Airway rehydration and cough

  • Research type

    Research Study

  • Full title

    Effect of upper airway rehydration on chronic cough and other laryngeal hypersensitivity symptoms: an exploratory study



  • Contact name

    Kian Fan Chung

  • Contact email

  • Sponsor organisation

    Research Governance and Integrity, Imperial College London and Imperial College Healthcare NHS Trust

  • Duration of Study in the UK

    1 years, 0 months, 0 days

  • Research summary

    Chronic cough is one of the commonest clinical problems encountered by doctors both in general and hospital practice that can persist for months and years. It remains a difficult problem to manage because of our poor understanding of what causes it and we have very few effective treatments to control it. Because those with a chronic cough report that changes in ambient temperature, laughing, talking on the phone for more than a few minutes, aerosol sprays, or smoky atmospheres trigger bouts of coughing, it is thought that this is caused by a state of hypersensitivity that may be caused by damage to the nerves in the back of the throat and in the voice box.
    The lungs emit 25% of daily amount of water lost in moistening the dry air that we inhale which results in water evaporation from the upper airway mucus and from exhalation of moist air (13). We have put forward the possibility that loss of water from the surface of the throat and voice box that happens in dry weather and when we speak leads to a drying process that will serve to stimulate the hypersensitive nerves in this area, creating this hypersensitivity that leads to the chronic cough. It is possible to rehydrate these surfaces by nasal inhalation of hypertonic salt droplets and we wish to find out whether this rehydration process will help reduce chronic cough. Therefore, in this project, we wish to find out whether the airway surface of the throat and voice box is dehydrated in people with a chronic cough and whether when one restores the hydration of this surface the cough would be improved.

  • REC name

    London - Surrey Borders Research Ethics Committee

  • REC reference


  • Date of REC Opinion

    22 Nov 2022

  • REC opinion

    Favourable Opinion