What is Irritable Bowel Syndrome?

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder affecting bowel function, characterized by symptoms mostly relating to digestive discomfort, including diarrhea, constipation, bloating, gas, cramping, and abdominal pain. IBS affects around 11 % of the population globally. In western countries, such as the U.S., women are significantly more likely to be affected by IBS than men, but this ratio varies dramatically around the world; in India, for example, between 80 and 90 percent of those affected are male. People who have a family history of irritable bowel syndrome are more likely to develop the condition than those who do not.^[1]

Different people will experience different combinations of the possible symptoms of irritable bowel syndrome (IBS), thus requiring varying treatments. Diagnosis of IBS will involve identifying triggers of its symptoms, which are usually gastrointestinal and related to a person’s diet and lifestyle so that a person’s exposure to triggers that activate irritable bowel syndrome can be minimized as part of their treatment plan.

IBS can be a long-term condition requiring careful management. The improvement of a person’s digestive health is often brought about by a combination of lifestyle and diet changes designed to reduce instances of bloating, constipation, diarrhea, and other symptoms they may be experiencing. Changes to a person’s diet may involve adopting a low FODMAP diet; a diet low in fermentable short-chain carbohydrates. (See IBS and diet Pharmaceutical interventions may be used to treat chronic (persistent) cases of IBS.

Irritable bowel syndrome does not cause inflammation or permanent damage such as bleeding or ulcers, nor an increased risk of cancers.

Irritable bowel syndrome (IBS) vs. inflammatory bowel disease (IBD)

Both IBS and IBD are conditions that affect the gastrointestinal tract, which is part of the digestive system. Though the symptoms of IBS and IBD can be similar, including abdominal pain, bloating, constipation, diarrhea, and abdominal cramping, IBD is a more serious condition.

Inflammatory bowel diseases are a group of conditions in which the body’s own immune system attacks parts of the digestive system in the gastrointestinal tract. This group includes chronic diseases such as ulcerative colitis, which affects the large intestine, and Crohn’s disease, which can affect the entire digestive tract, damaging both the surface and the deep tissues of the intestines.^[2]

In contrast, irritable bowel syndrome (IBS) only affects the function and behavior of the intestines. IBS is not an autoimmune condition. Although IBD does not cause IBS, those affected by IBD have a greater likelihood of developing IBS than the general population. In contrast, having IBS has no impact on a person’s likelihood of developing IBD.^[2]

Irritable bowel syndrome (IBS) symptoms

Different kinds of IBS are diagnosed according to their symptoms, with people experiencing different combinations of the symptoms of irritable bowel syndrome, including bloating, diarrhea, constipation and painful abdominal cramps.

Diarrhea and constipation may each affect people with IBS on their own, together, or in alternating periods.

Common symptoms include:^[3]

Abdominal pain and cramping

Abdominal pain and cramping particularly felt in the lower belly, is one of the most common symptoms of IBS. Abdominal cramps can be caused by constipation or diarrhea, other symptoms of irritable bowel syndrome. They typically increase after meals. For some people affected by IBS, having a bowel movement (BM) can intensify pain and cramping; for others, having a BM can reduce these symptoms.

Irritable bowel syndrome (IBS) with predominant diarrhea

Some people experience diarrhea as the main symptom of irritable bowel syndrome, passing loose, watery stools more than three times per day. In people with IBS, diarrhea may occur suddenly, particularly after encountering triggers of their symptoms. In cases of irritable bowel syndrome in which a person experiences diarrhea as one of their most prominent symptoms, the condition is sometimes called IBS-D. Altering a person’s diet is the first-line treatment for IBS-D, followed by prescribing medications.^[4]

Irritable bowel syndrome (IBS) with predominant constipation

Those experiencing constipation as a symptom of IBS may pass fewer than three
bowel movements per week. When it is passed, the stool is often small and hard. When a person experiences constipation as one of the principal symptoms of irritable bowel syndrome, this is sometimes called IBS-C.

Good to know: IBS-C shares many symptoms ‒ including bloating, abdominal pain, and infrequent, difficult bowel movements ‒ with another common gastrointestinal disorder, chronic idiopathic constipation (CIC). Current research suggests that IBS-C and CIC are different conditions, despite their significantly overlapping symptoms. If a person seeks medical attention for constipation, doctors will ensure that appropriate testing is undertaken so that a differential diagnosis can be made, as these conditions require different treatment approaches to relieve constipation.^[5]

Irritable bowel syndrome (IBS) with constipation and diarrhea

When a person is equally affected by constipation and diarrhea as symptoms of irritable bowel syndrome, this is called IBS-M (mixed irritable bowel syndrome) or IBS-A (alternating irritable bowel syndrome.

