Functional Bowel Disorders

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Functional bowel disorders are characterized by gastrointestinal problems in the absence of any abnormalities on blood tests, X-rays, endoscopy, or any other investigations.

These disorders include non-cardiac chest pain, non-ulcer dyspepsia, post-cholecystectomy pain, irritable bowel syndrome, and functional abdominal pain.



The Case of...


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Causes and Risk Factors

Sexual, physical, or emotional abuse can lead to functional abdominal pain.

Life stressors, psychological state, social supports, etc...

CNS and ENS can cause changes in motility and sensation. People's behaviours are critical in this.

There appears to be positive feedback in some people with muscular contractions and pain.

Gut hypersensitivity, central sensitization, and abnormal processing all appear to contribut to pain in functional bowel diseases.

IBS patients have a decreased pain threshold.

Acute stress modulates colonic motility and blood flow: medical student.

Stress and emotions are a big deal. An irritable gut is hypersensitive and overreacts. Stress upsets the normal bowel rhythm.

This can lead to diarrhea or feelings of "butterflies in the stomach".

IBS can affect up to 12-13% of the population, and women are more susceptible. Prevalence decreases with age.

Accounts for 12% of primary care and 28% of GI practice, but a majority of people with IBS do not seek a doctor's help. It is a considerable health burden, being the 2nd most common cause of lost work time in young adults, after upper respiratory tract infections.


Functional dyspepsia


abdominal migraine

paroxysmal episodes of intense, acute periumbilical pain that lasts for 1 hour or more

intervening periods of usual health

with at least 2 of the following symptoms:


childhood functional abdominal pain syndrome

pain at least 25% of the time, severe enough to


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Signs and Symptoms

Functional bowel disorders are some of the most common causes of chronic abdominal pain.

  • history
  • physical exam



Physical Exam


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  • lab investigations
  • diagnostic imaging

Lab Investigations

Diagnostic Imaging

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Differential Diagnosis

For dyspepsia

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Consequences and Course


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The Case of...


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Additional Resources


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Topic Development







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