Gut-Directed Hypnotherapy is recommended in the 2008 NICE guidelines
1.2.3.1 "Referral for psychological interventions (cognitive behavioural therapy [CBT], hypnotherapy and/or psychological therapy) should be considered for people with IBS who do not respond to pharmacological treatments after 12 months and who develop a continuing symptom profile (described as refractory IBS)."
https://www.nice.org.uk/guidance/cg61/chapter/1-recommendations
Research Studies on Hypnotherapy as a treatment for IBS:
Whorwell PJ; Prior A; Faragher EB. Controlled trial of hypnotherapy in the treatment of severe refractory irritable-bowel syndrome.The Lancet 1984, 2: 1232-4. This was the earliest formal study of hypnosis treatment for IBS and remains to date one of the best studies in this research area, as it was thoroughly placebo-controlled and showed dramatically greater improvement from hypnosis treatment above the placebo. Thirty patients with severe symptoms that had been unresponsive to other treatment were randomly chosen to receive either 7 sessions of hypnotherapy (15 patients) or 7 sessions of psychotherapy plus placebo pills (15 patients). The psychotherapy group showed a small but significant improvement in abdominal pain and distension, and in general well-being but not bowel activity pattern. The hypnotherapy patients showed a dramatic improvement in all IBS symptoms. The hypnotherapy group showed no relapses during the follow-up period.
Whorwell PJ; Prior A; Colgan SM. Hypnotherapy in severe irritable bowel syndrome: further experience. Gut, 1987 Apr, 28:4, 423-5. This report summed up further experience after 35 patients were added to the initial 15 treated with hypnotherapy in their earlier 1984 Lancet study. For the whole combined 50 patient group, success rate was 95% for classic IBS cases, but substantially less for IBS patients with atypical symptom picture or significant psychological problems.
Houghton LA; Heyman DJ; Whorwell PJ. Symptomatology, quality of life and economic features of irritable bowel syndrome--the effect of hypnotherapy. Aliment Pharmacol Ther, 1996 Feb, 10:1, 91-5. This study compared 25 severe IBS patients treated with hypnosis to 25 patients with similar symptom severity treated with other methods, and demonstrated that in addition to significant improvement in all central IBS symptoms, hypnotherapy recipients had fewer visits to doctors, lost less time from work than the control group, and rated their quality of life more improved. Those patients who had been unable to work prior to treatment resumed employment in the hypnotherapy group but not in the control group. The study is notable in that it quantified the substantial economic benefits and improvement in health-related quality of life which results from hypnotherapy for IBS on top of clinical symptom improvement.
Gonsalkorale WM, Miller V, Afzal A, Whorwell PJ. Long term benefits of hypnotherapy for irritable bowel syndrome. Gut. 2003 Nov;52(11):1623-9. In this study, 204 IBS patients treated with a course of hypnotherapy completed questionnaires about symptoms, quality of life, anxiety, and depression before, immediately after, and up to six years following the treatment. Of all the treated patients, 71% showed improvement in response to treatment initially, and of those, 81% were still fully improved when re-contacted up to five years later. Quality of life and anxiety or depression scores were also still significantly improved at follow-up but showed some deterioration. Patients also reported fewer doctor visits rates and less medication use long-term after hypnosis treatment. These results indicate that for most patients the benefits from hypnotherapy last at least five years.
Galovski TE; Blanchard EB. Appl Psychophysiol Biofeedback, 1998 Dec, 23:4, 219-32. Eleven patients completed hypnotherapy, with improvement reported for all central IBS symptoms, as well as improvement in anxiety. Six of the patients were a waiting-control group for comparison, and did not show such improvement while waiting for treatment.
Vidakovic Vukic M. Hypnotherapy in the treatment of irritable bowel syndrome: methods and results in Amsterdam. Scand J Gastroenterol Suppl, 1999, 230:49-51. This paper reports the results of treatment of 27 Dutch patients treated with gut-directed hypnotherapy tailored to each individual patient. All of the 24 patients who completed treatment were found to be improved.
