Diagnosis IBS usually can be diagnosed confidently by a typical history and limited laboratory and structural evaluation. Careful attention to the description of pain and bowel habit is critical. The characteristic features form the basis for diagnostic criteria developed by multinational consensus. The characteristic symptoms alone do not always differentiate IBS from organic disease, and inquiry should be made about medication use and potential dietary factors, such as caffeine, fructose in fruit juice and sorbitol in artificially sweetened candy. Psychosocial factors, including recent stress, may influence the clinical presentation.
Physical examination reveals no explanation for the symptoms.
Diagnostic testing should be individualized according to the patient's age, predominant symptom, severity and duration of symptoms, and presence of psychosocial factors. In primary care, the emphasis should be on minimizing tests in patients with typical symptoms and no warning signs. The evaluation can be limited to that required for the physician to confidently provide explanation, reassure, and initiate therapy. Prolonged, fruitless diagnostic evaluation tends to increase patient anxiety and needlessly raises costs. In young patients, no testing or only basic blood tests, such as a complete blood count and erythrocyte sedimentation rate, may be considered.