A study testing whether a traditional herbal medicine can improve constipation and gut health in people with irritable bowel syndrome
| ISRCTN | ISRCTN59688916 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN59688916 |
| Sponsor | Taixing People's Hospital |
| Funder | Investigator initiated and funded |
- Submission date
- 19/03/2026
- Registration date
- 28/03/2026
- Last edited
- 20/03/2026
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Digestive System
Plain English summary of protocol
Background and study aims
Irritable bowel syndrome is a common condition that affects the digestive system and can cause symptoms such as constipation, abdominal pain, and bloating. Current treatments do not work well for everyone. There is growing interest in whether traditional herbal medicines can improve symptoms by affecting gut health and the bacteria living in the intestines. This study aims to find out whether a herbal medicine called Zhishi Daozhi Pill can improve bowel habits and overall symptoms in people with constipation-predominant irritable bowel syndrome.
Who can participate?
Adults aged 18 to 65 years with constipation-predominant irritable bowel syndrome.
What does the study involve?
Participants are randomly assigned to receive either the herbal medicine or a placebo (a look-alike inactive treatment). Neither the participants nor the researchers know which treatment each person receives during the study. The treatment is taken by mouth twice daily for 12 weeks. Participants record their bowel habits and symptoms, attend regular study visits, and provide stool samples for analysis.
What are the possible benefits and risks of participating?
Participants may experience improvement in their symptoms, but this cannot be guaranteed. The herbal medicine has been used traditionally and is expected to be safe, but mild side effects such as digestive discomfort may occur. There is also a small inconvenience related to study visits and sample collection.
Where is the study run from?
The Taixing People’s Hospital in Jiangsu Province, China.
When is the study starting and how long is it expected to run for?
October 2025 to February 2026.
Who is funding the study?
Investigator initiated and funded.
Who is the main contact?
Dr Shaohua Luo at Taixing People’s Hospital (email available upon request).
Contact information
Principal investigator, Public
Department of Traditional Chinese Medicine, Taixing People’s Hospital, No. 1 Changzheng Road
Taixing
225400
China
| Phone | +8615195272322 |
|---|---|
| xngbbamm@163.com |
Scientific, Principal investigator
Department of Gastroenterology, Taixing People’s Hospital, No. 1 Changzheng Road
Taixing
225400
China
| Phone | +8615195272322 |
|---|---|
| cl_1123@163.com |
Study information
| Primary study design | Interventional |
|---|---|
| Allocation | Randomized controlled trial |
| Masking | Blinded (masking used) |
| Control | Placebo |
| Assignment | Parallel |
| Purpose | Treatment |
| Scientific title | Adults with constipation-predominant irritable bowel syndrome receiving Zhishi Daozhi Pill compared with placebo for improving bowel movements and symptom severity in a randomized double-blind controlled trial |
| Study acronym | ZDP-IBS |
| Study objectives | The primary objective of this study is to evaluate whether Zhishi Daozhi Pill improves bowel function and overall symptom severity in adults with constipation-predominant irritable bowel syndrome compared with placebo. Secondary objectives are to assess the effects of the intervention on stool consistency, abdominal symptoms, quality of life, and safety. Exploratory objectives are to investigate whether clinical improvements are associated with changes in gut microbiota composition and metabolite profiles, including short-chain fatty acids, bile acids, and neuroactive compounds. |
| Ethics approval(s) |
Approved 30/09/2025, Medical Ethics Committee of Taixing People’s Hospital (No. 1 Changzheng Road, Taixing City, Jiangsu Province; No. 98 Runtai South Road, Taixing City, Taixing, 225400, China; +8652387656024; kjk6024@163.com), ref: LS2025062 |
| Health condition(s) or problem(s) studied | Treatment of constipation-predominant irritable bowel syndrome in adults |
| Intervention | Participants are randomised in a 1:1 ratio to receive either Zhishi Daozhi Pill or a matched placebo using a computer-generated randomisation schedule with allocation concealment. The intervention group receives Zhishi Daozhi Pill capsules containing standardised herbal extracts, administered orally at a dose of 6 g twice daily for 12 weeks. The control group receives identical placebo capsules administered at the same frequency and duration. Both participants and study personnel are blinded to treatment allocation throughout the study period. Concomitant use of stable fibre supplements is permitted, while initiation of probiotics, prebiotics, antibiotics, or prescription laxatives is prohibited. Rescue medication with polyethylene glycol is allowed in limited amounts and is recorded. |
| Intervention type | Supplement |
| Primary outcome measure(s) |
|
| Key secondary outcome measure(s) |
|
| Completion date | 28/02/2026 |
Eligibility
| Participant type(s) | |
|---|---|
| Age group | Mixed |
| Lower age limit | 18 Years |
| Upper age limit | 65 Years |
| Sex | All |
| Target sample size at registration | 120 |
| Total final enrolment | 120 |
| Key inclusion criteria | 1. Adults aged 18 to 65 years. 2. Diagnosis of constipation-predominant irritable bowel syndrome according to Rome IV criteria. 3. Irritable Bowel Syndrome Severity Scoring System score of 175 or higher at screening. 4. Fewer than 3 complete spontaneous bowel movements per week during the 2-week run-in period. 5. Ability and willingness to provide written informed consent. |
| Key exclusion criteria | 1. Presence of organic gastrointestinal disease such as inflammatory bowel disease or colorectal cancer. 2. History of gastrointestinal surgery affecting bowel motility. 3. Major psychiatric illness. 4. Pregnancy or breastfeeding. 5. Use of antibiotics, probiotics, prebiotics, or laxatives within 4 weeks prior to enrolment. 6. Participation in another interventional clinical trial. 7. Clinically significant comorbid conditions that could interfere with study participation. |
| Date of first enrolment | 01/10/2025 |
| Date of final enrolment | 15/12/2025 |
Locations
Countries of recruitment
- China
Study participating centres
Results and Publications
| Individual participant data (IPD) Intention to share | No |
|---|---|
| IPD sharing plan |
Editorial Notes
20/03/2026: Study’s existence confirmed by the Medical Ethics Committee of Taixing People’s Hospital, China.
