Irritable Bowel Syndrome and Complementary Health Approaches: What the Science Says
Clinical Guidelines, Scientific Literature, Info for Patients:
Irritable Bowel Syndrome and Complementary Health Approaches
Probiotics and Prebiotics
There is some evidence that suggests some probiotics may improve symptoms of IBS; however, benefits have not been conclusively demonstrated, and not all probiotics have the same effects. Clinical guidelines issued in 2021 by the American College of Gastroenterology recommend against the use of probiotics for the treatment of global IBS symptoms. (The recommendation is conditional, with “very low level of evidence.”)
Prebiotics are specialized plant fibers that beneficially nourish the good bacteria already in the large bowel or colon. They are a nondigestible food ingredient, are not affected by heat, cold, acid, or time, and provide a wide range of health benefits. There has been increasing interest in prebiotics because they may reduce the risk for certain conditions and help improve health. However, the quality of evidence examining the effect of prebiotics in IBS is poor and more well-designed, long-term clinical trials are needed to support health claims.
What Does the Research Show?
- Clinical guidelines issued in 2021 by the American College of Gastroenterology recommend against the use of probiotics for the treatment of global IBS symptoms. (The recommendation is conditional, with “very low level of evidence.”) Authors of the guidelines noted that there are challenges in interpreting the existing literature because of small studies, the multiple types and strains of probiotics, the inconsistent benefits on individual symptoms, and the lack of rigorous trials based on U.S. Food and Drug Administration (FDA) endpoints.
- A 2022 systematic review and meta-analysis of 10 randomized controlled trials involving 757 patients with constipation-predominant IBS (IBS-C) found that compared to placebo, probiotics significantly improved stool consistency and increased the number of fecal Bifidobacteria and Lactobacillus; however, no significant differences were found in abdominal pain scores, bloating scores, or quality-of-life scores. It is important to note that only three studies included in the review were rated as having low risk of bias.
- A 2021 systematic review and meta-analysis of 9 randomized controlled trials involving 651 pediatric patients found that probiotics significantly reduced the abdominal pain score, increased the rate of abdominal pain treatment success and abdominal pain relief, and reduced the frequency of abdominal pain. But, increasing the daily intake of probiotics was not found to decrease abdominal pain further and, thus, no significant correlation between abdominal pain and the amount of probiotics ingested was found. The authors suggest that determining the most suitable probiotics may be relatively more important.
- A 2020 systematic review and meta-analysis of 35 randomized controlled trials involving 3,452 participants found that compared to placebo, probiotics improved persistent symptoms and showed beneficial effects on global IBS symptoms, including abdominal pain, bloating, and flatulence. The authors noted that there was a trend toward a beneficial effect of Bifidobacterium on global IBS symptoms and pain scores, although the strain or species responsible was uncertain.
- A 2019 review and meta-analysis of 14 studies involving a total of 1,695 participants with IBS found that daily low doses of probiotics containing Lactobacillus and Bifidobacterium microorganisms were superior to daily doses of a single probiotic or higher doses of the two probiotics.
- A 2019 systematic review of 11 studies evaluating the effects of probiotics on IBS symptoms found mixed results. Seven of the studies included in the review reported that probiotics significantly improved IBS symptoms compared with placebo, whereas the other four studies did not report any significant improvement in IBS symptoms after taking probiotics. It is important to note that three studies included in the review involved a monostrain supplement, while the remaining eight studies used a multistrain probiotic. Overall, the reviewers noted that the multistrain probiotic supplements given over 8 weeks or more appeared to produce more distinct beneficial effects.
- A 2019 randomized, double-blind, placebo-controlled, multicenter trial involving 109 patients with celiac disease on a strict gluten-free diet found that a 6-week probiotic treatment used in the study was beneficial in improving the severity of IBS-type symptoms and is associated with a modification of gut microbiota, characterized by an increase of Bifidobacterium.
- A 2019 review and analysis of 11 randomized controlled trials in 729 people with IBS or other functional bowel disorders found that taking prebiotic supplements did not improve gastrointestinal symptoms or quality of life compared to placebo. Moderate amounts of some prebiotics, specifically less than 6 grams/day of non-inulin-type fructans, improved flatulence. However, other prebiotics (inulin-type fructans) had the opposite effect; they increased flatulence in people with IBS.
- In healthy people, probiotics usually have only minor side effects, if any. However, in people with underlying health problems (for example, weakened immune systems), serious complications, such as infections, have occasionally been reported.
