Effects of acute hydroxy gas inhalation on exercise-induced bronchoconstriction

The effects of acute hydroxy gas inhalation on lung function and inflammatory markers in individuals with mild to moderate asthma and exercise-induced bronchoconstriction (EIB)

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

ISRCTN

Registry ID

ISRCTN11644788

Enrollment

Registered

2023-10-24

Start date

2022-01-03

Completion date

Unknown

Last updated

2026-07-20

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Exercise-induced bronchoconstriction Respiratory

Interventions

There are 4 study visits. Each participant will inhale either hydroxy gas (2-3% hydrogen gas) or placebo gas (control condition) for 60 minutes using a nasal cannula before a bronchoprovocation test

Eligibility

Sex/Gender

All

Age

18 Years to 50 Years

Inclusion criteria

Inclusion criteria: 1. Ability to consent to the research 2. Aged 18 to 50 years old 3. Current clinical-based diagnosis of exercise-induced bronchoconstriction 4. Normal resting forced expiratory volume in one second (FEV1) defined as greater than 80% predicted value

Exclusion criteria

Exclusion criteria: 1. Chest infection within the past 4 weeks or hospitalisation 2. Baseline FEV1 <80% predicted value 3. Any other respiratory condition (other than asthma) 4. Any other chronic medical conditions (e.g., cardiovascular, neurological and metabolic)

Design outcomes

Primary

Measure	Time frame
1. Eucapnic Voluntary Hyperpnoea (EVH) challenge with lung function measures taken in triplicate before and in duplicate at 3, 5, 7, 10 and 15 minutes post EVH challenge. 2. Urinary 9a,11ß-prostaglandin and Clara cell protein (CC16) levels measured using enzyme-linked immunosorbent assay (ELISA) of samples collected before and after (~1 h) EVH challenge 3. Blood hydroxyl radical levels measured using a blood test in samples before and after (~1 h) EVH challenge	—

Measure

Time frame

1. Eucapnic Voluntary Hyperpnoea (EVH) challenge with lung function measures taken in triplicate before and in duplicate at 3, 5, 7, 10 and 15 minutes post EVH challenge. 2. Urinary 9a,11ß-prostaglandin and Clara cell protein (CC16) levels measured using enzyme-linked immunosorbent assay (ELISA) of samples collected before and after (~1 h) EVH challenge 3. Blood hydroxyl radical levels measured using a blood test in samples before and after (~1 h) EVH challenge

—

Secondary

Measure	Time frame
Difficulty breathing measured using the revised Borg Rating of Perceived Exertion (RPE) scale at baseline and immediately following the EVH challenge	—

Countries

England, United Kingdom

Contacts

Public ContactSavannah Sturridge

Savannah.Sturridge@brunel.ac.ukNone available

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Jul 23, 2026