Hello and thank you for using HCM. I have read your question and understand your concerns. Short answer: IBS diagnosis very likely! Detailed answer: From the story that you told us, it looks like Irritable Bowel Syndrome is the right diagnosis. The facts that support this conclusion include: 1) the young age of your son (mostly IBS occurs in youngsters until the age of 40); 2) Stomach ache (abdominal pain and discomfort or disturbed bowel habits are most common symptoms of IBS). In addition, in people less than 50 years old IBS is the most common diagnosed gastrointestinal condition. 3) The fact that doctors have suggested the IBS diagnosis. IBS is diagnosed based on Rome conference criteria, and therefore there is little likely for the doctors to have misdiagnosed this condition! Patients with IBS have a high probability of living free of severe symptoms in the future but symptoms usually persist for a long time; for example, after five years from the onset of disease about 95% of patients still have some symptoms. Medical intervention will have benefits for about two-thirds of patients in terms of improving symptoms and quality of life. For the treatment to be successful, psychosocial issues and patient education should be addressed, since emotional stress and psychological issues are believed to play a role in IBS apart from family history and environmental factors. I hope I have answered your question and wish you good luck!