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What is IBS?

Irritable bowel syndrome (IBS) is a group of symptoms—including pain or discomfort in your abdomen and changes in your bowel movement patterns—that occur together. Doctors call IBS a functional gastrointestinal (GI) disorder. Functional GI disorders happen when your GI tract behaves in an abnormal way without evidence of damage due to a disease.

Does IBS have another name?

In the past, doctors called IBS colitis, mucous colitis, spastic colon, nervous colon, and spastic bowel. Experts changed the name to reflect the understanding that the disorder has both physical and mental causes and isn’t a product of a person’s imagination.

 

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Frequently Asked Questions About IBS

Table of Contents


What is IBS?

Irritable bowel syndrome (IBS) is a group of symptoms—including pain or discomfort in your abdomen and changes in your bowel movement patterns—that occur together. Doctors call IBS a functional gastrointestinal (GI) disorder. Functional GI disorders happen when your GI tract behaves in an abnormal way without evidence of damage due to a disease.

Does IBS have another name?

In the past, doctors called IBS colitis, mucous colitis, spastic colon, nervous colon, and spastic bowel. Experts changed the name to reflect the understanding that the disorder has both physical and mental causes and isn’t a product of a person’s imagination.


What are the four types of IBS?

Doctors often classify IBS into one of four types based on your usual stool consistency. These types are important because they affect the types of treatment that are most likely to improve your symptoms.

The four types of IBS are

  • IBS with constipation, or IBS-C
    • hard or lumpy stools at least 25 percent of the time
    • loose or watery stools less than 25 percent of the time
  • IBS with diarrhea, or IBS-D
    • loose or watery stools at least 25 percent of the time
    • hard or lumpy stools less than 25 percent of the time
  • Mixed IBS, or IBS-M
    • hard or lumpy stools at least 25 percent of the time
    • loose or watery stools at least 25 percent of the time
  • Unsubtyped IBS, or IBS-U
    • hard or lumpy stools less than 25 percent of the time
    • loose or watery stools less than 25 percent of the time


How common is IBS?

Studies estimate that IBS affects 10 to 15 percent of U.S. adults. However, only five to seven percent of U.S. adults have received a diagnosis of IBS.

Who is more likely to develop IBS?

IBS affects about twice as many women as men and most often occurs in people younger than age 45.


What other health problems do people with IBS have?

People with IBS often suffer from other GI and non-GI conditions. GI conditions such as gastroesophageal reflux disease and dyspepsia are more common in people with IBS than the general population.

Non-GI conditions that people with IBS often have include the following:

  • chronic fatigue syndrome
  • chronic pelvic pain
  • temporomandibular joint disorders
  • depression
  • anxiety
  • somatoform disorders


What are the symptoms of IBS?

The most common symptoms of irritable bowel syndrome (IBS) include pain or discomfort in your abdomen and changes in how often you have bowel movements or how your stools look. The pain or discomfort of IBS may feel like cramping and have at least two of the following:

  • Your pain or discomfort improves after a bowel movement.
  • You notice a change in how often you have a bowel movement.
  • You notice a change in the way your stools look.

IBS is a chronic disorder, meaning it lasts a long time, often years. However, the symptoms may come and go. You may have IBS if:

  • You’ve had symptoms at least three times a month for the past three months.
  • Your symptoms first started at least six months ago.

People with IBS may have diarrhea, constipation, or both. Some people with IBS have only diarrhea or only constipation. Some people have symptoms of both or have diarrhea sometimes and constipation other times. People often have symptoms soon after eating a meal.

Other symptoms of IBS include the following:

  • bloating
  • the feeling that you haven’t finished a bowel movement
  • whitish mucus in your stool

Women with IBS often have more symptoms during their menstrual periods.

While IBS can be painful, IBS doesn’t lead to other health problems or damage your gastrointestinal (GI) tract.


What causes IBS?

Doctors aren’t sure what causes IBS. Experts think that a combination of problems can lead to IBS.

Physical Problems

Brain-Gut Signal Problems

Signals between your brain and the nerves of your gut, or small and large intestines, control how your gut works. Problems with brain-gut signals may cause IBS symptoms.