Rectal tenesmus

The rectal tenesmus involves cramping and spasms in the rectum. This leads to the feeling that a bowel movement is incomplete, even if the bowel has actually been evacuated successfully. This feeling may lead to abdominal pain and cramping, associated with straining to bring about a bowel movement.

Good to know: Tenesmus is a symptom of many other gastrointestinal conditions, as well as a symptom of IBS. If a person seeks medical attention for rectal tenesmus, doctors will check for inflammation of the colon, to rule out a diagnosis such as ulcerative colitis (a form of IBD) or colon cancer.

Bloating and gas

Many people with IBS experience intense bloating (a sensation of increased abdominal pressure). This may or may not be due to an increased quantity of gas in the gastrointestinal tract; about 50 % of people experience increased abdominal pressure without a buildup of gas.^[6]

Some people with irritable bowel syndrome also experience increased burping.

Mucus in stool

Passing mucus in the stool is a common symptom of IBS, but passing blood may indicate a more serious condition affecting the bowel, colon, or gastrointestinal tract. Always seek medical attention for a prompt diagnosis if blood is present in bowel movements.

People experiencing any possible symptoms of IBS can use a List of Doctors to carry out a symptom assessment.

Causes of irritable bowel syndrome (IBS)

Despite ongoing research to determine definitive causes of IBS, these are still unclear. Contributing
factors may include infection, neurohormonal factors, food sensitivities, and bacterial overgrowth. An individual’s psychological condition, hormone changes, or stress levels are other possible causes.

Infection

It has been observed that some patients experience their first IBS symptoms after acute infectious
enteritis. This so-called postinfectious IBS may be caused by viral, bacterial, protozoan, or helminth
infection. Several research studies have shown that IBS symptoms can increase after infectious enteritis, but the actual cause of these symptoms requires further research.

Neurohormonal factors

Some people experience visceral hypersensitivity, which is a greater sensitivity to pain from the
organs, including the stretching of the bowel as gas or stool, passes through it. This may be linked
to IBS symptoms including abdominal pain, urgent bowel movements, and bloating. However, the cause of this hypersensitivity is unknown.^[7] It is also possible that the brain of a person with IBS
processes pain differently than that of an unaffected person, or that other differences in the
signals passed between the brain and the intestinal tract are related to IBS.^[8]

Neurotransmitters or reproductive hormones may be imbalanced in some people with IBS, and these may be affected by changes to an individual’s hormones, such as throughout the menstrual cycle. The possible role of sex hormones in IBS may be supported by the fact that roughly twice as many women as men are affected in some countries.^[9]

Food sensitivities

It has been observed that an individual with IBS may experience symptoms more often due to an
intolerance of foods such as wheat; dairy products; fatty, creamy or fried foods; alliums such as
garlic or onions; stone fruits and other kinds of fruit; brassicas such as cabbage, cauliflower
or Brussels sprouts; pulses such as lentils or beans and chili peppers.

Eliminating certain foods from the diet has been shown by some dietary studies to relieve the symptoms of IBS, but these foods vary according to the individual. More research on food sensitivities and their effect on IBS is required.

SIBO

Small intestine bacterial overgrowth (SIBO) is when too many of the gut’s naturally occurring
bacteria accumulate in the small intestine. Some research has linked SIBO to IBS, and that
antibiotic treatment has decreased IBS symptoms in some people with SIBO.^[10] It is not clear
from this research whether antibiotics affect the SIBO directly, or affect the IBS in a
different manner.

Malabsorption of fructose

In some people, IBS symptoms can be caused by the digestive system failing to absorb fructose effectively. Fructose is a kind of sugar found in fruits and some vegetables and is often used as an artificial sweetener in processed foods. When fructose is not absorbed properly by the digestive system, it can ferment in the colon (large intestine). This can result in gastrointestinal symptoms such as gas, bloating, and diarrhea.

For people whose IBS is believed to result from malabsorption of fructose, eating foods that are low in fructose may be helpful in reducing their symptoms. See this resource from the University of Virginia’s Digestive Health Centre for more information on low-fructose foods.

Additional factors

IBS is often linked to psychological factors such as stress, anxiety or depression, and stress
management is one possible treatment tool. Genetics may play a role in the development of IBS,
but there is limited evidence to support this.

Irritable bowel syndrome (IBS) diagnosis

A diagnosis of IBS is usually made by considering recurrence of symptoms over a period of three to six months, rather than solely through a physical examination or by visual inspection of the bowel during colonoscopy. To assist doctors in making a diagnosis, a person may keep a diary of their diet and gastrointestinal symptoms during this period, in order to identify factors that may be triggering their possible IBS.

