Complementary and alternative medicine includes a wide range of practices and therapies outside the realms of conventional western medicine. Despite a lack of scientific data in the form of controlled trials for either efficacy or safety of complementary and alternative medicine, use by patients with inflammatory bowel disease, particularly of herbal therapies, is widespread and increasing. There is limited controlled evidence indicating efficacy of traditional Chinese medicines, aloe vera gel, wheat grass juice, Boswellia serrata and bovine colostrum enemas in ulcerative colitis. Encouraging results have also been reported in small studies of acupuncture for Crohn's disease and ulcerative colitis. Contrary to popular belief, natural therapies are not necessarily safe: fatal hepatic and irreversible renal failure have occurred with some preparations and interactions with conventional drugs are potentially dangerous. There is a need for further controlled clinical trials of the potential efficacy of complementary and alternative approaches in inflammatory bowel disease, together with enhanced legislation to maximize their quality and safety.