Role of food intolerance and effect of protease inhibitor in patients with irritable bowel syndrome (IBS)

INTERVENTION: Camostat mesilate 200mg (t.i.d.) will be administrated for 14 days. Rectal barostat measurements will be performed before and the end of the intervention. Placebo (t.i.d.) will be administrated for 14 days. Rectal barostat measurements will be performed before and the end of the intervention. CONDITION: Irritable bowel syndrome (IBS) PRIMARY OUTCOME: Adequate relief (AR) at the end of the intervention SECONDARY OUTCOME: Symptom severity at the end of the intervention INCLUSION CRITERIA: Patients who met Rome III diagnostic criteria for IBS