How is IBS diagnosed?
To diagnose IBS, Dr. Jones will conduct a physical exam and take a complete medical history. The medical history will include questions about symptoms, family history of G.I. disorders, recent infections, medications, and stressful events related to the onset of symptoms. An IBS diagnosis requires that symptoms started at least 6 months prior and occurred at least three times a month for the previous 3 months. Further testing is not usually needed, though Dr. Jones may perform a blood test to screen for other problems. Additional diagnostic tests may be needed based on the results of the screening blood test and for people who also have signs such as:

• Fever
• Rectal bleeding
• Weight loss
• Anemia—too few red blood cells in the body, which prevents the body from getting enough oxygen
• Family history of colon cancer
• Family history of irritable bowel disease—long-lasting disorders that cause irritation and ulcers, or sores, in the GI tract
• Family history of celiac disease—an abnormal immune reaction to gluten, a protein found in wheat, rye, and barley, that damages the lining of the small intestine and prevents absorption of nutrients

Additional diagnostic tests may include a stool test, lower G.I. series, and flexible sigmoidoscopy or colonoscopy. Colonoscopy may also be recommended for people who are older than age 50 to screen for colon cancer.