GI Motility Problems

If you have IBS, you may not have normal motility in your colon. Slow motility can lead to constipation and fast motility can lead to diarrhea. Spasms can cause abdominal pain. If you have IBS, you may also experience hyperreactivity—a dramatic increase in bowel contractions when you feel stress or after you eat.

Pain Sensitivity

If you have IBS, the nerves in your gut may be extra sensitive, causing you to feel more pain or discomfort than normal when gas or stool is in your gut. Your brain may process pain signals from your bowel differently if you have IBS.

Infections

A bacterial infection in the GI tract may cause some people to develop IBS. Researchers don’t know why infections in the GI tract lead to IBS in some people and not others, although abnormalities of the GI tract lining and mental health problems may play a role.

Small Intestinal Bacterial Overgrowth

Normally, few bacteria live in your small intestine. Small intestinal bacterial overgrowth is an increase in the number or a change in the type of bacteria in your small intestine. These bacteria can produce extra gas and may also cause diarrhea and weight loss. Some experts think small intestinal bacterial overgrowth may lead to IBS. Research continues to explore a possible link between the two conditions.

Neurotransmitters (Body Chemicals)

People with IBS have altered levels of neurotransmitters—chemicals in the body that transmit nerve signals—and GI hormones. The role these chemicals play in IBS is unclear.

Younger women with IBS often have more symptoms during their menstrual periods. Post-menopausal women have fewer symptoms compared with women who are still menstruating. These findings suggest that reproductive hormones can worsen IBS problems.

Genetics

Whether IBS has a genetic cause, meaning it runs in families, is unclear. Studies have shown IBS is more common in people with family members who have a history of GI problems.

Food Sensitivity

Many people with IBS report that foods rich in carbohydrates, spicy or fatty foods, coffee, and alcohol trigger their symptoms. However, people with food sensitivity typically don’t have signs of a food allergy. Researchers think that poor absorption of sugars or bile acids may cause symptoms.

Mental Health Problems

Psychological, or mental health, problems such as panic disorder, anxiety, depression, and post-traumatic stress disorder are common in people with IBS. The link between mental health and IBS is unclear. GI disorders, including IBS, are sometimes present in people who have reported past physical or sexual abuse. Experts think people who have been abused tend to express psychological stress through physical symptoms.

If you have IBS, your colon may respond too much to even slight conflict or stress. Stress makes your mind more aware of the sensations in your colon. IBS symptoms can also increase your stress level.


How do doctors diagnose IBS?

Your doctor may be able to diagnose irritable bowel syndrome (IBS) based on a review of your medical history, symptoms, and physical exam. Your doctor may also order tests.

To diagnose IBS, your doctor will take a complete medical history and perform a physical exam.

Medical History

The medical history will include questions about the following things:

  • your symptoms
  • family history of gastrointestinal (GI) tract disorders
  • recent infections
  • medicines
  • stressful events related to the start of your symptoms

Your doctor will look for a certain pattern in your symptoms. Your doctor may diagnose IBS if you have the following symptoms:

  • your symptoms started at least six months ago
  • you’ve had pain or discomfort in your abdomen at least three times a month for the past 3 months
  • your abdominal pain or discomfort has two or three of the following features:
    • Your pain or discomfort improves after a bowel movement.
    • You notice a change in how often you have a bowel movement.
    • You notice a change in the way your stools look.

Physical Exam

During a physical exam, your doctor usually does the following things:

  • checks for abdominal bloating
  • listens to sounds within your abdomen using a stethoscope
  • taps on your abdomen checking for tenderness or pain


What tests do doctors use to diagnose IBS?

In most cases, doctors don’t need to perform tests to diagnose IBS. Your doctor may perform a blood test to check for other conditions or problems. Your doctor may perform more tests based on the results of the blood test and if you have the following:L

  • a family history of celiac disease, colon cancer, or inflammatory bowel disease
  • a fever
  • anemia
  • bleeding from your rectum
  • weight loss

Blood test

Doctors use blood tests to check for conditions or problems other than IBS. A health care professional sends your blood sample to a lab.

