In evaluating the effectiveness and safety of peppermint oil for irritable bowel syndrome, the researchers searched medical literature for randomised controlled trials involving peppermint oil treatments in IBS. A systematic review and analysis included trials up to the date of April 2nd, 2022. The team assessed the efficacy and safety of the peppermint oil treatment based on various factors including effect on global IBS symptoms and abdominal pain along with incidence of adverse events or gastro-oesophageal reflux.

From the literature review, 10 suitable randomised control trials were identified, encompassing a total of 1030 patients. The results showed that peppermint oil performed better than a placebo in lessening overall irritable bowel syndrome symptoms and reducing abdominal pain. However, this was coupled with a higher rate of recorded adverse events in patients who were administered peppermint oil. Despite the positive performance of peppermint oil over placebo, the evidence quality considered for this conclusion was very low.