Effects of Herbal Medicines in Patients with Irritable Bowel Syndrome

Abstract

Irritable bowel syndrome (IBS) is a common gastrointestinal(GI) disorder associated with alterations in motility, secretion and visceral sensation. Pharmacologic agents used to treat IBS include antispasmodics, 5-hydroxytryptamine-3 receptor (5-HT3) antagonists, 5-hydroxytryptamine-4 (5-HT4) agonists, antibiotics, probiotics, antidepressants and herbal medicines. No single therapy is reliably effective, and an increasing number of patients are taking herbal medicines worldwide. This review describes the effectiveness of herbal medicines in patients with IBS. Of single preparations, peppermint oil has shown the most evidence for efficacy, whereas, of compound preparations, most randomized controlled trials (RCTs) have been performed with TongXieYaoFang (TXYF). Daikenchuto (DKT) appears to be safe and well tolerated, and RCTs of DKT for functional constipation and IBS are now ongoing or being planned. No serious adverse events have been reported, but this may be due to publication bias or the lack of proper monitoring. Although herbal medicines may have therapeutic benefit in patients with IBS, further studies are needed to determine their efficacy and safety.