What Is Irritable Bowel Syndrome and What Causes It?

Is IBS a Disease like Crohn’s or Inflammatory Bowel Disease?

Irritable bowel syndrome, or IBS, is a functional disorder of the gastrointestinal tract. It is not a disease like Crohn’s or inflammatory bowel disease.

Symptoms vary widely from person to person, but they may include some of the following:

• Abdominal pain, sometimes localized to lower left quadrant

• Bloating

• Diarrhea

• Constipation

• Alternating diarrhea/constipation

• Change in stool consistency or appearance

• Mucous in stool

• Feeling of incomplete evacuation after bowel movements

• Sunset onset of uncontrollable urges to have bowel movements

• Excess gas

• Pain when sitting down

• Excess gurgling/rumbling/growling in stomach and abdomen

• Nausea and vomiting

• Burping

• Loss of appetite

• Unpleasant taste in mouth

• Heartburn

• Backache

• Lethargy

• Anxiety and/or depression

• Insomnia

• Heart palpitations

• Irritable bladder or incontinence

• Gynecological problems

As you can see, it is a long list. Many of the symptoms can be caused by other illnesses or conditions. Please do not self-diagnose. See your doctor – or several, if necessary – until you have a specific diagnosis.

If you experience any of the following, get to the hospital or see a doctor immediately. They are NOT symptoms of IBS:

• High temperature

• Blood in stool or fresh bleeding with bowel movements

• Constant, unrelenting pain

Most experts agree that IBS does not cause permanent damage or lead to more serious conditions such as cancer or inflammatory bowel disease.

What Causes IBS?

After talking to several doctors, nurses, and a dietician, I received no answer to this question. There is nothing definitive on the Internet, either. However, criteria have been established that help physicians diagnose irritable bowel syndrome. Called the Rome III Criteria, you can get more information at RomeCriteria.org.

The average patient sees three doctors over three years before finally receiving a proper diagnosis.

The criteria for irritable bowel syndrome are outlined below.

• Recurrent abdominal pain or discomfort at least three days per month in the last six months, associated with two or more of the following:

– Improvement with defecation

– Onset associated with a change in frequency of stool

– Onset associated with a change in form (appearance) of stool

It is important to obtain a specific diagnosis before you assume that you have IBS. Other diseases may cause similar symptoms, and they must be ruled out before making any assumptions. There is no diagnostic test available (yet) that can prove you have irritable bowel syndrome. However, extensive examinations can rule out other, more serious conditions such as celiac disease, bowel cancer, and Crohn’s.

Other Conditions that May Affect People with IBS

According to recent research, those with IBS may also suffer from one or more of the conditions on the following list:

• Fibromyalgia syndrome (FMS)

• Chronic fatigue syndrome (CFS)

• Myofascial pain syndrome (MPS)

• Temporomandibular joint disorder (TMJ)

• Restless leg syndrome (RLS)

• Reflex sympathetic dystrophy (RSD)

• Complex regional pain syndrome (CRPS)

• Periodic limb movement (PLMS)

• Multiple chemical sensitivity syndrome (MCSS)

• Tension headaches

• Irritable bladder

• Primary dysmenorrhea

• Migraine headaches

• Vulvodynia

There may also be an overlap of conditions such as:

• Globus

• Functional chest pain

• Functional heartburn

• Functional dysphagia

• Functional dyspepsia

• Aerophagia

• Functional vomiting

• Rumination syndrome

• Functional abdominal bloating

• Functional constipation

• Functional diarrhea

• Functional abdominal pain

• Gall bladder dysfunction

• Sphincter of Oddi dysfunction

• Functional fecal incontinence

• Functional anorectal pain

• Functional defecation disorders

Functional disorders do not produce abnormal test results and nothing unusual is seen on endoscopy or x-ray. These disorders are generally diagnosed by deciding what they are NOT, and then categorizing them by symptoms.


The material provided in this article is for informational purposes only. It is not meant to replace proper medical diagnosis, treatment, or advice. Always consult your physician and other appropriate health-care providers before taking any medications, natural remedies, or supplements; or before changing your diet. Discuss all plans, symptoms, and medical conditions with your doctor.

Any use of the ideas contained herein is at your own discretion, risk, and responsibility. The author assumes no liability for any of the information presented. There are no representations or warranties, either express or implied.

You should not begin or discontinue medical treatment based on information contained in this, or any other, article.