- Most research about safety of probiotics comes from studies of Lactobacillus and Bifidobacterium; less is known about other probiotic strains.
- While adverse events were rare, they were significantly more frequent in participants who received probiotics compared to placebo.
- Prebiotics are generally considered safe for most people. However, when taken in large doses (more than 20 grams per day for an adult), they can have side effects including flatulence, bloating, abdominal pain, cramps, and diarrhea.
Some studies have suggested benefit of gut-directed hypnotherapy for IBS symptoms, including gastrointestinal symptoms, anxiety, depression, disability, and health-related quality of life. Significant relief from pain-related functional gastrointestinal pain disorders in children has been reported after hypnotherapy compared with standard care or waitlist approaches. Clinical guidelines issued in 2021 by the American College of Gastroenterology recommend that gut-directed psychotherapies, such as gut-directed hypnotherapy, be used to treat global IBS symptoms. (The recommendation is conditional, with “very low quality of evidence.”)
What Does the Research Show?
- Clinical guidelines issued in 2021 by the American College of Gastroenterology recommend that gut-directed psychotherapies, such as gut-directed hypnotherapy, be used to treat global IBS symptoms. (The recommendation is conditional, with “very low quality of evidence.”)
- A 2020 systematic review and network meta-analysis of 41 randomized controlled trials involving a total of 4,072 participants found that gut-directed hypnotherapy was more efficacious than either education and/or support or routine care in adults with IBS. However, other psychological therapies were analyzed as well, and none was superior to another; cognitive behavioral therapy and gut-directed hypnotherapy had the largest evidence base and were the most efficacious over the long term.
- A 2022 systematic review and meta-analysis of 33 randomized controlled trials involving a total of 2,657 children with functional abdominal pain disorders found that hypnotherapy may be considered as a treatment for these disorders in childhood.
- A 2015 review of seven randomized trials of gut-directed hypnotherapy for IBS found that six of those trials reported a significant reduction in overall gastrointestinal symptoms compared to supportive therapy only. The reviewers concluded that gut-directed hypnotherapy has durable efficacy in patients with IBS, but there is not enough evidence to determine whether hypnotherapy belongs as a primary or adjunctive therapy option for patients with IBS.
- Gut-directed hypnosis is generally considered safe and tolerable among children and adults when led by licensed hypnotherapists with special training in this technique.
There is some evidence that enteric-coated peppermint oil capsules may be modestly efficacious, in the short term, in reducing several common symptoms of IBS, in particular abdominal pain, bloating, and gas. Long-term efficacy has not been established. Clinical guidelines issued in 2021 by the American College of Gastroenterology recommend the use of peppermint to provide relief of global IBS symptoms. (The recommendation is conditional, with “low quality of evidence.”)
What Does the Research Show?
- Clinical guidelines issued in 2021 by the American College of Gastroenterology recommend the use of peppermint to provide relief of global IBS symptoms. (The recommendation is conditional, with “low quality of evidence.”)
- A 2020 randomized, double-blind trial of 190 patients in the Netherlands found that neither small-intestinal-release nor ileocolonic-release peppermint oil, administered over 8 weeks, produced statistically significant reductions in abdominal pain response or overall symptom relief, when using U.S. FDA/European Medicines Agency recommended endpoints. However, the small-intestinal-release peppermint oil did produce significant reductions in abdominal pain, discomfort, and IBS severity.
- A 2020 systematic review and network meta-analysis of 51 randomized controlled trials involving 4,644 patients evaluated soluble fiber, antispasmodic drugs, peppermint oil, and gut-brain neuromodulators for IBS. The reviewers found peppermint oil was ranked first for efficacy with regard to improvement in global IBS symptoms, on the basis of data from six trials. However, the reviewers also noted that only 13 trials were at low risk of bias, and therefore, there is likely to be considerable uncertainty around these findings.
- A 2021 randomized double-blind, placebo-controlled trial involving 133 participants compared the effects of peppermint oil to placebo for relieving IBS symptoms. The results showed clinically significant improvements after 6 weeks in both groups. However, there were no statistically significant differences between peppermint oil and placebo on any of the outcome measures (improvement in IBS-Severity Scoring System scores, global improvement of IBS symptoms, and adequate relief of symptoms). Although there were no serious adverse events, there was a higher rate of adverse events, as well as adverse event-related dropouts in peppermint oil compared to placebo.
- A 2014 systematic review and meta-analysis of 9 studies involving a total of 726 participants found peppermint oil to be superior to placebo for global improvement of IBS symptoms and improvement in abdominal pain.
