Tong-Xie-Yao-Fang Granules for Diarrhea-predominant Irritable Bowel Syndrome

Study Overview
=================
Brief Summary
-----------------
The purpose of this study is to test the efficacy and safety of a traditional Chinese medication Tong-Xie-Yao-Fang for patients with diarrhea-predominant irritable bowel Syndrome (IBS-D).

Detailed Description
-----------------
Participants: The sample size of this trial is 118, to test an odds ratio of 3.5 at a significance of 0.05 and power of 0.8. Intervention: Tong-Xie-Yao-Fang versus placebo Data collection: Standard operation procedure will be developed for how to interviewing the participants, how to use the IBS diary, how to enter the data into the electronic case report forms.

Official Title
-----------------
Traditional Chinese Medicine Tong-Xie-Yao-Fang Granules for Diarrhea-predominant Irritable Bowel Syndrome: a Randomized Placebo-controlled Trial and a Mechanistic Study

Conditions
-----------------
Diarrhea-predominant Irritable Bowel Syndrome

Intervention / Treatment
-----------------
* Drug: Tong-Xie-Yao-Fang
* Drug: Placebo


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Being diagnosed as IBS according to the Rome III criteria; Diarrhea was present for at least 75% of the time; With a TCM differentiation as liver stagnation and spleen defficiency Had a colonoscopy within a year to rule out other bowel diseases. Exclusion Criteria: Organic gastrointestinal disease, such as colorectal cancer, inflammatory bowel disease, advanced colonic polyp; Had gastrointestinal surgery within a year; Used durgs that affect gastrointestinal motility; Had psychological disorder; Serious disease in other system, which may bias the outcome measures.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Tong-Xie-Yao-Fang<br>Tong-Xie-Yao-Fang is a classic formula of traditional Chinese medicine for IBS-D. It is composed of 4 herbs: Radix Paeoniae Alba, Ledebouriella seseloides Wolff, pericarpium citri reticulatae and Rhizoma Atractylodis Macrocephalae. The granules will be administrated for thrice daily at a dose of 15g per time. The total duration of treatment is 4 weeks. | Drug: Tong-Xie-Yao-Fang<br>* Tong-Xie-Yao-Fang is a traditional Chinese formula. It is used for diarrhea management.<br>* Other names: Tongxieyaofang;|
| Placebo Comparator: Placebo<br>It is a placebo that made with similar appearance and taste as the Tong-Xie-Yao-Fang granules. | Drug: Placebo<br>* The placebo is the same as Tong-Xie-Yao-Fang in appearance.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the proportion of patients who had adequate relief of global IBS-D symptoms for at least 2 of the 4 weeks. |  | 4 weeks after initiation of treatment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Stool frequency per week |  | baseline(week 0), week 4, week 8, week 12 | 
| An visual scale rating the degree of IBS-D symptoms | The scale ranges from 0 to 10. The score 0 indicates the mildest degree, while the 10 indicates the most serious degree. | baseline(week 0), week 4, week 8, week 12 | 
| Proportion of adverse events |  | week 4 |