Skip to main content
OpenTrials
Completed

NCT Number: NCT06676488

A Randomized Crossover Trial of Bright Light Therapy in Irritable Bowel Syndrome

The purpose of this research study is to assess whether morning bright light therapy (BLT) using a wearable device called a Re-Timer could potentially improve Irritable Bowel Syndrome (IBS) symptoms and decrease intestinal permeability (leaky gut). Morning bright light therapy will be administrated through a safe-wearable glasses device called a Re-Timer. The Re-Timer glasses are lightweight and deliver blue-green light at 500nm, mimicking exposure to natural light.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Irritable Bowel Syndrome (IBS) Circadian Misalignment Colonic Diseases Colonic Diseases, Functional Digestive System Diseases Gastrointestinal Diseases Intestinal Diseases Irritable Bowel Syndrome

Age range

18 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Medical University of South Carolina

Charleston, South Carolina, 29425, United States

About this study

The hypothesis of this study is that morning bright light therapy (BLT) using Re-Timer™ glasses in irritable bowel syndrome (IBS) patients with circadian misalignment (CM), will improve IBS symptom severity, improve circadian misalignment, decrease intestinal permeability and improve stool microbial diversity. Our overall objective is to assess the effects of morning bright light therapy on IBS symptom severity, circadian misalignment, intestinal permeability and intestinal microbiota. We propose to conduct a 6-week, single center, randomized, crossover pilot trial involving 30 subjects with active IBS symptoms (IBS-SSS >75), and circadian misalignment (CM) based on late chronotype (Munich Chronotype Questionnaire, Corrected Midpoint of Sleep > 4:00h). Subjects will be randomized to BLT or placebo with a 2-week washout between each condition. All subjects will have assessments at two timepoints: after 2 weeks of BLT, and after 2 weeks of placebo.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • 18-65 years old
  • Irritable Bowel Syndrome based on Rome IV diagnostic criteria
  • Mild to severe IBS symptom severity based on IBS-SSS greater than or equal to 75 17.
  • Late chronotype based on the Munich Chronotype Questionnaire (Corrected Midpoint of Sleep > 4:00h) 18 Exclusion Criteria
  • Subject that are pregnant or plan to become pregnant.
  • Night shift workers or people who have crossed more than 2 time zones in the previous 4 weeks.
  • Regular use of medications that affect intestinal permeability, and/or endogenous melatonin including metoclopramide, NSAIDs, beta blockers, antibiotics, psychotropic medications, hypnotics and exogenous melatonin products during 4 weeks prior to the study.
  • Any major organ disease - known renal impairment, diabetes, liver disease, or significant cardiac failure (NY classification stage III/IV), inflammatory bowel disease or celiac disease per chart review and/or medical history.
  • Diagnosis of narrow angle glaucoma or retinal disorders or demonstrated symptoms indicative of these diagnosis during the eligibility screening.
  • Moderate to severe depression (score ≥ 21 or any endorsement of suicidal intent on the Beck Depression Inventory) 19
  • Sleep apnea (score high risk in 2 or more categories of the Berlin Questionnaire) 20
  • Restless leg syndrome (score ≥ 15 on the IRLS Study Group Rating Scale) 21
  • Inability or unwillingness of subject to sign an informed consent

Treatment and study plan

Re-Timer glasses

Device

Morning bright light therapy (BLT) will be administered through a safe wearable glasses device called a Re-Timer, purchased from the manufacturer Re-Timer.

Placebo Device

Device

Placebo glasses not providing Bright Light Therapy

Primary outcomes

  1. Aim 1a

    Time frame: 2 weeks of morning Bright Light Therapy (BLT)

    In Aim 1a, we predict 2 weeks of morning BLT in IBS subjects with CM will improve IBS-symptom severity based on the IBS Severity Scoring Scale as compared to the control (wear the Re-Timer™ glasses without light therapy).

  2. Aim 1b

    Time frame: 2 weeks of morning Bright Light Therapy (BLT)

    In Aim 1b, we predict 2 weeks of morning BLT will improve circadian misalignment as accessed by wrist actigraphy (interdaily stability, intradaily variability, and relative amplitude).

Secondary outcomes

  1. Aim 2

    Time frame: 2 weeks of morning Bright Light Therapy (BLT)

    Aim 2, we will evaluate the impact of BLT on intestinal barrier homeostasis in IBS as measured by 2a) intestinal permeability, urinary sucralose percent excretion after oral challenge and 2b) stool microbiota diversity using 16S ribosomal RNA sequencing. We predict that BLT will decrease intestinal permeability and improve stool microbiota diversity and structure.

Sponsors and collaborators

Lead sponsor

Medical University of South Carolina

Other

Collaborators

  • National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Registry information

Important dates

Study start
2025
Primary completion
2026
Study completion
2026
First posted
Nov 6, 2024
Registry last updated
Apr 7, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.