Primary Outcomes

Description: The participants were asked by one investigator to fill in a questioner detailing the presence of nasal and eye symptoms (including nasal congestion, rhinorrhea, nasal itching, sneezing and eye itching), and to score each symptom on a 0-10 cm scale; with 0 cm = no symptoms and 10 cm = most severe and bothersome symptom. The same investigator calculated both the individual symptom and the average of the sum of 5 AR symptoms scores, before and at the end of 14 days' treatment. Any subject with a mean score of < 4 cm at baseline was excluded from this study.

Secondary Outcomes

Description: Eccovision acoustic rhinometry was used to measure the nasal cavity volume (NCV) according to standardized recommendations. Measurements of nasal volume were made from the first 2 cm (V2), the first 4 cm (V4), from the first 6 cm (V6), from the segment between 0 and 5 cm (V0-5), and the segment between 0 and 7 cm (V0-7) of the nose. All measurements were performed three times by the same operator, and nasal volumes were calculated as the sum of both nostrils24. In the current study, the change in the nasal cavity volume was measured at 2-5 cm, as this seems to be an important variable for mucosal changes.24 Nasal airway resistance (NAR) was measured by anterior active rhinomanometry in a quiet room at temperature of 25°C and humidity of 70%. NAR was measured at 75 Pa point (R75T).

Description: A nitric oxide analyser was used to measure exhaled nasal nitric oxide (nNO). Briefly, NO-free air was aspirated through the nasal cavity at a flow rate of 50 ml/s. The subject exhaled against the air-resistance, resulting in an intraoral pressure to close the velum and prevent mixture of oral and nasal gas. Nasal gas from this circuit was continuously routed in part directly into the analyser for determination of nNO, and the level of nNO(ppb) was calculated from a plateau lasting for at least 3s.