Irritable Bowel Syndrome (IBS)

| Practice points|

• Peppermint oil capsules may signifi cantly improve symptoms of IBS• The composition of gut microbiota is disturbed and unstable in IBS patients. Probiotic supplementation improves global IBS symptom scores. Probiotic supplements are best taken with meals to enhance bacterial survival• Psyllium is commonly used to treat constipation, diarrhoea, and to regulate stool consistency. It may reduce the risk of persistent IBS symptoms

| Description |

• IBS is defi ned as a chronic functional gastrointestinal (GI) disorder characterised by altered bowel habit and abdominal discomfort without detectable structural and biochemical abnormalities1

- Altered bowel habit and abdominal pain accompany either predominantly diarrhoea, constipation, or both2

- Other comorbid conditions may include: gastro- esophageal refl ux, genito-urinary symptoms, fi bromyalgia, chronic fatigue syndrome, headache, pelvic pain, backache and psychological symptoms1,2

• IBS affects 10%-25% of the population globally2

- In Australia 13% of the population may be affected2

• Overall prevalence of IBS in women is higher than in

men3

- IBS occurs in all age groups (including children and the elderly)2• The aetiology and pathophysiology of IBS remains poorly understood and may involve many overlapping mechanisms1,4

| Management guidelines |

• Manage symptoms through dietary modifi cations, lifestyle changes, appropriate supplementation and psychological therapies such as hypnotherapy5

• Monitor condition with regular check-ups and supportive interventions5

Complementary medicines

| Primary recommendations |

PEPPERMINT OIL (Mentha piperita)

Mechanism of action• Exerts a spasmolytic effect on the smooth muscles in the digestive tract9• May relax intestinal smooth muscle cells by interfering with calcium channels9,10

• Effects may occur via attenuation of visceral hypersensitivity and modulation of pain sensation5

Research• Several small short-term trials (2 weeks-1 month) suggest daily use of 3–6 enteric-coated capsules containing 0.2–0.4 mL of peppermint oil each improves IBS symptoms11-13

• A longer clinical trial found enteric-coated peppermint oil gave signifi cant improvement in IBS symptoms compared to placebo after 4–8 weeks14,15

• These observations are supported by several

systematic reviews and meta-analyses: - A meta-analysis based on 8 trials, besides noting heterogeneous diagnostic criteria, collectively suggested effi cacy for symptom relief16

- A review of 4 small trials found overall modest symptom improvement17

- Another meta-analysis18 and systematic review5 of 4 and 5 RCTs respectively found an effect in favour of peppermint oil compared with placeboAdverse effects• Heartburn, perianal burning, nausea and vomiting may occasionally occur16

• Avoid chewing enteric-coated peppermint capsules to prevent heartburn20

• Avoid non-enteric coated peppermint in patients with refl ux oesophageal symptoms20

Interactions• Caution concomitant use with CYP3A4 enzyme

PEPPERMINT OIL (Mentha piperita)

DIGESTION

| DIGESTION | 2

substrates. Peppermint may increase blood levels of these medications19

Dosage and formulationLeaf• Infusion: 3–6 g 3 times/d20

• Liquid extract: (1:2): 1.5–4.5 mL/d20

OilDoses used in clinical trials:• Adults: 3–6 enteric coated capsules with 0.2–0.4 mL of oil10,11,13

• Adults: An enteric-coated preparation 187–225 mg 3 times/d5,12,14,15

• Children: 0.1–0.2 mL 3 times/d10,21 for no longer than 2 weeks under the guidance of a health care practitioner21

PROBIOTICS

Mechanism of action• May directly interact with intestinal microbiota to modify its composition, enhance gut barrier function and mucosal immunity, reduce mucosal permeability, and competitively exclude harmful microbes22-24

• May affect expression of opioid and cannabinoid receptors and reduce visceral hypersensitivity in intestinal epithelial cells24-26

• Reduce infl ammation, modulate the immune response, and reduce cytokine production27

Research• Clinical studies suggest that the composition of colonic microbiota is disturbed and unstable in IBS patients28-30

• A randomised, double-blind, placebo-controlled trial found treatment with a fermented milk product containing Bifi dobacterium lactis DN-173 010

decreased abdominal distension, gastrointestinal transit and reduced symptoms in IBS (constipation dominant) patients31

• These fi ndings are supported by 3 meta-analyses and 1 systematic review: - A meta-analysis of 23 trials involving 1404 patients found improvement in global IBS symptoms and abdominal pain compared with placebo32

- Two further meta-analyses showed that probiotics improved IBS symptoms33,34

- A 2015 systematic review and meta-analysis of 43 RCTs supports evidence for probiotics in improvement of overall IBS symptoms and global symptom scores although which individual species and strains are the most benefi cial remains unclear35

Adverse effects• Orally, probiotic species are well tolerated with few confi rmed adverse reactions20

