IBS is diagnosed based on patient reported symptoms and stool patterns. According to guidelines these criteria, patients with IBS patients will have the following symptoms:

• Must Have
  • Abdominal discomfort at least 3 days per month in the last 3 months

• Along with some or all of these
  • change in either frequency or form of stool
  • abdominal discomfort that improves after going to that bathroom
  • passage of mucous in stool

The following tests are used to confirm or rule out diagnosis

• Hydrogen breath test (HBT),  is a non-invasive test used to for small intestinal bacterial overgrowth called H.pylori. H.pylori is often thought to be related to IBS symptoms.

• Stool analysis, is a non- invasive test to rule out bleeding, parasites, etc

• Blood tests, invasive test where needle is inserted into the vein and blood sample is removed.
  • WBC (abnormal WBC would indicate possible infection)
  • Sed rate ( abnormal would indicate possible inflammation).
  • Most of the time IBS will not test positive for these two.

• Colonoscopy, is an invasive test where they insert a small camera into the anus and view the lower intestines.