Enteric-Coated Peppermint Oil Versus Standard Antispasmodic in SLC6A4 (5-HTTLPR) Carriers With Irritable Bowel Syndrome.

NCT06914921 | Completed

• 1 other identifier: SW027
• Study Type: interventional
• Target: 224
• Locations: 1 country
• Sites: 1

Brief Summary

This study is a non-inferiority, double-blind, randomized controlled trial comparing enteric-coated peppermint oil with a standard antispasmodic (e.g., mebeverine) in adult IBS patients who carry at least one "S" allele in the SLC6A4 (5-HTTLPR) polymorphism. The primary goal is to see whether peppermint oil provides symptom relief (measured by IBS severity scores) that is not worse than the antispasmodic by more than a predefined margin (30 points on the IBS-SSS). Secondary goals include evaluating differences in abdominal pain, stool patterns, quality of life, and adverse event profiles, with a focus on peppermint oil's tolerability. About 224 participants (112 per arm) will be enrolled, with allowances for dropout, to detect non-inferiority at 80% power. After 12 weeks of treatment, results will inform whether peppermint oil is a viable, well-tolerated alternative to standard antispasmodics, especially in patients with heightened GI sensitivity linked to the SLC6A4 polymorphism.

Conditions

Irritable Bowel Syndrome (IBS)

Keywords

supplements; genetics; peppermint oil

Outcome Measures

Primary Outcomes (1)

• Irritable Bowel Syndrome

  Symptom severity in this trial is captured with the IBS-SSS (IBS Severity Scoring System): 0 = no symptoms to 500 = most severe symptoms

  12 weeks

Secondary Outcomes (7)

• Numeric Rating Scale (for abdominal pain)

  12 weeks

• Abdominal Pain: Measured by visual analog score

  12 weeks

• Stool Consistency: Bristol Stool Form Scale

  12 weeks

• Quality of Life: Irritable Bowel Syndrome Quality of Life Questionnaire

  12 weeks

• Quality of Life: 36-Item Short Form Health Survey

  12 weeks

Study Arms (2)

Enteric-coated peppermint oil capsules (~180 mg total peppermint oil/ capsule) to ensure release in

EXPERIMENTAL

Dietary Supplement: Peppermint Oil

A standard antispasmodiс

ACTIVE COMPARATOR

A standard antispasmodic (e.g., mebeverine 135 mg).

Drug: A standard antispasmodic

Interventions

Peppermint Oil DIETARY_SUPPLEMENT

Enteric-coated peppermint oil capsules (\~180 mg total peppermint oil/ capsule) to ensure release in the small intestine. 1 capsule three times daily, 30 minutes before meals, for 12 weeks.

Enteric-coated peppermint oil capsules (~180 mg total peppermint oil/ capsule) to ensure release in

A standard antispasmodic DRUG

A standard antispasmodic (e.g., mebeverine 135 mg). 1 tablet three times daily, before meals, for 12 weeks.

A standard antispasmodiс

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults aged 18-65 years.
• Diagnosis of Irritable Bowel Syndrome by Rome IV criteria, with at least moderate severity (IBS-SSS ≥ 175).
• SLC6A4 genotyping confirms at least one S allele (SS or SL).
• Able and willing to provide informed consent and comply with study procedures.

You may not qualify if:

• L/L genotype of 5-HTTLPR.
• Known organic GI diseases (e.g., IBD, celiac disease).
• Severe/unstable comorbidities (e.g., cardiac, hepatic, or renal dysfunction).
• Use of peppermint oil, antispasmodics, or investigational drugs within 30 days prior to enrollment.
• Known hypersensitivity to peppermint or mebeverine.
• Pregnancy or breastfeeding.
• Significant psychiatric illness that, in the investigator's judgment, might interfere with participation.

Sponsors & Collaborators

• S.LAB (SOLOWAYS): lead
• Center for New Medical Technologies, Novosibirsk, Russia: collaborator

Study Sites (1)

Center for New Medical Technologirs

Novosibirsk, 630090, Russia

Location

MeSH Terms

Conditions

Irritable Bowel Syndrome

Interventions

peppermint oil

Condition Hierarchy (Ancestors)

Colonic Diseases, Functional; Colonic Diseases; Intestinal Diseases; Gastrointestinal Diseases; Digestive System Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 4, 2025
• First Posted: April 7, 2025
• Study Start: February 4, 2024
• Primary Completion: January 17, 2025
• Study Completion: February 1, 2025
• Last Updated: April 23, 2025

Record last verified: 2025-04

Data Sharing

• IPD Sharing: Will not share

Locations

RU (1)