Interactions• Concomitant Lactobacillus species (L. acidophilus; L. reuteri) may decrease side effects of antibiotics (positive interaction)19

• Concomitant Lactobacillus species (L.Rhamnosus GR-1; L. Reuteri RC-14) may increase drug effects of fl uconazole and may improve clinical outcome19

Dosage and formulation• Strength of Lactobacillus preparations is quantified by the number of viable living organisms, or colony-forming units (CFUs)/g: - For therapeutic efficacy: between 109

(1 billion)–1011 (150 billion) CFUs20

• Clinical studies have used various species of species of Lactobacillus and Bifidobacterium strains given in concentrations of 108-1010 CFU/d32,34

PROBIOTICS

| Secondary recommendation |

PSYLLIUM HUSK (Plantago Ovata)

Psyllium husks may decrease intra-colonic pressure and accelerate oro-anal transit5,31

• A randomised trial found that the addition of psyllium fi bre reduced IBS symptoms relative to placebo37

- A systematic review and meta-analysis (6 RCTs) suggested that soluble fi bre from blond psyllium showed favourable improvement in global IBS symptoms, and reduced risk of persistent IBS symptoms by 22% compared to placebo16

- A subsequent systematic review supported the previous fi ndings that soluble fi bres (psyllium in

particular) provide relief in IBS5

• Psyllium may initially cause mild fl atulence, bloating and abdominal discomfort which reduce with long- term use20

• Psyllium should not be consumed dry as it may cause oesophageal obstruction20

• Avoid psyllium in people with partial or complete bowel obstruction, colonic impaction, or stenosis of the GI tract20

