Irritable bowel syndrome (IBS) and chinese herbal medicine

Irritable bowel syndrome is a common functional bowel disorder and there has been a great  need for good effective treatments. Zelnorm is effective in constipation predominant IBS.

Chinese herbal medicine has been suggested as treatment for Irritable bowel Syndrome. Randomized controlled trials have yielded conflicting results. The main reason for the conflicting reasons may be due the differences in patient populations and the herbs studied. We will review two such studies here.

Bensoussan and colleagues from Australia published their findings in the prestigious Journal of American Medical association.  They conducted a double-blind  randomized placebo controlled trial. A total of 116 patients based on Rome criteria were recruited. They were divided into three groups.  Patients were randomly assigned to individualized Chinese herbal formulations, a standard Chinese herbal formulation, or placebo for 16 weeks.

The authors found that as compared to placebo, the patients in the active treatment groups (standard and individualized chinese herbs) had significant improvement in bowel symptom scores as rated by patients and by gastroenterologists. Similarly, there was significant global improvement as rated by patients and by gastroenterologists. There was a decrease in degree of interference with life caused by IBS symptoms as assessed by patients themselves. Chinese herbal formulations individually tailored to the patient was as effective as the standard treatment. However, at 14 weeks after completing the therapy, the effects were sustained only in the individualized treatment group.

A more recent study by Leung and colleagues from the Chinese University of Hongkong studied only patients with diarrhea predominant IBS. In their study titled, "Treatment of diarrhea-predominant irritable bowel syndrome with traditional Chinese herbal medicine: a randomized placebo-controlled trial" , they demonstrated that Chinese medicine does not have any benefit over placebo.

These investigators studied the effectiveness an ancient herbal Chinese formula in patients with diarrhea-predominant IBS. Patients were recruited based on the established Rome II criteria and confirmation by a herbalist. 119 Patients received a standard preparation of TCM extracts containing 11 herbs or a placebo for 8 weeks. Patients were followed for further 8 weeks after the treatment.

The authors found no significant difference in the proportion of patients with global symptom improvement between the Chinese medicine and placebo groups at week 8 as well as at week 16. There was also no difference in individual symptom and the quality-of-life scores between the two groups. The authors concluded that the use of this herbal formulation for diarrhea-predominant IBS did not lead to symptom improvement.