Systematic Review

Probiotics in the Management of Lower Gastrointestinal Symptoms

An Updated Evidence-based International Consensus

A. P. S. Hungin; C. R. Mitchell; P. Whorwell; C. Mulligan; O. Cole; L. Agréus; P. Fracasso; C. Lionis; J. Mendive; J.-M. Philippart de Foy; B. Seifert; K.-A. Wensaas; C. Winchester; N. de Wit


Aliment Pharmacol Ther. 2018;47(8):1054-1070. 

In This Article

Abstract and Introduction


Background In 2013, a systematic review and Delphi consensus reported that specific probiotics can benefit adult patients with irritable bowel syndrome (IBS) and other gastrointestinal (GI) problems.

Aim To update the consensus with new evidence.

Methods A systematic review identified randomised, placebo–controlled trials published between January 2012 and June 2017. Evidence was graded, previously developed statements were reassessed by an 8–expert panel, and agreement was reached via Delphi consensus.

Results A total of 70 studies were included (IBS, 34; diarrhoea associated with antibiotics, 13; diarrhoea associated with Helicobacter pylori eradication therapy, 7; other conditions, 16). Of 15 studies that examined global IBS symptoms as a primary endpoint, 8 reported significant benefits of probiotics vs placebo. Consensus statements with 100% agreement and "high" evidence level indicated that specific probiotics help reduce overall symptom burden and abdominal pain in some patients with IBS and duration/intensity of diarrhoea in patients prescribed antibiotics or H. pylori eradication therapy, and have favourable safety. Statements with 70%–100% agreement and "moderate" evidence indicated that, in some patients with IBS, specific probiotics help reduce bloating/distension and improve bowel movement frequency/consistency.

Conclusions This updated review indicates that specific probiotics are beneficial in certain lower GI problems, although many of the new publications did not report benefits of probiotics, possibly due to inclusion of new, less efficacious preparations. Specific probiotics can relieve lower GI symptoms in IBS, prevent diarrhoea associated with antibiotics and H. pylori eradication therapy, and show favourable safety. This study will help clinicians recommend/prescribe probiotics for specific symptoms.


In 2013, the European Society for Primary Care Gastroenterology (ESPCG) published an evidence–based international guide for the use of probiotics in the management of specific lower gastrointestinal (GI) symptoms.[1] This guide was based on the results of a systematic review of evidence regarding the use of probiotics vs placebo in randomised controlled trials (RCTs). A Delphi panel assessed this evidence and developed a number of consensus statements. Since the publication of these statements, numerous relevant clinical studies of probiotics in the management of lower GI symptoms have been published. In the light of the new evidence available in this rapidly evolving field, the objectives of this publication are to update the systematic review and Delphi consensus, and to incorporate the new findings into the guidelines.

The importance of gut microbiota in health and disease is becoming increasingly evident, and there is a growing body of literature on the therapeutic potential of probiotics in GI disorders[2,3] like irritable bowel syndrome (IBS) and many other conditions. The proposed mechanisms of action for the beneficial effects of probiotics include competitive exclusion of pathogenic microorganisms, inhibition of pathogen adhesion, production of anti–microbial substances and modulation of the immune system.[4–6] Studies in several animal models have indicated positive therapeutic results for probiotics in a range of conditions, such as asthma,[7] obesity,[8,9] diabetes mellitus,[10] hypertension,[11,12] and depression and anxiety;[13] however, definitive data from human studies are relatively sparse. There is some evidence for a beneficial effect of probiotics in humans in the prevention of hypertension[14] and improvement of the symptoms of schizophrenia,[15] depression[16] and Alzheimer's disease,[17] although further studies are needed to confirm these findings. Evaluation of the effect of probiotics in humans is complex due to differences in strains, patient populations and dosing. In addition, many clinical trials report conflicting findings, and results of meta–analyses have been published that compare non–identical probiotic strains, making the evidence difficult to interpret. A transparent and rigorous methodology is needed when evaluating the evidence because this topic remains complex.

Lower GI symptoms commonly require a visit to a physician, but the heterogeneity of symptoms presented and their underlying causes may limit the pharmacological treatment options offered because no single dominant drug therapy would be effective in all cases. Although new pharmacological treatments are emerging, challenges remain in terms of their ability to improve symptoms without incurring side effects.[18–21] Current evidence suggests that probiotics in the diet may play a role in reducing uncomfortable lower GI symptoms in adults. Therefore, as before, the emphasis of the ESPCG updated evidence–based guidelines is on the potential role of probiotics in the management of lower GI symptoms in clinical practice.