- Non-enteric coated forms of peppermint oil may cause or worsen heartburn symptoms, but otherwise appears to be generally safe over the short term.
There is evidence to suggest some herbal remedies improve IBS symptoms. However, much of the data available is based on studies with inadequate methodology and small sample populations.
What Does the Research Show?
- A 2021 network meta-analysis of 28 studies in 3,323 people found low-quality evidence that Chinese herbal products could be beneficial for patients with IBS in relieving their various clinical symptoms and improving their quality of life.
- A 2017 double-blind, randomized, placebo-controlled trial involving 99 participants found that those who received an herbal remedy (IQP-CL-101) containing a mixture of curcuminoids and essential oils from different Curcuma species, fish oil, peppermint oil, caraway oil, and vitamins B1, B9, and D3, had a significant reduction in IBS symptoms compared to placebo.
- A 2019 randomized trial of 240 women with diarrhea-predominant irritable bowel syndrome (IBS-D) found that crofelemer, an active compound from the latex of the plant Croton lechleri, had no significant effect compared with placebo on the number of days without pain and discomfort. However, in an analysis conducted after the trial ended, crofelemer did improve abdominal pain compared with placebo based on the FDA abdominal pain monthly responder endpoint, which suggests that crofelemer may have a role in the management of pain in IBS-D.
- A 2006 Cochrane review of 75 randomized controlled trials involving a total of 7,957 participants with IBS concluded that while some herbal remedies may improve IBS symptoms, positive findings from less rigorous trials should be interpreted with caution due to inadequate methodology, small sample sizes, and lack of confirming data.
- Herbal supplements may contain dozens of compounds and all of its ingredients may not be known.
- Some herbs can interact with medications. For example, St. John’s wort is a potent inducer of both cytochrome P-450 enzymes and intestinal P-glycoprotein. Clinically significant interactions have been documented with St. John’s wort and cyclosporine, the antiretroviral agent indinavir, oral contraceptives, coumadin, digoxin, and benzodiazepines, among others.
- Some herbs can cause serious side effects. For example, comfrey and kava can cause liver toxicity.
In sham-controlled, randomized trials, acupuncture was found to be no better than placebo for IBS symptom severity or health-related quality of life. In other studies, acupuncture appeared to provide greater benefits than two antispasmodic drugs, although the studies could not rule out that these benefits may have been due to patient preferences or expectations of improvement.
What Does the Research Show?
- A 2021 systematic review and meta-analysis of 24 studies involving 3,220 participants with IBS found that in studies that compared acupuncture to pharmacotherapy, acupuncture was superior in relieving IBS symptoms. When used as an adjuvant intervention to other treatments, including pharmacotherapy and herbal medicine, acupuncture helped to improve clinical efficacy in treating IBS symptoms. However, acupuncture was not superior to sham acupuncture for improving IBS symptoms. The authors noted that the quality of the evidence was low to moderate in the reviewed studies.
- A 2019 meta-analysis of 41 studies involving a total of 3,440 participants showed that acupuncture was no more effective than sham acupuncture for symptoms of IBS, but there was some evidence that acupuncture could be helpful when used in addition to other forms of treatment.
- A 2014 meta-analysis of six randomized, placebo-controlled trials found some benefit of acupuncture for IBS symptoms; however, only one of the six studies showed a positive effect. The authors concluded that data are insufficient to establish long-term results or to recommend acupuncture as first-line treatment.
- A 2012 Cochrane review of 17 randomized controlled trials involving a total of 1,806 participants found no evidence of an improvement with acupuncture compared to a sham acupuncture control for symptom severity or quality of life. The review also included four Chinese comparative effectiveness trials and found acupuncture to provide greater benefits than two antispasmodic drugs (pinaverium bromide and trimebutine maleate), which have been known to provide modest benefits for IBS symptoms. However, it is unclear if the benefits of acupuncture in these studies were due to patient preferences or expectation of improvement.
- Relatively few complications from using acupuncture have been reported. Still, complications have resulted from use of non-sterile needles and improper delivery of treatments.
- When not delivered properly, acupuncture can cause serious adverse effects, including infections, bleeding, pneumothorax, and injury to the central nervous system.
A small amount of evidence suggests that yoga and other types of exercise may be helpful for IBS.
What Does the Research Show?
- A 2022 Cochrane systematic review of 5 randomized controlled trials involving 218 people with IBS suggested that physical activity comprising yoga, treadmill exercise, or support to increase physical activity may improve symptoms but not quality of life or abdominal pain in people diagnosed with IBS. The authors of the study cautioned, however, that the quality of the evidence was very low.