Gonsalkorale WM, Houghton LA, Whorwell PJ. Hypnotherapy in irritable bowel syndrome: a large-scale audit of a clinical service with examination of factors influencing responsiveness. Am J Gastroenterol 2002 Apr;97(4):954-61. This paper reported outcomes for 250 consecutive IBS patients treated in a hypnos clinic in Manchester, England, using a structured course of 12 sessions of hypnotherapy over a 3-month period plus home practice with audio recordings between sessions. Marked improvement was seen in all IBS symptoms (overall IBS severity was reduced by more than half on the average after treatment), quality of life, and anxiety and depression. All subgroups of patients appeared to do equally well except males with diarrhea, who improved far less than other patients for unknown reasons.
Palsson OS, Turner MJ, Johnson DA, Burnett CK, Whitehead WE. Hypnosis treatment for severe irritable bowel syndrome: investigation of mechanism and effects on symptoms. Dig Dis Sci 2002 Nov;47(11):2605-14. This paper describes two studies assessing the impact of hypnosis treatment using the standardized North Carolina protocol on IBS symptoms and possible physiological and psychological mechanisms underlying the treatment effects. Patients with severe IBS received seven biweekly hypnosis sessions and used hypnosis audio recordings at home in between therapy visits. Bowel pain thresholds and smooth muscle tone were measured with computer-controlled balloon inflation tests before and after treatment in 18 patients (study I), and treatment changes in heart rate, blood pressure, sweat gland activity, finger temperature, and forehead muscle activity were assessed in 24 patients (study II). Somatization, anxiety, and depression were also measured. All central IBS symptoms improved substantially from treatment in both studies. Rectal pain thresholds, rectal smooth muscle tone and autonomic functioning (except sweat gland reactivity) were unaffected by hypnosis treatment. However, the number and severity of non-gastrointestinal symptoms and psychological distress showed large decreases. Improvements in bowel symptoms were unrelated to changes in the physiological parameters measured. 17 of 18 patients in study 1 (94%) and 21 of 24 patients in study 2 (87.5%) were judged to be treatment responders. Improvement was well-maintained at 10-12 month follow up in study 2.
Al Sughayir MA. Hypnotherapy for irritable bowel syndrome in Saudi Arabian patients. East Mediterr Health J. 2007 Mar-Apr;13(2):301-8. This study investigated the effects of hypnotherapy in 26 Saudi Arabian IBS patients. Each patient completed a course of 12 weekly hypnotherapy sessions. Abdominal pain, bloating and life interference from bowel symptoms all improved significantly in the patient sample after they completed treatment. Quality of life improved more in male than in female patients, and bowel habit dissatisfaction was reduced more in females than in male patients.
Peter J, Fournier C, Keip B, Rittershaus N, Stephanou-Rieser N,Durdevic M, Dejaco C, Michalski M, Moser G. Intestinal Microbiome in Irritable Bowel Syndrome before and after Gut-Directed Hypnotherapy. Int J Mol Sci. 2018 Nov 16;19(11). pii: E3619. doi: 10.3390/ijms19113619. This was the first-ever study to examine whether the composition of gut bacteria (intestinal microbiota) in the bowels of IBS patients changes after hypnotherapy. 38 IBS patients (by Rome-III diagnostic criteria) of all IBS subtypes were treated with 10 weekly group sessions of GHT, and stool samples were collected before and after treatment for microbiota analysis. The bowel symptoms of IBS were significantly reduced on average after hypnosis treatment, and psychological distress and well-being also improved significantly. Adequate relief of IBS symptoms was reported by 84% of the patients after the hypnosis treatment. However, no significant changes were found in intestinal gut microbiota composition. The findings of this novel study suggest, perhaps not surprisingly, that hypnosis improves IBS mostly via effects that are relatively independent of microbiota composition -- most likely, through alterations in the central nervous system's control of the gut.