Irritable bowel sindrome (IBS) is one of the most common gut functional diseases, affecting 10 a 20% of people. Diagnosis is based on the identificaction of symptoms according to manning, Rome I and Rome II criteria and exclusion of alarma symptoms or signs. The treatment is based on an excellent doctor-patient relatioship along with drugs targeting the predominant symptom, especially during exacerbations. For abdominal pain, antispasmodics are, at best, of only modest efficacy. Tryciclic antidepressants in low doses are useful. For diarrhea, are useful opioid antagonists, especially loperamide, but not for pain. Fyber and bulking agents may help constipation in some trials but the evidence is equivocal. Tegaserod, a 5HT4 agonist is available en many countries for use in women with IBS whose primary bowel symptom is constipation. Moreover the management of the IBS remains unsatisfactory either patients or practitioners. New drugs for IBS are needed, as currently available agents provide generally suboptimals results.