- Yoga is generally considered a safe form of physical activity for healthy people when performed properly, under the guidance of a qualified instructor.
- Serious injuries are rare, and the most common injuries are sprains and strains. The risk of injury associated with yoga is lower than that for higher impact sports activities.
Meditation and Mindfulness
There is little research on the benefits of meditation and mindfulness for improving health in people with IBS, and the results are not conclusive.
What Does the Research Show?
- A 2018 review of 5 studies involving 695 participants with IBS concluded that in addition to receiving conventional care, an e-health mindfulness intervention along with patient education or cognitive behavioral therapy can benefit general health in people with health conditions including IBS.
- A 2019 systematic review and meta-analysis of 2 studies involving 165 participants found that those assigned to mindfulness meditation symptoms had no greater improvement compared with the control group. The authors noted that the evidence was of low quality.
- Meditation and mindfulness practices usually are considered to have few risks.
- Few studies have examined mindfulness practices for potentially harmful effects, so there is not enough evidence to make definitive statements about safety.
What Does the Research Show?
There is little research on the use of relaxation therapy for IBS, and the results are not conclusive.
- A 2021 review and analysis of 6 studies in 278 people with IBS demonstrated no difference in overall response between body-based therapy and placebo with moderate heterogeneity and low confidence in estimates.
- Relaxation techniques are generally considered safe for healthy people. In most research studies, there have been no reported negative side effects. However, occasionally, people report negative experiences such as increased anxiety, intrusive thoughts, or fear of losing control.
- Alt F, Chong P-W, Teng E, et al. Evaluation of benefit and tolerability of IQP-CL-101 (Xanthofen) in the symptomatic improvement of irritable bowel syndrome: a double-blinded, randomised, placebo-controlled clinical trial. Phytotherapy Research. 2017;31(7):1056-1062.
- Anadón A, Ares I, Martínez-Larrañaga MR, et al. Prebiotics: safety and toxicity considerations. Nutraceuticals (Second Edition). 2021. Academic Press: London. Pp. 1061-1080
- Billings W, Mathur K, Craven HJ, et al. Potential benefit with complementary and alternative medicine in irritable bowel syndrome: a systematic review and meta-analysis. Clinical Gastroenterology and Hepatology. 2021;19(8):1538-1553.e14
- Black CJ, Thakur ER, Houghton LA, et al. Efficacy of psychological therapies for irritable bowel syndrome: systematic review and network meta-analysis. Gut. 2020;69(8):1441-1451.
- Black CJ, Yuan Y, Selinger CP, et al. Efficacy of soluble fibre, antispasmodic drugs, and gut-brain neuromodulators in irritable bowel syndrome: a systematic review and network meta-analysis. The Lancet. Gastroenterology & Hepatology. 2020;5(2):117-131.
- Chao G-Q, Zhang S. Effectiveness of acupuncture to treat irritable bowel syndrome: a meta-analysis. World Journal of Gastroenterology. 2014;20(7):1870-1877.
- Dale HF, Rasmussen SH, Asiller ÖÖ, et al. Probiotics in irritable bowel syndrome: an up-to-date systematic review. Nutrients. 2019;11(9):2048.
- Ford AC, Harris LA, Lacy BE, et al. Systematic review with meta-analysis: the efficacy of prebiotics, probiotics, synbiotics and antibiotics in irritable bowel syndrome. Alimentary Pharmacology and Therapeutics. 2018;48(10):1044-1060.
- Ford AC, Lacy BE, Harris LA, et al. Effect of antidepressants and psychological therapies in irritable bowel syndrome: an updated systematic review and meta-analysis. American Journal of Gastroenterology. 2019;114(1):21-39
- Francavilla R, Piccolo M, Francavilla A, et al. Clinical and microbiological effect of a multispecies probiotic supplementation in celiac patients with persistent IBS-type symptoms: a randomized, double-blind, placebo-controlled, multicenter trial. Journal of Clinical Gastroenterology. 2019;53(3):e117-e125.
- Gordon M, Sinopoulou V, Tabbers M, et al. Psychosocial interventions for the treatment of functional abdominal pain disorders in children: a systematic review and meta-analysis. JAMA Pediatrics. 2022;176(6):560-568.
- Khanna R, MacDonald JK, Levesque BG. Peppermint oil for the treatment of irritable bowel syndrome: a systematic review and meta-analysis. Journal of Clinical Gastroenterology. 2014;48(6):505-512.
