Hi Xavier. Thanks for your query. Since you are suffering from pain in abdomen for a couple of years, I would advise you the following: First of a consultation with a Surgical Specialist as a proper detailed hisotry and physical examination will give us a clue to the probable investigations to be done and the treatment to be planned. Investigations: *Routine blood investigations like Complete blood picture, blood sugar, urea, creatinine, liver function tests, thyroid function tests. *Urine -routine and microscopy *Stool: routine, microscopy, occult blood, culture and sensitivity. *Ultrasonography of abdomen, *Colonoscopy All these investigations should be within normal limits for one to say you have IBS Additional CT scan of the abdomen will help us to get a proper diagnosis.