Chinese Herbal Medicine Falls Short for Irritable Bowel Syndrome By Jeff Minerd , MedPage Today Staff WriterReviewed by Robert Jasmer, MD; Assistant Professor of Medicine, University of California, San Francisco MedPage Today Action Points
- Advise patients that this review does not support use of traditional Chinese herbal medicine for irritable bowel syndrome because of the low quality of most of the studies done to date.
- Advise patients that rigorously conducted, randomized, double-blinded, and placebo-controlled trials must prove the safety and efficacy of traditional Chinese herbal medicine for irritable bowel syndrome before such an approach can be recommended.
ReviewBEIJING, Jan. 25 - Although some traditional Chinese herbal medicines may help patients with irritable bowel syndrome, the evidence of efficacy is woefully inadequate, according to a systematic review by the Cochrane Collaboration. Of 75 randomized trials reviewed, only three were judged to be of high quality, while the rigor of the remaining trials was "generally low," said Jianping Liu, M.D., Ph.D., of the Beijing University of Chinese Medicine here and colleagues. Of the three high-quality trials-conducted in Germany, Israel, and Australia-two yielded positive findings and one was mixed, Dr. Liu and colleagues reported online today in the Cochrane Database of Systematic Reviews. The review was partially funded by the U.S. National Institutes of Health. The German study found that two herbal preparations, designated STW 5 and STW 5-II, showed significant symptom improvement as rated by a gastroenterologist compared with placebo. For STW 5, relative risk=1.68; 95% confidence interval=1.00-2.84. For STW 5-II, RR=1.90; 95% CI=1.15-3.14. The Israeli study found that the Tibetan herbal formula known as Padma Lax significantly improved symptoms of constipation-predominant IBS compared with placebo, as rated by patients (RR=6.35; 95% CI=1.52-26.57). The Australian study found that a standard Chinese herbal formulation significantly improved IBS symptoms compared with placebo, as rated by patients (RR=2.15; 95% CI=1.07-4.32) and by a gastroenterologist (RR=2.62; 95% CI=1.19-5.77). But the study found no improvement associated with individualized herbal preparations. (In China, standard formulations are often individualized according to a patient's particular symptoms, the review authors noted.) The 75 trials-identified by searches of international, U.S., and Chinese medical literature databases-tested 71 different types of Chinese herbal medicines. Seventy of the trials were conducted in China and published in Chinese. The trials involved nearly 8,000 men and women with an average age of 40. The trials were generally small, ranging from 45 to 453 patients, with an average size of 105 patients. One key reason that the Chinese trials were judged of low methodological quality is that placebo-controlled trials are uncommon in China, where most researchers believe they are unethical. Instead, the medicine to be investigated is compared with standard treatments, similar to cancer trials in the U.S., but the efficacy of the standard treatments is often not well-established, the review authors said. In addition, many of the trials suffered from problems with randomization and blinding techniques as well as lack of information on how the herbal medicines were prepared and what they contained, the authors said. "In this review, many of the trials show symptomatic benefit of herbal medicines in patients with IBS either compared with placebo or with conventional therapy," the authors said. "However, there is a lack of replicable evidence because no more than one trial compared the same herbal medicine and control treatment," they added. "Thus, the benefit of herbal treatment may not be conclusive." Because of the small sample sizes and general low quality of the studies, the authors concluded that "the benefit evidence from this review is not convincing enough to warrant a clinical recommendation." The study was supported in part by the National Center for Complementary and Alternative Medicine, a component of the U.S. National Institutes of Health. Primary source: The Cochrane Database of Systematic ReviewsSource reference: Liu JP et al. Herbal medicines for treatment of irritable bowel syndrome (review). The Cochrane Database of Systematic Reviews. January 25, 2006. --------------------------------------------------------------------------------Disclaimer The information presented in this activity is that of the authors and does not necessarily represent the views of the University of Pennsylvania School of Medicine, MedPage Today, and the commercial supporter. Specific medicines discussed in this activity may not yet be approved by the FDA for the use as indicated by the writer or reviewer. Before prescribing any medication, we advise you to review the complete prescribing information, including indications, contraindications, warnings, precautions, and adverse effects. Specific patient care decisions are the responsibility of the healthcare professional caring for the patient. Please review our Terms of Use. © 2004-5 MedPage Today, LLC. All Rights Reserved.