- Lacy BE, Pimentel M, Brenner DM, et al. ACG Clinical Guideline: Management of Irritable Bowel Syndrome. American Journal of Gastroenterology. 2021;116(1):17-44.
- Liang D, Longgui N, Guoqiang X. Efficacy of different probiotic protocols in irritable bowel syndrome: a network meta-analysis. Medicine. 2019;98(27):e16068.
- Liu JP, Yang M, Liu YX, et al. Herbal medicines for treatment of irritable bowel syndrome. Cochrane Database of Systematic Reviews. 2006;1:CD004116.
- Manheimer E, Cheng K, Wieland LS, et al. Acupuncture for treatment of irritable bowel syndrome. Cochrane Database of Systematic Reviews. 2012;5(5):CD005111.
- Mikolasek M, Berg J, Witt CM, et al. Effectiveness of mindfulness- and relaxation-based ehealth interventions for patients with medical conditions: a systematic review and synthesis. International Journal of Behavior Medicine. 2018;25(1):1-16.
- Moayyedi P, Ford AC, Talley NJ, et al. The efficacy of probiotics in the treatment of irritable bowel syndrome: a systematic review. Gut. 2010;59(3):325-332.
- Moser G, Trägner S, Gajowniczek EE, et al. Long-term success of GUT-directed group hypnosis for patients with refractory irritable bowel syndrome: a randomized controlled trial. American Journal of Gastroenterology. 2013;108(4):602-609.
- Nee J, Ballou S, Kelley JM, et al. Peppermint oil treatment for irritable bowel syndrome: a randomized placebo-controlled trial. American Journal of Gastroenterology. 2021;116(11):2279-2285.
- Nee J, Salley K, Ludwig AG, et al. Randomized clinical trial: crofelemer treatment in women with diarrhea-predominant irritable bowel syndrome. Clinical and Translational Gastroenterology. 2019 Dec;10(12):e00110.
- Nee J, Ballou S, Kelley JM, et al. Peppermint oil treatment for irritable bowel syndrome: a randomized placebo-controlled trial. American Journal of Gastroenterology. 2021;116(11):2279-2285
- Niu H-L, Xiao J-Y. The efficacy and safety of probiotics in patients with irritable bowel syndrome: evidence based on 35 randomized controlled trials. International Journal of Surgery. 2020;75:116-127.
- Nunan D, Cai T, Gardener AD, et al. Physical activity for treatment of irritable bowel syndrome. Cochrane Database of Systematic Reviews. 2022;6(6):CD011497. Accessed at cochranelibrary.com on March 24, 2023.
- Peters SL, Muir JG, Gibson PR. Review article: gut-directed hypnotherapy in the management of irritable bowel syndrome and inflammatory bowel disease. Alimentary Pharmacology and Therapeutics. 2015;41(11):1104-1115.
- Shang X, Fen-Fen E, Kang-Le G, et al. Effectiveness and safety of probiotics for patients with constipation-predominant irritable bowel syndrome: a systematic review and meta-analysis of 10 randomized controlled trials. Nutrients. 2022;14(12):2482.
- Wang XY, Wang H, Guan Y-Y, et al. Acupuncture for functional gastrointestinal disorders: a systematic review and meta-analysis. Journal of Gastroenterology & Hepatology. 2021;36(11):3015-3026.
- Weerts ZZRM, Masclee AAM, Witteman BJM, et al. Efficacy and safety of peppermint oil in a randomized, double-blind trial of patients with irritable bowel syndrome. Gastroenterology. 2020;158(1):123-136.
- Wilson B, Rossi M, Dimidi E, et al. Prebiotics in irritable bowel syndrome and other functional bowel disorders in adults: a systematic review and meta-analysis of randomized controlled trials. American Journal of Clinical Nutrition. 2019;109(4):1098-1111.
- Wu Y-B, Dai Y-K, Zhang L, et al. Pharmacological treatments of Chinese herbal medicine for irritable bowel syndrome in adults: a network meta-analysis of randomized controlled trials. PLoS One. 2021;16(8):e0255665.
- Xu H-L, Zou L-L, Chen M-B, et al. Efficacy of probiotic adjuvant therapy for irritable bowel syndrome in children: a systematic review and meta-analysis. PLoS One. 2021;16(8):e0255160.
- Zheng H, Chen R, Zhao X, et al. Comparison between the effects of acupuncture relative to other controls on irritable bowel syndrome: a meta-analysis. Pain Research and Management. 2019;2019:2871505.
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