Dosage information• In clinical studies (blond psyllium): 5–30 g/d36,37

- Stir into 150 ml water and drink immediately20

- Follow each dose with 1/2–1 glass of water20

REFERENCES 1. Saha L. Irritable bowel syndrome: pathogenesis, diagnosis, treatment, and evidence-based medicine. World J Gastroenterol 2014; 20(22):6759-73. 2. Canavan C, West J, Card T. The epidemiology of irritable bowel syndrome. Clin Epidemiol 2014; 6:71-80. 3. Lovell RM, Ford AC. Effect of gender on prevalence of irritable bowel syndrome in the community: systematic review and meta-analysis. Am J Gastroenterol 2012; 107(7):991-1000. 4. El-Salhy M. Recent developments in the pathophysiology of irritable bowel syndrome. World J Gastroenterol 2015; 21(25):7621-36. 5. Ford AC, Moayyedi P, Lacy BE. American College of Gastroenterology Monograph on the management of irritable bowel syndrome and chronic idiopathic constipation. Am J Gastroenterol 2014; 109(Suppl 1):S2-26. 6. Park SH, PhD, Han KS, et al. Relaxation therapy for irritable bowel syndrome: a systematic review. Asian Nurs Res 2014; 8(3): 182-92 7. Lee HH, Choi YY, Choi MG. The effi cacy of hypnotherapy in the treatment of irritable bowel syndrome: a systematic review and meta-analysis. J Neurogastroenterol Motil 2014; 20(2):152-62. 8. Li CY, Li SC. Treatment of irritable bowel syndrome in China: a review. World J Gastroenterol 2015; 21(8):2315-22. 9. Grigoleit HG, Grigoleit P. Pharmacology and preclinical pharmacokinetics of peppermint oil. Phytomedicine 2005; 12(8):612-6. 10. Kligler B, Chaudhary S. Peppermint oil. Am Fam Physician 2007; 75(7):1027-30. 11. Kline RM, Kline JJ, Di Palma J, et al. Enteric-coated, pHdependent peppermint oil capsules for the treatment of irritable bowel syndrome in children. J Pediatr 2001; 138(1):125-8. 12. Liu JH, Chen GH, Yeh HZ, et al. Enteric-coated peppermint-oil capsules in the treatment of irritable bowel syndrome: a prospective randomized trial. J Gastroenterol 1997; 32(6):765-8. 13. Rees WD, Evans BK, Rhodes J. Treating irritable bowel syndrome with peppermint oil. Br Med J 1979; 2(6194):835-6. 14. Cappello G, Spezzaferro M, Grossi L, et al. Peppermint oil (Mintoil) in the treatment of irritable bowel syndrome: a prospective double blind placebocontrolled randomized trial. Dig Liver Dis 2007; 39(6):530-6. 15. Merat S, Khalili S, Mostajabi P, et al. The effect of enteric-coated, delayed release peppermint oil on irritable bowel syndrome. Dig Dis Sci 2010; 55(5):1385-90. 16. Pittler MH, Ernst E. Peppermint oil for irritable bowel syndrome: a critical review and metaanalysis. Am J Gastroenterol 1998; 93(7):1131-5. 17. Spanier JA, Howden CW, Jones MP. A systematic review of alternative therapies in the irritable bowel syndrome. Arch Intern Med 2003; 163(3):265-74. 18. Ford AC, Talley NJ, Spiegel BM. Effect of fi bre, antispasmodics, and peppermint oil in the treatment of irritable bowel syndrome: systematic review and meta-analysis. BMJ 2008; 337:a2313 19. Blackmores Institute Complementary Medicines Interaction Guide; 2016 20. Braun L, Cohen M. Herbs & Natural Supplements. 3rd ed. Chatswood: Elsevier; 2010 21. Charrois TL, Hrudey J, Gardiner P, et al. Peppermint oil. Pediatr Rev 2006; 27(7):e49-51. 22. Kajander K. Pathophysiological factors of irritable bowel syndrome, and the effects of probiotic Supplementation. Academic dissertation. Faculty of Medicine, Institute of Biomedicines, Pharmacology, University of Helsinki. 2008 23. Zeng J, Li YQ, Zuo XL, et al. Clinical trial: effect of active lactic acid bacteria on mucosal barrier function in patients with diarrhoea predominant irritable bowel syndrome. Aliment Pharmacol Ther 2008; 28(8):994-1002. 24. Gerritson J, Smidt H, Rijkers GT, de Vos WM. Intestinal microbiota in human health and disease: the impact of probiotics. Genes Nutr 2011;6:209-240 25. Rousseaux C, Thuru X, Gelot A, et al. Lactobacillus acidophilus modulates intestinal pain and induces opioid and cannabinoid receptors. Nat Med. 2007; 13(1):35-7. 26. Verdu EF, Bercik P, Verma-Gandhu M, et al. Specifi c probiotic therapy attenuates antibiotic induced visceral hypersensitivity in mice. Gut. 2006; 55(2):182-90. 27. Quigley EM, Flourie B. Probiotics and irritable bowel syndrome: a rationale for their use and an assessment of the evidence to date. Neurogastroenterol Motil 2007; 19(3):166-72. 28. Malinen E, Rinttila T, Kajander K, et al. Analysis of the fecal microbiota of irritable bowel syndrome patients and healthy controls with real-time PCR. Am J Gastroenterol 2005; 100(2):373-82. 29. Maukonen J, Satokari R, Matto J, et al. Prevalence and temporal stability of selected clostridial groups in irritable bowel syndrome in relation to predominant faecal bacteria. J Med Microbiol 2006; 55(pt 5):625-33. 30. Kassinen A, Krogius-Kurikka L, Makivuokko H, et al. The fecal microbiota of irritable bowel syndrome patients differs signifi cantly from that of healthy subjects. Gastroenterology 2007; 133(1):24-33. 31. Agrawal A, Houghton LA, Morris J et al. Clinical trial: the effects of a fermented milk product containing Bifi dobacterium lactis DN-173 010 on abdominal distension and gastrointestinal transit in irritable bowel syndrome with constipation. Aliment Pharm Ther 2008;29:104-14 32. McFarland LV, Dublin S. Meta-analysis of probiotics for the treatment of irritable bowel syndrome. World J Gastroenterol 2008; 14(17):2650-61. 33. Hoveyda N, Heneghan C, Mahtani KR, et al. A systematic review and meta-analysis: probiotics in the treatment of irritable bowel syndrome. BMC Gastroenterol. 2009; 9:15. 34. Moayyedi P, Ford AC, Talley NJ, et al. The effi cacy of probiotics in the treatment of irritable bowel syndrome: a systematic review. Gut. 2010; 59(3):325-32. 35. Mazurak N, Broelz E, Storr M, et al. Probiotic therapy of the irritable bowel syndrome: why is the evidence still Poor and what can be done about it? J Neurogastroenterol Motil 2015; 21(4): 471-85. 36. Hammerle C, Surawicz C. Updates on treatment of irritable bowel syndrome. World J Gastroenterol 2008; 14(17):2639-49. 37. Bijkerk CJ, de Wit NJ, Muris JW et al. Soluble or insoluble fi bre in irritable bowel syndrome in primary care? Randomised placebo controlled trial. BMJ 2009; 339:b3154.

| Diet and lifestyle recommendations |

• Dietary increase of soluble fi bre (such as psyllium) may decrease IBS symptoms and constipation1,5

- Avoid insoluble fi bre such as bran which may exacerbate symptoms5

• Address potential food intolerances or allergies. Removing wheat/gluten, dairy, eggs, coffee, yeast, potatoes and/or citrus fruits may help relieve IBS symptoms1,5

• Decreased intake of lactose may benefi t some IBS patients1

• Reduced intake of refi ned carbohydrates and sugar-alcohols such as xylitol may assist1

• Therapies such as relaxation therapy,6 hypnotherapy,5,7 acupuncture,8 cognitive behavioural therapy,5 and yoga1 may have positive effects on physiologic IBS symptoms

• Exercise may help maintain GI function and reduce stress associated with IBS1

Contact education@blackmoresinstitute.org Healthcare Professional Advisory Service 1800 151 493 Website blackmoresinstitute.org