Stool test

A stool test is the analysis of a sample of stool. Your doctor will give you a container for catching and holding a stool sample. You will receive instructions on where to send or take the kit for analysis, to check for blood or parasites. Your doctor may also check for blood in your stool by examining your rectum during your physical exam.

Flexible sigmoidoscopy

Flexible sigmoidoscopy is a procedure that uses a flexible, narrow tube with a light and tiny camera (called a sigmoidoscope) on one end to look inside your rectum and lower colon.

This procedure can show signs of conditions or problems in the lower GI tract. During the procedure, the doctor can take a biopsy. You won’t feel the biopsy.

Colonoscopy

Colonoscopy is a procedure that uses a long, flexible, narrow tube with a light and tiny camera (called a colonoscope) on one end to look inside your rectum and colon.

Colonoscopy can show irritated or swollen tissue, ulcers, polyps, and cancer. A trained specialist performs this procedure.

Lower GI series

A lower GI series, also called a Barium Enema, uses X-rays to look at your large intestine.

During a lower GI series, you’ll be asked to lie on a table while the doctor inserts a flexible tube into your anus. The doctor will fill your large intestine with barium. You may be asked to change positions several times during the test.


How do doctors treat IBS?

Though irritable bowel syndrome (IBS) doesn’t have a cure, your doctor can manage the symptoms with a combination of diet, medicines, probiotics, and therapies for mental health problems. You may have to try a few treatments to see what works best for you. Your doctor can help you find the right treatment plan.

Changes in eating, diet, and nutrition

Changes in eating, diet, and nutrition, such as following a FODMAP diet, can help treat your symptoms.

Medicines

Your doctor may recommend medicine to relieve your symptoms.

  • Fiber supplements to relieve constipation when increasing fiber in your diet doesn’t help.
  • Laxatives to help with constipation. Laxatives work in different ways, and your doctor can recommend a laxative that’s right for you.
  • Loperamide to reduce diarrhea by slowing the movement of stool through your colon. Loperamide is an antidiarrheal that reduces diarrhea in people with IBS, though it doesn’t reduce pain, bloating, or other symptoms.
  • Antispasmodics, such as hyoscine, cimetropium, and pinaverium, help to control colon muscle spasms and reduce pain in your abdomen. 
  • Antidepressants, such as low doses of tricyclic antidepressants and selective serotonin reuptake inhibitors, to relieve IBS symptoms, including abdominal pain. In theory, because of their effect on colon transit, tricyclic antidepressants should be better for people with IBS with diarrhea, or IBS-D, and selective serotonin reuptake inhibitors should be better for people with IBS with constipation, or IBS-C, although studies haven’t confirmed this theory. Tricyclic antidepressants work in people with IBS by reducing their sensitivity to pain in the gastrointestinal (GI) tract as well as normalizing their GI motility and secretion.
  • Lubiprostone (Amitiza) for people who have IBS-C to improve abdominal pain or discomfort and constipation symptoms. 
  • Linaclotide (Linzess) for people who have IBS-C to relieve abdominal pain and increase how often you have bowel movements.
  • The antibiotic rifaximin to reduce bloating by treating small intestinal bacterial overgrowth. However, experts are still debating and researching the use of antibiotics to treat IBS.
  • Coated peppermint oil capsules to reduce IBS symptoms.

Follow your doctor’s instructions when you use medicine to treat IBS. Talk with your doctor about possible side effects and what to do if you have them.

Some medicines can cause side effects. Ask your doctor and your pharmacist about side effects before taking any medicine. 

Probiotics

Your doctor may also recommend probiotics. Probiotics are live microorganisms—tiny organisms that can be seen only with a microscope. These microorganisms, most often bacteria, are like the microorganisms that are normally present in your GI tract. Studies have found that taking large enough amounts of probiotics, specifically Bifidobacteria and certain probiotic combinations, can improve symptoms of IBS. However, researchers are still studying the use of probiotics to treat IBS.

