FeNO measurement is a validated non-invasive technique, which
is used for diagnosis and monitoring of asthma. It would be
desirable to find a reliable method to monitor allergic rhinitis (AR)
via measurement of FeNO, and/or nasal nitric oxide (nNO). The
aim of our study was the assessment of the efficacy of FeNO and
nNO as markers in AR treatment. FeNO and nNO were measured
with the portable NO analyser (NIOX MINO®) in healthy
participants and in patients with AR. The patients were examined
during the pollen season and out of it. The effect of local
corticosteroids and antihistamine therapy was observed in
patients with AR during pollen season after three weeks of
therapy. There are significant differences between FeNO and
nNO in patients with AR compared to healthy controls at all set
points of measurements. While FeNO responded well to the
treatment with both antihistamines and combined therapy, nNO
decreased only after combined therapy with antihistamines and
nasal corticosteroids. nNO monitoring alone is not a suitable
method to monitor inflammation of the upper airways in AR and
its suppression by anti-allergic treatment and should be
correlated with other markers as FeNO or symptom scores.