Although it does not form the sole basis of a diagnosis of IBS, a colonoscopy may still be performed as part of an IBS diagnosis to help rule out other issues. This is an imaging procedure in which the colon or large intestine is visualized by inserting a thin, flexible tube containing a camera into the body through the rectum. See this resource on preparing for a colonoscopy for more information.

Other possible measures which may be used in making a potential diagnosis of irritable bowel syndrome include a blood or stool test, flexible sigmoidoscopy or a barium series.^[11]

People experiencing possible symptoms of IBS can also use a List of Doctors to carry out a symptom assessment.

Irritable bowel syndrome treatment

Treatments for IBS include:

Lifestyle changes

Lifestyle changes addressing diet or stress are usually the first approach to IBS treatment.

Stress and anxiety treatments

Addressing generalized stress and anxiety is a common treatment approach. Some people experience
anxiety around their IBS symptoms (known as GI symptom-specific anxiety) and may limit their
exposure to activities and situations that would be affected by their IBS. This can increase
their anxiety, creating a vicious cycle that increases their symptoms. Therapies like cognitive
behavioral therapy, psychotherapy, relaxation therapy, biofeedback, and hypnotherapy may be used
to help individuals both manage general stress and break this cycle.
Self-care to manage stress is another option, with common techniques including meditation,
yoga and exercise.

IBS and diet

Each person has different dietary triggers for IBS. If sensitivity to specific foods is a trigger
for IBS symptoms, treatment may include reducing or eliminating these foods from the diet. Many people find it helpful to avoid high-FODMAP foods; FODMAP stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, And polyols; fermentable short-chain carbohydrates which are prevalent in a regular diet, which the small intestine does not absorb very well.^[12]

Examples of low FODMAP foods which may ease symptoms of irritable bowel syndrome when included in a person’s diet include:^[12]

Lactose-free or low-lactose dairy products, such as non-dairy milk, hard cheeses such as cheddar
Low-fructose fruits such as oranges, kiwis, and strawberries
Low-fructan vegetables such as bean sprouts, carrots, eggplant, potatoes, olives, turnips
Protein such as lean meat and tofu
Gluten-free grains

Examples of high FODMAP foods, which may aggravate symptoms of irritable bowel syndrome, and should be excluded from one’s diet where possible, include:^[12]

Lactose; cow’s milk, yogurt, and cream
Fructose; fruits and products high in natural sugars from fruit, such as apples, pears, peaches, corn syrup
Fructans; vegetables and grains high in fructans include artichokes, garlic, onions, broccoli, beetroot, and grains such as wheat and rye
Polyols; sweeteners such as sorbitol and xylitol, found in sugar-free products

Another approach to alleviating symptoms of irritable bowel syndrome by changing one’s diet is to eat smaller, more frequent meals. Eating more slowly can reduce gas and bloat. Along with an individual’s possible food intolerances, foods commonly associated with abdominal cramping or diarrhea include coffee, caffeine, alcohol, or high-fat foods, as well as poorly-digested sugars, such as sorbitol or fructose. Beans, raisins, or bread can cause gas, and lactose intolerance can trigger IBS symptoms. Eating a high-fiber diet can improve stool quality and keep the GI tract healthy, but a diet excessively high in fiber can also cause gas and diarrhea.

Irritable bowel syndrome medications

Medications are available to treat moderate to severe IBS. These include:

Anti-diarrheal medications

Over-the-counter anti-diarrheal medications like loperamide (Imodium) are often used to treat IBS.
Common prescriptions drugs include diphenoxylate (Lomotil, Lomocot) and atropine.

Anticholinergic and antispasmodic medications

Antispasmodic medications such as dicyclomine (Bentyl) and hyoscyamine (Levsin), as well as
anticholinergic medications, are commonly prescribed to decrease painful abdominal spasms.
Smooth muscle relaxants, such as alverine, mebeverine, and peppermint oil may also be used.

Antidepressant medications

People affected by IBS who also have depression may be prescribed selective serotonin reuptake
inhibitors (SSRIs), such as fluoxetine (Prozac, Sarafem) or paroxetine (Paxil), as well as
tricyclic antidepressants, such as nortriptyline (Pamelor), imipramine (Tofranil) or
desipramine (Norpramin). People with IBS who do not experience depression may be also
prescribed antidepressants due to their effect on the connection between the brain and gut.

Probiotics and antibiotics

An imbalance in the normal bacteria (gut flora) living in the human gut can affect its
function and overall wellness, and probiotic supplements can introduce healthy, normal
bacteria. More research is needed to prove their overall effectiveness, but some IBS
sufferers do gain relief from the use of probiotic supplements, with Bifidobacterium
infantis the most commonly studied probiotic.