You can find probiotics in dietary supplements, such as capsules, tablets, and powders, and in some foods, such as yogurt.

Discuss your use of complementary and alternative medical practices, including probiotics and dietary supplements, with your doctor.

Therapies for mental health problems

Psychological therapies may improve your IBS symptoms.

Managing Stress

Learning to reduce stress can help improve IBS. With less stress, you may find you have less cramping and pain. You may also find it easier to manage your symptoms.

Some options for managing stress include the following:

  • taking part in stress reduction and relaxation therapies such as meditation
  • getting counseling and support
  • taking part in regular exercise such as walking or yoga
  • reducing stressful life situations as much as possible
  • getting enough sleep

Talk Therapy

Talk therapy may reduce stress and improve your IBS symptoms. Two types of talk therapy that health care professionals use to treat IBS are cognitive behavioral therapy and psychodynamic, or interpersonal, therapy. Cognitive behavioral therapy focuses on your thoughts and actions. Psychodynamic therapy focuses on how your emotions affect your IBS symptoms. This type of therapy often involves relaxation and stress management techniques.

Gut-Directed Hypnotherapy

In gut-directed hypnotherapy, a therapist uses hypnosis to help you relax the muscles in the colon.

Mindfulness Training

Mindfulness training can teach you to focus your attention on sensations occurring at the moment and to avoid catastrophizing, or worrying about the meaning of those sensations.


How can my diet treat the symptoms of IBS?

Eating smaller meals more often, or eating smaller portions, may help your irritable bowel syndrome (IBS) symptoms. Large meals can cause cramping and diarrhea if you have IBS.

Eating foods that are low in fat and high in carbohydrates, such as pasta, rice, whole-grain breads and cereals, fruits, and vegetables, may help.

Fiber may improve constipation symptoms caused by IBS because it makes stool soft and easier to pass. Fiber is a part of foods such as whole-grain breads and cereals, beans, fruits, and vegetables. The U.S. Department of Agriculture and U.S. Department of Health and Human Services state in its Dietary Guidelines for Americans, 2010 that adults should get 22 to 34 grams of fiber a day.

While fiber may help constipation, it may not reduce the abdominal discomfort or pain of IBS. In fact, some people with IBS may feel a bit more abdominal discomfort after adding more fiber to their diet. Add foods with fiber to your diet a little at a time to let your body get used to them. Too much fiber at once can cause gas, which can trigger symptoms in people with IBS. Adding fiber to your diet slowly, by 2 to 3 grams a day, may help prevent gas and bloating.


What should I avoid eating to ease IBS symptoms?

Certain foods or drinks may make symptoms worse, such as the following:

  • foods high in fat
  • some milk products
  • drinks with alcohol or caffeine
  • drinks with large amounts of artificial sweeteners
  • beans, cabbage, and other foods that may cause gas

To find out if certain foods trigger your symptoms, keep a diary and track the following things:

  • what you eat during the day
  • what symptoms you have
  • when symptoms occur

Take your notes to your doctor and talk about which foods seem to make your symptoms worse. You may need to avoid these foods or eat less of them.

Your doctor may recommend that you try a special diet—called low FODMAP or FODMAP—to reduce or avoid certain foods containing carbohydrates that are hard to digest. Examples of high FODMAP foods and products you may reduce or avoid include the following:

  • fruits such as apples, apricots, blackberries, cherries, mango, nectarines, pears, plums, and watermelon, or juice containing any of these fruits
  • canned fruit in natural fruit juice, or large quantities of fruit juice or dried fruit
  • vegetables such as artichokes, asparagus, beans, cabbage, cauliflower, garlic and garlic salts, lentils, mushrooms, onions, and sugar snap or snow peas
  • dairy products such as milk, milk products, soft cheeses, yogurt, custard, and ice cream
  • wheat and rye products
  • honey and foods with high-fructose corn syrup
  • products, including candy and gum, with sweeteners ending in “–ol,” such as
    • sorbitol
    • mannitol
    • xylitol
    • maltitol*

*Courtesy: This content is provided and made available by National Institute of Diabetes and Digestive and Kidney Diseases