Effect of Ipratropium Bromide on EILO

The Effect of Ipratropium Bromide on Exercise-Induced Laryngeal Obstruction (EILO) in Pediatric Patients

The investigators propose a study that compares breathlessness and airway obstruction during intense exercise in 34 children and adolescents with Exercise-Induced Laryngeal Obstruction after breathing in ipratropium bromide or placebo. It is hypothesized that breathlessness and airway obstruction will be lower following breathing in ipratropium bromide compared with placebo.

Study Overview

• Status: Not yet recruiting
• Conditions: Exercise-Induced Laryngeal Obstruction; Dyspnea During Activity
• Intervention / Treatment: Drug: Ipratropium Bromide; Drug: Normal Saline (Placebo)

Detailed Description

Many children and adolescents struggle with breathing problems during exercise. These symptoms can lead them to underperform, quit sports, and in some cases, stop being active altogether. One under-recognized cause is Exercise-Induced Laryngeal Obstruction (EILO), a narrowing of the airway at the level of the voice box. Approximately 5-8% of adolescents and 20-40% of adolescent athletes have EILO, an estimated 4-6 million nationwide. The most common treatment for EILO is Speech Therapy, with or without Physical Therapy. Where available, this requires significant time and financial commitment from patients and their families to attend therapy sessions and complete at-home exercises.

Case reports as early as 1985 have suggested aerosolized ipratropium bromide as an effective EILO treatment. One larger study could not confirm this observation. However, this study used an outcome measure with low reliability and validity, did not use a placebo control, and administered a low dose of ipratropium bromide too close to exercise.

The investigators propose a study that compares breathlessness and airway obstruction during intense exercise in 34 children and adolescents with EILO following inhalation of a higher dose of nebulized ipratropium bromide with placebo. It is hypothesized that breathlessness and airway obstruction will be lower following inhalation of ipratropium bromide compared with placebo.

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: John M Robertson, MD; Phone Number: 682-303-4200; Email: john.robertson@cookchildrens.org
• Study Contact Backup: Name: Andreas Kreutzer, PhD; Phone Number: 682-303-7576; Email: andy.kreutzer@cookchildrens.org

Study Locations

• United States
  • Texas
    • Prosper, Texas, United States, 75078
      • Cook Children's Pulmonology (Exercise Respiratory Center)
      • Contact: John M Robertson, MD; Phone Number: 682-303-4200; Email: john.robertson@cookchildrens.org
      • Contact: Andreas Kreutzer, PhD; Email: andy.kreutzer@cookchildrens.org
      • Principal Investigator: John M Robertson, MD
      • Sub-Investigator: Andreas Kreutzer, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients must be diagnosed with EILO confirmed by Continuous Laryngoscopy During Exercise
• Patients must be able to complete exercise testing
• Patients must report dyspnea
• Patients must have given assent with parental consent, understand all study procedures, and comply with them for the entire length of the study.

Exclusion Criteria:

• Patients that do not have EILO.
• Patients who did not undergo diagnostic CPET with CLE.
• Patients with hypersensitivity to atropine or its derivatives due to structural similarity with ipratropium bromide.
• Patients with a history of atrial flutter and/or fibrillation
• Patients taking anticholinergic medications that cannot be paused for 24 hours.
• Unable to perform exercise tests
• Current drug or alcohol use or dependence that, in the opinion of the site investigator, would interfere with adherence to study requirements.
• Inability or unwillingness of patient or parent/legally authorized representative to give written informed consent.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Ipratropium Bromide, then Placebo; Participants will receive Ipratropium Bromide in their first trial and Placebo in the second trial.	Drug: Ipratropium Bromide; Nebulized Ipratropium Bromide (500µg/2.5mL); one-time dose approximately 75 minutes before exercise, inhaled for 5-8 minutes; Drug: Normal Saline (Placebo); 3 mL of nebulized 0.9% normal saline; one-time dose approximately 75 minutes before exercise, inhaled for 5-8 minutes
Experimental: Placebo, then Ipratropium Bromide; Participants will receive Placebo in their first trial and Ipratropium Bromide in the second trial.	Drug: Ipratropium Bromide; Nebulized Ipratropium Bromide (500µg/2.5mL); one-time dose approximately 75 minutes before exercise, inhaled for 5-8 minutes; Drug: Normal Saline (Placebo); 3 mL of nebulized 0.9% normal saline; one-time dose approximately 75 minutes before exercise, inhaled for 5-8 minutes

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Visual Analogue Scale for Dyspnea (VAS-Dyspnea)	Shortness of breath assessed by a 0-100 Visual Analogue Scale for Dyspnea, where higher scores reflect greater breathlessness	Day1 and Day 2

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
CLE grade scoring	Patient videos will be assessed for laryngeal obstruction by two expert reviewers. Blinded reviewers will grade the severity of glottic and supraglottic obstruction on a scale from 0 (no obstruction) to 3 (severe obstruction).	Day 1 and Day 2

Collaborators and Investigators

• Sponsor: Cook Children's Health Care System

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): December 31, 2029
• Study Completion (Estimated): December 31, 2029

Study Registration Dates

• First Submitted: January 12, 2026
• First Submitted That Met QC Criteria: February 3, 2026
• First Posted (Actual): February 6, 2026

Study Record Updates

• Last Update Posted (Actual): May 5, 2026
• Last Update Submitted That Met QC Criteria: May 1, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Ipratropium Bromide; Exercise-Induced Laryngeal Obstruction; Shortness of Breath during Exercise
• Additional Relevant MeSH Terms: Organic Chemicals; Heterocyclic Compounds; Pharmaceutical Preparations; Alkaloids; Crystalloid Solutions; Isotonic Solutions; Solutions; Aza Compounds; Heterocyclic Compounds, Bridged-Ring; Atropine Derivatives; Tropanes; Azabicyclo Compounds; Belladonna Alkaloids; Solanaceous Alkaloids; Bridged Bicyclo Compounds, Heterocyclic; Ipratropium; Saline Solution
• Other Study ID Numbers: 2026-031

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: The investigators anticipate the institution's IRB/legal team will not approve sharing IPD.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No