Chinese herbal medicine was effective in the irritable bowel syndrome
ACP J Club. 1999 May-June;130:74. doi:10.7326/ACPJC-1999-130-3-074
Bensoussan A, Talley NJ, Hing M, et al. Treatment of irritable bowel syndrome with Chinese herbal medicine: a randomized controlled trial. JAMA. 1998 Nov 11;280:1585-9.
In patients with the irritable bowel syndrome (IBS), is Chinese herbal medicine (CHM) effective for relieving symptoms?
Randomized, double-blind, placebo-controlled trial with 16-week follow-up.
2 teaching hospitals and 5 gastroenterology practices in Sydney, Australia.
116 patients who were 18 to 75 years of age (mean age 47 y, 65% women) and had IBS according to the Rome criteria. Exclusion criteria were pregnancy, lactation, substance abuse, psychiatric illness, dementia, allergies to food additives, lactose intolerance, inflammatory bowel disease, liver disease, gastric and duodenal ulcers, gastrointestinal cancer, celiac disease, or diabetes mellitus. Patients who used anticholinergic drugs, lactulose, smooth muscle relaxants, or antidepressants were included if they showed symptoms of IBS and had used the medication for 3 months and if the effects of the medication were stable. Follow-up was 85% for patient ratings and 94% for gastroenterologist ratings of symptoms.
After a 2-week run-in period, patients were allocated to 1 of 3 groups: individualized formulations of CHM, which were derived from 81 Chinese herbs (n = 38); a standard formulation of CHM (n = 43); or matching placebo (n = 35) for 16 weeks. Patients received dried herbs or placebo in 5 capsules given 3 times/d.
Main outcome measures
Change in IBS symptoms (assessed by using the Bowel Symptom Scale [BSS], which consisted of visual analog scales).
Symptoms were more improved in the standard CHM group than in the placebo group when rated by patients (mean total BSS score 106 vs 150, P = 0.03). Patient-rated symptom improvement was greater in the individualized CHM group than in the placebo group (mean total BSS score 103 vs 150, P = 0.03). At the end of the trial, more patients in the CHM groups rated themselves as improved and were rated improved by gastroenterologists than those in the placebo group (Table).
In patients with the irritable bowel syndrome, Chinese herbal medicine was effective for relieving symptoms.
Source of funding: University of Western Sydney Macarthur.
For correspondence: Mr. A. Bensoussan, Research Unit for Complementary Medicine, Faculty of Health, University of Western Sydney Macarthur, P.O. Box 555, Campbelltown, New South Wales 2560, Australia. FAX 61-2-9773-0998.
Table. Standard Chinese herbal medicine (S-CHM), individualized Chinese herbal medicine (I-CHM), and placebo for the irritable bowel syndrome*
|Outcomes at 16 wk||S-CHM||I-CHM||Placebo||RBI (95% CI)||NNT (CI)|
|Patient-rated improvement||76%||33%||129% (43 to 296)||3 (2 to 5)|
|64%||33%||93% (13 to 243)||4 (2 to 18)|
|Gastroenterologist-rated improvement||78%||30%||161% (56 to 380)||3 (2 to 4)|
|50%||30%||67% (-11 to 225)||Not significant|
*Abbreviations defined in Glossary; RBI, NNT, and CI calculated from data in article.
Bensoussan and colleagues report a well-done trial that shows efficacy of CHM for the treatment of IBS. Twice as many patients who received CHM (compared with placebo) rated themselves as improved. This is potentially good news because no drug is clearly effective in treating IBS (1). The authors used validated diagnostic criteria to include patients and used validated outcome measures to assess efficacy.
Should we now recommend CHM to our patients with IBS? Currently, my answer is "no." First, a single study, although well done, should generally not change our practice. Although other trials of CHM exist, their quality is uncertain (2). Second, recommending CHM without specifying a preparation would not be sensible. 7000 medicinal plants exist in China (3). The preparation in this study used 20 plants. Third, any lack of regulatory oversight of CHM could lead to uncertain content of pills.
In summary, I agree with the authors' conclusion: ". . .our findings support the consideration of further investigation of Chinese herbal medicine as a treatment option for IBS." In addition, now is the time for regulatory guidance of alternative medicines. Many western medications come from plants, and CHM will surely contribute additional effective drugs. However, regulation is needed to promote both safety and efficacy.
Robert G. Badgett, MD
University of Texas Health Sciences CenterSan Antonio, Texas, USA