This is a simple non-invasive test that takes 5 minutes. Nitric oxide content is measured from a patient’s exhalation breath. When exhaled nitric oxide is raised, there is likely an eoesinophilic inflammation in the airways that can occur in asthma and eosinophilic bronchitis. This test can be done in patients as young as 5 year old if they can follow instructions well.
See condition on chronic cough