person differently. The hallmark of IBS in adults and children is abdominal discomfort or pain. The following signs and symptoms also are common:
- Abdominal cramping and pain that are relieved with bowel movements
- Alternating periods of diarrhea and constipation
- Those who mostly have diarrhea as a symptom are considered to have IBS with diarrhea (IBS-D), characterized by sudden urges to have bowel movements, along with loose stools, frequent stools, abdominal pain and discomfort, gas, and the feeling of being unable to completely empty the bowels. In severe cases of IBS-D, individuals may lose control of their bowels.
- Those who mostly have constipation as a symptom are considered to have IBS with constipation (IBS-C), characterized by passage of hard, lumpy stools, straining during bowel movements, and infrequent stools
- Change in the stool frequency or consistency
- Gassiness (flatulence)
- Passing mucus from the rectum
- Abdominal distension
- Loss of appetite
Though not a symptom of IBS, indigestion affects up to 70% of people with IBS.
The following are NOT signs and symptoms or characteristics of IBS (but should still be brought to the attention of a health-care professional since they may be signs and symptoms of other conditions):
Who Gets IBS?
Risk factors for IBS include:
- Abnormal (too fast or slow, or too strong) movements of the colon and small intestines
- Hypersensitivity to pain caused by gas or full bowels
- A viral or bacterial infection of the stomach and intestines (gastroenteritis)
- Small intestinal bacterial overgrowth (SIBO)
- Reproductive hormones or neurotransmitters may be off-balance in people with IBS.
Anxiety or depression may accompany IBS, though these have not been found to be a direct cause of IBS.
Are IBS and IBD the Same Bowel Condition?
Irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) are not the same condition. Technically, IBS is not a disease, but rather a functional disorder (abnormal function of the bowels) that results in a group of symptoms.
Irritable bowel syndrome and inflammatory bowel disease can have similar symptoms, but IBS is less serious than IBD. IBS does not cause inflammation, intestinal bleeding, rectal bleeding, ulcers, permanent damage to the intestines, or complications that can occur with IBD.
When Should You Seek Medical Care for IBS?
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 professional should be consulted. Go to a hospital emergency department if problems are severe and/or come on suddenly.
How Do You Know If You Have IBS - Tests?
IBS can be difficult to diagnose. 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), and endoscopy and/or colonoscopy). An endoscopy is a procedure in which a flexible tube with a tiny camera at 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.
Two relatively new blood antibody blood tests may help doctors and other medical specialists diagnose irritable bowel syndrome with diarrhea or IBS-D, and irritable bowel syndrome mixed or IBS-M (irritable bowel syndrome with constipation and diarrhea).
These new blood tests are for anti-CdtB and anti-vinculin antibodies, which researchers believe, are thought to develop in some patients after having had acute) acute gastroenteritis caused by several different, common types of bacteria. The overgrowth of these bacteria in the gut may trigger an immune attack on the patients’ own intestinal tissues (autoimmunity) with the ensuing inflammation and damage to the tissues, which causes IBS symptoms.
This test also may help doctors distinguish between IBS and IBD (inflammatory bowel disease), a very different type of intestinal disease that may involve the immune system.
The test appears to be of use in diagnosing patients with irritable bowel syndrome with diarrhea IBS-D, but not IBS with constipation (IBS-C). The tests appear to be specific, and if the antibodies are present, it is highly likely that the patient has IBS. However, the tests are insensitive, which means that if the antibodies are not present, the patient still may have IBS. Thus, the tests may be identifying only a subset of individuals with IBS, those with post-infectious IBS. The FDA has not approved irritable bowel syndrome, nor have they undergone rigorous scientific examination for effectiveness. The test expected to cost from $500 to over $1,000.
What Natural Home Remedies and Diet Changes Treat and Relieve IBS Symptoms?
Most people with IBS have symptoms only occasionally and the following measures may treat or soothe symptoms during a flare:
- Add fiber to the diet: Fiber 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. People with IBS-D should look for foods with more soluble fiber, the type that takes longer to digest (such as that found in oats, beans, barley, peas, apples, carrots, and citrus fruits).
- Reduce stress and anxiety: Stress and anxiety may cause IBS "flares." Health-care professionals may offer specific advice on reducing stress. The following may help reduce stress and problems associated with IBS:
- Eat regular balanced meals.
- Reduce caffeine intake.
- Exercise may help reduce stress.
- Smoking may worsen symptoms of IBS, which is another good reason to quit.
Other home remedies to soothe and lessen IBS symptoms include:
- Increase fiber in the diet
- Drink plenty of water
- Avoid soda, which may cause gas and abdominal discomfort
- Eat smaller meals to help lessen the incidence of cramping and diarrhea.
- Low fat and high carbohydrate meals such as pasta, rice, and whole grain bread may help IBS symptoms (unless the person has celiac disease).
Digestive Disorders: Common Misconceptions
What Medications Treat IBS Symptoms?
Antispasmodic medicines, such as dicyclomine (Bemote, Bentyl, Di-Spaz) and hyoscyamine (Levsin, Levbid, NuLev), are sometimes used to treat symptoms of irritable bowel syndrome. Antispasmodic medicines help slow the movements 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 the 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.
What Medications Treat Individuals That Don't Respond to IBS Drugs?
The following medications are typically reserved for patients with symptoms that do not improve with the previously mentioned treatments:
- Alosetron (Lotronex) is a restricted drug approved only for short-term treatment of women with severe, chronic, diarrhea-predominant IBS (IBS-D) 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.
- Rifaximin (Xifaxan) is an antibiotic medication for IBS-D that works by reducing or altering gut bacteria, and it can improve symptoms of bloating and diarrhea after a 10 to 14 day course of treatment. Some patients require retreatment at higher doses for symptom relief.
