Only those IBS patients who had previously received a medical diagnosis of IBS and who met the Rome III criteria15 and had no evidence of organic gastrointestinal disease, including ulcerative colitis, peptic ulcer, and gastro-esophageal reflux, were eligible for participation. Defined in accordance with Rome III criteria,15 IBS was a recurrent abdominal pain or discomfort that occurred at least three months, with onset at least six months previously. In addition, two or more of the following symptoms were present; improvement with defecation; onset associated with a change in frequency of stool; onset associated with a change in form (appearance) of stool. All patients underwent thorough physical examination
and for some patients (those with diarrhea predominant IBS subtype) further diagnostic assessment were done including complete blood picture, stool analysis and culture.