Herbal and plant therapy in patients with inflammatory bowel disease.

The use of herbal therapy in inflammatory bowel disease (IBD) is increasing worldwide. The aim of this study was to review the literature on the efficacy of herbal therapy in IBD patients. Studies on herbal therapy for IBD published in Medline and Embase were reviewed, and response to treatment and remission rates were recorded. Although the number of the relevant clinical studies is relatively small, it can be assumed that the efficacy of herbal therapies in IBD is promising. The most important clinical trials conducted so far refer to the use of mastic gum, tormentil extracts, wormwood herb, aloe vera, triticum aestivum, germinated barley foodstuff, and boswellia serrata. In ulcerative colitis, aloe vera gel, triticum aestivum, andrographis paniculata extract and topical Xilei-san were superior to placebo in inducing remission or clinical response, and curcumin was superior to placebo in maintaining remission; boswellia serrata gum resin and plantago ovata seeds were as effective as mesalazine, whereas oenothera biennis had similar relapse rates as ω-3 fatty acids in the treatment of ulcerative colitis. In Crohn's disease, mastic gum, Artemisia absinthium, and Tripterygium wilfordii were superior to placebo in inducing remission and preventing clinical postoperative recurrence, respectively. Herbal therapies exert their therapeutic benefit by different mechanisms including immune regulation, antioxidant activity, inhibition of leukotriene B4 and nuclear factor-kappa B, and antiplatelet activity. Large, double-blind clinical studies assessing the most commonly used natural substances should urgently be conducted.