Exhaled and nasal nitric oxide measurement in the evaluation of chronic cough

Chronic cough is one of the most common and troublesome nonspecific respiratory symptom for which patients seek a general practitioner and specialist advice. It is conventionally defined as a cough lasting for more than 8 weeks. Exhaled nitric oxide has proven to be a specific biomarker capable to discriminate between differential diagnoses of chronic cough and simultaneously provide information about the response to specific treatment. In this review, we will discuss the potential use of exhaled and nasal nitric oxide in the diagnosis of chronic chough. •Chronic cough is one of the most common and troublesome nonspecific respiratory symptom.•FeNO has proven to be a specific biomarker capable to discriminate between differential diagnoses of chronic cough.•FeNO may provide information about the response to specific treatment.