Some IBS may be associated with overgrowth or infection of harmful bacteria in the
gut, and antibiotic medications that reduce bacteria are a possible treatment. The
antibiotic Xifaxan (Rifaximin) may be used to treat this kind of IBS.

Irritable bowel syndrome FAQs

Other names for irritable bowel syndrome

• Spastic colon

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1. “The epidemiology of irritable bowel syndrome.” Clinical Epidemiology. 04 February 2014. Accessed: 27 April 2018. ↩

2. “Inflammatory bowel disease and irritable bowel syndrome: similarities and differences.” Crohn’s and Colitis Foundation of America. 2018. Accessed: 27 April 2018. ↩ ↩

3. “Irritable Bowel Syndrome.” National Institute of Diabetes and Digestive and Kidney Diseases. Accessed: September 15, 2017 ↩

4. “Diagnosis and treatment of diarrhea-predominant irritable bowel syndrome.” International Journal of General Medicine. 11 February 2016. Accessed: 27 April 2018. ↩

5. “Chronic Constipation and Constipation-Predominant IBS: Separate and Distinct Disorders or a Spectrum of Disease?” Gastroenterology & Hepatology. March 2016. Accessed: 27 April 2018. ↩

6. “Bloating.” The IBS Network. 2018. Accessed: 27 April 2018. ↩

7. “Irritable Bowel Syndrome (IBS).” National Institute of Diabetes and Digestive and Kidney Diseases. Accessed: September 15, 2017 ↩

8. “Irritable Bowel Syndrome.” National Institute of Diabetes and Digestive and Kidney Diseases. Accessed: September 15, 2017 ↩

9. “Irritable Bowel Syndrome.” National Institute of Diabetes and Digestive and Kidney Diseases. Accessed: September 15, 2017 ↩

10. “Irritable bowel syndrome clearly linked to gut bacteria.” Science Daily. Accessed: September 15, 2017 ↩

11. “Irritable Bowel Syndrome (IBS).” National Institute of Diabetes and Digestive and Kidney Diseases. Accessed: September 15, 2017 ↩

12. “Try a FODMAPs diet to manage irritable bowel syndrome.” Harvard Health Publishing. 29 July 2015. Accessed: 27 April 2018. ↩ ↩ ↩

**What is Irritable Bowel Syndrome?**



**Overview:**

Irritable bowel syndrome (IBS) ‍is a common, ⁤chronic gastrointestinal disorder that affects the large‍ intestine (colon). It is⁢ characterized by abdominal pain, bloating, gas,‌ and changes in bowel movements. IBS is not a serious ‍condition, but it can significantly impact⁢ a person’s quality of life.



**Symptoms:**

Common symptoms of IBS include:

* Abdominal pain​ and cramping

* Bloating ⁤and distension

* Gas and flatulence

* Changes ‌in bowel movements (constipation, diarrhea, or both)

*⁣ Mucus in stool



Other symptoms may‍ include:

* Fatigue

* Headaches

* Anxiety

* Difficulty sleeping



**Causes:**

The exact cause of IBS is unknown, but several factors are thought to be involved, including:

* Abnormal muscle ‌contractions in the colon

* Increased sensitivity to pain in the​ digestive tract

* Changes in gut microbiota‍ (bacteria)

* Food intolerances

* Stress and anxiety



**Risk Factors:**

Certain factors may increase the‍ risk of developing ‍IBS,⁢ such as:

* Family history

* Being female

* Age between 20 and 30

* History of gastrointestinal infections

* Stressful life events



**Diagnosis:**

IBS is diagnosed based on a person’s symptoms ‌and medical history. There‌ is no specific test for IBS. Your doctor may perform a physical‍ examination, blood tests, and stool tests ‌to ⁣rule out other medical conditions.



**Treatment:**

There is no cure forIBS, but treatment can⁤ help manage the symptoms. Treatment options‍ include:

* Diet changes: Avoiding trigger foods​ (such as certain‌ FODMAPs) can help reduce symptoms.

* Medications: ⁢Medications can help relieve pain, ‌regulate bowel movements, and reduce gas and bloating.

* Stress​ management: Stress can worsen IBS symptoms, ⁣so stress management techniques can be ⁢helpful.

* Lifestyle changes: Regular exercise, adequate sleep, ⁢and avoiding caffeine and tobacco can help improve‌ symptoms.



**Epidemiology:**

* IBS is a highly prevalent disorder, affecting up ‍to 11% of the population worldwide.

* It is more common in women than men.

* The ⁤onset ​of ⁤IBS typically occurs between the‌ ages of 20 and 30.



**Prognosis:**

IBS is a chronic condition, but it can be ⁣managed effectively with treatment. Most people with IBS can live relatively⁢ normal lives, although some may‍ experience periods of relapse.