A Double-blinded,Double-dummy Clinical Trial of Chinese Herbal Medicine (MaZiRenWan) for Functional Constipation

Chinese Herbal Medicine (MaZhiRenWan) for Functional Constipation: a Prospective, Double-blinded, Double-dummy, Randomized Controlled Study

The objective of this study is to evaluate the efficacy and safety of a Chinese herbal proprietary medicine, MaZiRenWan (MZRW), by comparing with stimulant laxative western medicine (WM), senna, and placebo for patients with functional constipation (FC) in excessive TCM syndrome.

Functional constipation (FC) is a common clinical complaint. Despite the effectiveness of MaZiRenWan (MZRW) for alleviating FC symptoms has been proofed in the previous study.Given the results of the dose determination study and placebo-controlled study of MZRW, we hypothesize that MZRW is more useful than senna (senokot), a commonly used WM drug for constipation, for FC patients in excessive TCM syndrome.This is a prospective, double-blind, double dummy, randomized, controlled trial. After a 2-week run-in, eligible FC patients (Rome III) in excessive TCM syndrome will randomly be assigned to CHM arm (MZRW and WM placebo), WM arm (senna and CHM placebo) or placebo arm (CHM placebo and WM placebo). Patients will undergo an 8-week treatment and an 8-week follow-up.

Inclusion Criteria:

• either gender aged 18 to 65 years
• have FC diagnosed as Rome III criterial
• have diagnosis of Excessive Constipation according to the TCM theory
• complete spontaneous bowel movement (CSBM) ≦2times/w
• severity of constipation≧3pts (7 pts scale from 0 to 6pts) and the overall scoring of constipation-related symptoms≧6pts (6items in 7pts scale) for self symptom assessment in the run-in period
• normal colonic evaluation (colonoscopy or barium enema) within 12 months
• normal liver and renal function in blood test within 3 months

Exclusion Criteria:

• drug-induced constipation
• secondary causes of constipation (i.e. medical history of diabetes mellitus and thyroid disease)
• abdominal surgery (i.e. Caesarean operation)
• severe diseases (i.e. cancer and acute present asthma)
• allergy to CHM (i.e. G6PD deficiency), senna and tartrazine
• pregnancy or breast-feeding
• psychiatric or addictive disorders