- Eluxadoline (Viberzi) is another newer medication for IBS-D that helps reduce abdominal pain and improves stool consistency in adults.
- Linaclotide (Linzess) is a kind of drug that relieves constipation and pain for some adults with irritable bowel syndrome (IBS). In drug trials, people with IBS with constipation (a subtype of IBS called IBS-C) had more frequent and better bowel movements and less abdominal pain after taking daily doses of Linzess. The drug often began working within the first few days of treatment.
- Lubiprostone (Amitiza) is a type of laxative used to treat severe irritable bowel syndrome with constipation (IBS-C) 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.
- 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.
New medications for IBS-D are also being developed or are in clinical trials. Those that are most promising include:
- Serotonin synthesis inhibitors may help reduce pain and improve stool consistency
- Ramosetron, similar to alosetron (Lotronex). This is reported to relieve symptoms with less constipation.
- Spherical carbon adsorbent offers short-term relief from pain and bloating, but no improvement in stool consistency.
- Benzodiazepine receptor modulator (dextofisopam) has the potential to reduce colonic motility and gut sensitivity reactions in response to stress.
- Peripheral k-agonist (asimadoline, a kappa-opioid agonist) is in clinical trials and it shows reduced pain, urgency and stool frequency.
Which Specialties of Doctors Treats IBS?
Irritable bowel syndrome may initially be diagnosed by your primary care provider such as your family doctor, internist, or family medicine specialist. A gastroenterologist (a doctor who specializes in disorders of the digestive system) usually will provide further treatment. An emergency medicine specialist may be seen if you have an acute flare-up of IBS symptoms and go to a hospital emergency room.
Is There a Specific Diet Plan for a Person with IBS?
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:
- Some vegetables (cauliflower, broccoli, cabbage, Brussels sprouts) and legumes (beans) may worsen bloating and gassiness and should be avoided.
- A high fiber diet 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 bread may help (unless you have celiac disease).
- Probiotic supplements such as lactobacillus acidophilus or prebiotics may help alleviate IBS symptoms including abdominal pain, bloating, and bowel movement irregularity.
- A diet low in FODMAPs (Fermentable Oligo-saccharides, Di-saccharides, Mono-saccharides, and Polyols), a group of short-chain carbohydrates, may help relieve IBS symptoms. Consult your doctor for more information.
What Foods Should You Avoid If You Have IBS?
Whether you have IBS-D or IBS-C, there are foods to avoid that may trigger symptoms.
Certain foods may worsen bloating and gassiness. Foods to avoid include cruciferous vegetables and legumes, such as:
- Brussels sprouts
- Bok choy
- Chinese cabbage
- Collard greens
Legumes also may worsen gassiness and bloating, for example:
- Black beans
- Black-eyed peas
- Chickpeas (garbanzo beans)
- Fava beans
- Lima beans
- Red kidney beans
- Soy nuts
Some foods may trigger symptoms of abdominal cramps and diarrhea, including:
- Fatty foods
- Fried foods
- Sorbitol (a sweetener found in many diet foods, candies, and gums)
- Fructose (found naturally in honey and some fruits, and also used as a sweetener)
Eating large meals may also trigger abdominal cramping and diarrhea.
What Other Lifestyle Changes Help Relieve IBS symptoms?
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.
- Exercise regularly.
- Stop smoking for overall good health.
- Avoid coffee/caffeine 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
- Gut-directed hypnosis can reduce stress and anxiety
- Biofeedback teaches you to recognize your body's responses to stress and you can learn to slow your heart rate and relax.
- Pain management techniques can improve tolerance to pain
- Cognitive behavioral therapy or psychotherapy with trained counselors
What Are the Complications of Irritable Bowel Syndrome?
IBS has few associated complications. IBS does not lead to rectal bleeding, colon cancer, or inflammatory bowel diseases including ulcerative colitis. Diarrhea and constipation may aggravate hemorrhoids in people who already have them. If a person eliminates too many foods from their diet, and the diet is too limited in nutrients that could cause health problems.
The effect on a person's quality of life is the biggest complication of IBS. Stress and anxiety can result from the pain and can impact a person's daily life.
Can Irritable Bowel Syndrome Be Prevented?
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.
What Is the Prognosis for a Person with IBS?
Because irritable bowel syndrome is a chronic (long-term) disease, symptoms usually return from time to time. This may be influenced by factors such as stress, diet, or other environmental causes. No known treatment cures IBS. Multiple factors may play a role in aggravating IBS, so it is difficult to predict what triggers may make IBS worse in a particular person. Establishing a good relationship with a health-care professional may help alleviate concerns over symptoms and allow rapid recognition of changing or worsening symptoms.
Reviewed on 11/2/2018
Aragon G. et al. "Probiotic Therapy for Irritable Bowel Syndrome. Gastroenterology & Hepatology. 2010;6(1):39-44.
Camilleri, M. "Current and future pharmacological treatments for diarrhea-predominant irritable bowel syndrome." Expert Opinion on Pharmacotherapy, 2013. 14 (9), 1151-1160.
Crohn's & Colitis Foundation of America. "IBS and IBD: Two Very Different Disorders."
Jeffrey S. Hyams, M.D. Irritable Bowel Syndrome in Children. National Institutes of Health. Jun 25, 2014.
International Foundation for Functional Gastrointestinal Disorders. "IBS Diet: Cramping and Diarrhea." Jun 14, 2016.
International Foundation for Functional Gastrointestinal Disorders. "IBS in the Real World." Jul 26, 2016.
National Cancer Institute. "What are cruciferous vegetables?" Jun 07, 2012.