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Citric acid cough challenge validation

Validation of the citric acid cough challenge using the KoKo DigiDoser system in healthy volunteers: a 4-week randomised single centre crossover study

Status
Active, not recruiting
Phases
Unknown
Study type
Interventional
Source
ISRCTN
Registry ID
ISRCTN98385033
Enrollment
30
Registered
2009-09-18
Start date
2006-07-04
Completion date
Unknown
Last updated
2015-01-13

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

Conditions

Artificially induced cough Signs and Symptoms Cough

Interventions

Volunteers were randomised for the order methods to induce artificial cough, i.e., whether the Mefar dosimeter was used first or the KoKo DigiDoser. The following assessments were then performed: 1.

Sponsors

Hull and East Yorkshire Hospitals NHS Trust (UK)
Lead Sponsor

Eligibility

Sex/Gender
All

Inclusion criteria

Inclusion criteria: 1. Healthy male/female volunteers 2. Male and female subjects of at least 18 years of age 3. Non-smokers or, ex-smokers of at least 12 months 4. Forced expiratory volume in one second (FEV1) greater than 80% of predicted

Exclusion criteria

Exclusion criteria: 1. Female subjects who are pregnant, or lactating, or who are of child bearing potential but are not using contraceptive measures 2. Suffering from any active seasonal allergies 3. Suffering from concomitant disease which may interfere with study procedures or evaluation. 4. Subjects suffering from gastroesophageal reflux taking proton pump inhibitors or any other regular antacid therapy 5. Subjects suffering from post nasal drip syndrome 6. A recent respiratory tract infection within 6 weeks prior to entry on to study 7. Use of medications known to alter the cough reflex 8. Smoking history of greater than 10 pack years

Design outcomes

Primary

MeasureTime frame
Reproducibility of cough reflex sensitivity to citric acid (measured via inhalation of incremental, doubling concentrations of citric acid until the concentration inducing two or more coughs or five or more coughs is reached)using the modified Devilbiss 646 nebuliser powered by the KoKo DigiDoser. Measured within 1 day comparing baseline challenge and challenges at 1, 2 and 4 hours post-baseline to measure within-day reproducibility.

Secondary

MeasureTime frame
To compare the reproducibility of cough reflex sensitivity using the modified Devilbiss 646 nebuliser powered by the KoKo DigiDoser with that of the more commonly used MB2 nebuliser powered by the MB3 mefar dosimeter. Assessed at baseline and then two weeks later to assess between-day reproducibility.

Countries

United Kingdom

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Mar 31, 2026