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THE SOUTH AFRICAN GASTROENTEROLOGY REVIEW 2022 | VOLUME 20 | ISSUE 1 | 20 population; making it one of the more common GI disorders. 3,4 In addition it is reported that as much as 30% of visits to gastroenterologists belong to patients showing IBS-related symptoms. 5 IBS patients have shown similar or worse health-related quality of life (HRQoL), compared to chronic diseases like diabetes mellitus. 3 As a functional gastrointestinal disease (FGID), IBS is said to represent a major part of the work load of primary care physicians and gastroenterologists, and is also one of the leading causes for referral to emergency care units, thus draining substantial amounts of healthcare resources. 6 IBS largely remains an unexplained disorder of the gut function, as multiple disease pathways can lead to identical clinical phenotypes. 7 These include impaired motility and sensitivity, increased permeability, changes in the gut microbiome, psychological distress and alterations in the brain-gut axis. 4,7 Food also seems to play a key role, as most IBS patients report onset or exacerbation of symptoms after meals. Food intolerance is in turn associated with reduced quality of life and higher symptom severity scores. 7 Conventional medical treatment is purely symptomatic, and includes treatment with antispasmodics and laxatives to treat constipation- related symptoms, as well as bulking agents in the case of diarrhoea. Severe cases of the disorder may require muscle relaxants, antidepressants and anxiolytics. 4,7 Cognitive behavioural therapy (CBT) as well as hypnotherapy have also been used as psychological interventions. However, these treatment options have shown limited efficacy, and many patients resort to complementary and alternative medicine (CAM), despite lack of evidence to support its use. These include dietary interventions and herbal preparations including peppermint oil and Aloe. 8 Aloe is a plant genus that belongs to the Asphodelaceae family. They are perennial succulents, and characterized by long and thick fleshy leaves that are lance-shaped, with spiny margins and a sharp apex. Although the genus originated in the dry and warm climates of Africa, Aloes are very adaptable and can be found worldwide. Aloe leaves produce a yellow latex, referred to as Aloe sap. The leaf pulp is composed of parenchyma cells that make up a gel. 9 The gel and sap are extracted from the leaf, and it is these substances that are often used as treatment. Previous research in rats suggests Aloe’s laxative and anti-inflammatory actions may have a beneficial effect in the treatment of constipation-predominant IBS, 10,11,41 and research conducted on humans suggests it may be effective in treatment of inflammatory bowel disease symptoms 10,11 . Clinical trials have also been carried out to assess the effectiveness of Aloe in treating IBS symptoms among humans, however the evidence of its effects is limited and contradictory. 12 To date, the effectiveness of Aloe in treating IBS symptoms in clinical trials has not been systematically studied. Therefore, the objective of this study is to summarize the existing evidence on the contribution of Aloe to improved health outcomes among patients diagnosed with IBS, and where possible, identify potential factors that may influence this response. 2.AIM AND OBJECTIVES 2.1.AIM To evaluate the effect of Aloe on symptoms associated with Irritable Bowel Syndrome (IBS) in adults. 2.2.OBJECTIVES To summarize the existing evidence on the contribution of Aloe to improved health outcomes among adult patients diagnosed with IBS and where possible, identify potential factors that may influence this response. Review Question Among adults diagnosed with irritable bowel syndrome, is the consumption of Aloe, compared with placebo, associated with improved health outcomes? 2. METHODS 2.1.Protocol and Registration This systematic review and meta-analysis protocol has been published in the PROSPERO International Prospective Register of systematic reviews, 20 registration number CRD42018082663. 2.2.Search strategy The authors searched the medical literature using Medline, Scopus, EBM reviews, Africa-wide, CINAHL, Web of Science, Mednar, Cochrane Library, clinicaltrials.gov, World Health Organization Library Information System (WHOLIS), Ebscohost and grey literature (Google Scholar) up to August 2018. Randomized controlled trials of adults (>18 years) diagnosed with IBS based on diagnostic criteria (Manning or Rome iterations) were considered. Participants were required to report either a global assessment of cure or improvement of symptoms after treatment. If studies induced constipation or other IBS-related symptoms through the use of drugs, such as opioids, then these studies were excluded from the analysis. In addition to randomized controlled trials (RCTs), non-randomised controlled trials, retrospective and prospective cohort studies, and controlled before- and-after (CBA) studies were also considered as eligible for inclusion in the study. A comprehensive search strategy was developed to search both published and unpublished articles. These included peer-reviewed journal articles, conference proceedings and grey literature (including unpublished, internal or non-reviewed papers and technical reports). The strategy included MeSH and free-text terms relating to IBS and Aloe literature. No language restrictions were applied. The lead reviewer evaluated the titles and abstracts of papers identified by the initial search for appropriateness to the study question. Potentially relevant papers were downloaded and reviewed in detail. Two reviewers independently assessed pre-selected articles using predesigned data extraction forms according to pre-defined eligibility criteria. Any disagreement between investigators was resolved by consensus. Table 1 details the search strategy used for PubMed. This strategy was adapted to suit individual databases using applicable vocabulary and syntax. 2.3.Types of interventions For this review, the term ‘Aloe’ was used to denote any species of Aloe either in its natural form or in any commercially-available forms, including those used in conjunction with other compounds. Aloe was included in its different forms as a therapeutic intervention to address symptoms related to IBS. These included patients who had received conventional medications in addition to Aloe, as well as those who were no longer taking any conventional medication and were seeking further treatment. RESEARCH