Effect of Ramosetron in Patients With Diarrhea Predominant Irritable Bowel Syndrome

Effect of Ramosetron in Patients With Diarrhea Predominant Irritable Bowel Syndrome: A Randomized, Double-Blind, Placebo-Controlled Study

Irritable bowel syndrome (IBS) tends to be a lifelong disorder and it is often frustrating to both patients and physicians. This study aim of improving symptom control, reducing healthcare burden and upgrading the quality of life of patient with diarrhea predominant IBS-D.

Patients of both sex of age group 18-65 years attending gastroenterology outpatient department Dhaka Medical College Hospital (DMCH) meeting the inclusion criteria of Diarrhea predominant irritable bowel syndrome (IBS-D) will be initially enrolled for the study. Their history, clinical examination & initial investigations will be done. Report will be noted in the standard data sheet. Any alternative diagnosis if proven by clinical examination or laboratory investigation will be excluded from the study.

Each patient will go through a run-in period of 7 days. Number of subjects will be recruited according to sample size. Randomization into two groups will be performed by online randomizer websites.

One group will receive tablet ramosetron 2.5 mcg one time daily at morning before breakfast while the other group will receive identical looking placebo one tablet once daily at same time. Both groups will be adviced for low FODMAP diet along with lifestyle modification. The tablets will be administered for total 4 weeks. Before starting treatment, each individual will undergo a baseline assessment during which demographic data, base line investigations, IBS symptoms by IBS Symptom Severity Score (IBS-SSS) will be recorded. Patients will be followed-up after 4 weeks and 8 weeks by IBS-SSS questionnaire. Any adverse effect will be reported quickly and documented at the same time.

IBS-SSS is a 5 item tools. It is primarily measures the IBS symptoms which includes abdominal pain and distension as well as bowel satisfaction. This scale evaluates IBS symptoms: abdominal pain, abdominal distension, stool frequency and consistency and interference with life in general. The IBS-SSS calculates the sum of these 5 items scored on a visual analogue scale from 0-100.

Study Overview

• Status: Not yet recruiting
• Conditions: IBS-D (Diarrhea-predominant)
• Intervention / Treatment: Drug: Ramosetron 2.5 microgram; Drug: Placebo

• Study Type: Interventional
• Enrollment (Estimated): 76
• Phase: Phase 4

Contacts and Locations

• Study Contact: Name: Dr. Md. Aminul Islam; Phone Number: +8801626299434; Email: aminulthesis0950@gmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adults aged 18-65 years.
• Patients fulfilling Rome IV diagnostic criteria for IBS-D.
• Willing to provide informed written consent.
• Patients able to attend regular follow-up visits during the study period.

Exclusion Criteria:

• Presence of alarm features: anemia, weight loss, per rectal bleeding, nocturnal frequency, and family history of colonic cancer or inflammatory bowel disease
• History of major gastrointestinal surgery (excluding appendicitis )
• Recent antibiotic use within 4 weeks
• Patient with uncontrolled diabetes, hyperthyroidism, hypothyroidism
• Pregnant or lactating women
• Drug abuse or alcohol abuse

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Ramosetron 2.5 microgram; Group A - Ramosetron 2.5 microgram	Drug: Ramosetron 2.5 microgram; Ramosetron 2.5 microgram will be given in Group A
Placebo Comparator: Placebo; Group B - Placebo	Drug: Placebo; Placebo will be given in Group C

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Improvement of diarrhea predominant IBS symptoms	The improvement of IBS symptoms will be assessed by IBS symptom severity score (IBS-SSS). This score is a Likert scale with seven domains divided into two parts. Part one is the severity score containing four domains, where domain one has two separate scoring scale. Each scale scoring from 0 to 100, that makes it a total score of 500. The severity is denoted as Mild (Score 75 to 175), Moderate (Score 176 to 300), and severe (Score more than 300). The part two is a descriptive questionnaire about bowel habit	At baseline before randomization and then at week 4 and week 8

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The effect of ramosetron in diarrhea predominant IBS patients	The improvement of IBS symptoms will be assessed by IBS symptom severity score (IBS-SSS). This score is a Likert scale with seven domains divided into two parts. Part one is the severity score containing four domains, where domain one has two separate scoring scale. Each scale scoring from 0 to 100, that makes it a total score of 500. The severity is denoted as Mild (Score 75 to 175), Moderate (Score 176 to 300), and severe (Score more than 300). The part two is a descriptive questionnaire about bowel habit.	At baseline before randomization and then at week 4 and week 8
The effect of placebo in diarrhea predominant IBS patients	The improvement of IBS symptoms will be assessed by IBS symptom severity score (IBS-SSS). This score is a Likert scale with seven domains divided into two parts. Part one is the severity score containing four domains, where domain one has two separate scoring scale. Each scale scoring from 0 to 100, that makes it a total score of 500. The severity is denoted as Mild (Score 75 to 175), Moderate (Score 176 to 300), and severe (Score more than 300). The part two is a descriptive questionnaire about bowel habit.	At baseline before randomization and then at week 4 and week 8
Compare the effect of ramosetron and placebo	The improvement of IBS symptoms will be assessed by IBS symptom severity score (IBS-SSS). This score is a Likert scale with seven domains divided into two parts. Part one is the severity score containing four domains, where domain one has two separate scoring scale. Each scale scoring from 0 to 100, that makes it a total score of 500. The severity is denoted as Mild (Score 75 to 175), Moderate (Score 176 to 300), and severe (Score more than 300). The part two is a descriptive questionnaire about bowel habit.	At baseline before randomization and then at week 4 and week 8
Adverse events	Patient reported adverse events will be documented	through study completion, approximately 1 year

Collaborators and Investigators

• Sponsor: Md. Aminul Islam

Study record dates

Study Major Dates

• Study Start (Estimated): April 30, 2026
• Primary Completion (Estimated): January 1, 2027
• Study Completion (Estimated): February 1, 2027

Study Registration Dates

• First Submitted: April 22, 2026
• First Submitted That Met QC Criteria: May 4, 2026
• First Posted (Actual): May 7, 2026

Study Record Updates

• Last Update Posted (Actual): May 7, 2026
• Last Update Submitted That Met QC Criteria: May 4, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Ramosetron; IBS-D; IBS-SSS; Diarrhea Predominant Irritable Bowel Syndrome
• Other Study ID Numbers: IRB-DMC/2025/259

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No