Annette N Webb, Renata Kukuruzovic, Anthony G Catto‐Smith, Susan M Sawyer

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder of unknown aetiology. Current pharmacological treatments have limited value. Hypnotherapy has been reported to have beneficial effects for IBS symptoms. To evaluate the efficacy of hypnotherapy for the treatment of irritable bowel syndrome. Published and unpublished randomised clinical trials and quasi-randomised clinical trials were identified through structured searches of MEDLINE (1966 to March 2006), EMBASE (1980 to March 2006), PsycINFO (1806 to March 2006), CINAHL (Cumulative Index to Nursing and Allied Health Literature, 1982 to March 2006), AMED (Allied and Complementary Medicine Database, 1985 to March 2006) and The Cochrane Central Register of Controlled trials. Conference proceedings from Digestive Disease Week (1980 to 2005) were also searched. Eligible studies included all randomised and quasi-randomised clinical studies comparing hypnotherapy for the treatment of irritable bowel syndrome with no treatment or another therapeutic intervention. All studies were evaluated for eligibility for inclusion. Included studies were assessed for quality and data were extracted independently by four authors. The primary outcome measure of interest was the overall bowel symptom severity score which combines abdominal pain, diarrhoea or constipation and bloating. Secondary outcomes included abdominal pain, diarrhoea, constipation, bloating, quality of life, patient's overall assessment of well-being, psychological measures as per validated questionnaires, and adverse events. Four studies including a total of 147 patients met the inclusion criteria. Only one study compared hypnotherapy to an alternative therapy (psychotherapy and placebo pill), two studies compared hypnotherapy with waiting-list controls and the final study compared hypnotherapy to usual medical management. Data were not pooled for meta-analysis due to differences in outcome measures and study design. The therapeutic effect of hypnotherapy was found to be superior to that of a waiting list control or usual medical management, for abdominal pain and composite primary IBS symptoms, in the short term in patients who fail standard medical therapy. Harmful side-effects were not reported in any of the trials. However, the results of these studies should be interpreted with caution due to poor methodological quality and small size. The quality of the included trials was inadequate to allow any conclusion about the efficacy of hypnotherapy for irritable bowel syndrome. More research with high quality trials is needed.