1.1 Fractional exhaled nitric oxide (FeNO) testing is recommended as an option to help diagnose asthma in adults and children:
who, after initial clinical examination, are considered to have an intermediate probability of having asthma (as defined in the British guideline on the management of asthma 2012) and
when FeNO testing is intended to be done in combination with other diagnostic options according to the British guideline on the management of asthma (2012).
Further investigation is recommended for people whose FeNO test result is negative because a negative result does not exclude asthma.
1.2 FeNO measurement is recommended as an option to support asthma management (in conjunction with the British guideline on the management of asthma 2012) in people who are symptomatic despite using inhaled corticosteroids.