The first step in making a positive diagnosis of irritable bowel syndrome (IBS) is for the doctor or other health care provider to identify if an individual has the symptoms of IBS.
This is best determined by the use of the Rome Criteria, which is a collection of the most common symptoms that typify the disorder.
This includes abdominal pain for several months that is associated with two of the following:
- the pain is relieved by defecation,
- the pain is associated with an increase or
- decrease in bowel movement frequency, and/or
- the pain is associated with the bowel movements becoming harder or softer in consistency.
The next important step is to look for signs and symptoms that are suggestive of a condition other than IBS, such as inflammatory bowel disease or celiac disease. These signs and symptoms have been referred to as “alarm signs” or “red flags.”
- anemia and other abnormal blood tests
- blood in bowel movements
- unexplained weight loss
- new onset of symptoms at the age of 50 or older
- family history of inflammatory bowel disease, colon cancer, or celiac disease
These alarm signs are usually not explained by IBS and can represent other medical problems. When these symptoms and signs occur, they should be brought immediately to the attention of a doctor who may perform additional tests.