Administration of Inhalable Hypertonic saline 7% + Hyaluronan 0.1% 5 ml twice a day, after bronchodilator for one month.

A judgment on acceptability and global pleasure of the inhalation was weekly reported by patients on a diary, expressed on a 1-10 scale: a score lower than 6 was considered unfavourable.

A judgement on the symptom cough, one of the most important causes of HS intolerance and poor compliance to HS treatment, was weekly reported by patients on a diary, as assessed on a scale of four grades (absent, mild, moderate, severe).

A judgement on the sensation of saltiness, one of the most important causes of HS intolerance and poor compliance to HS treatment, was weekly reported by patients on a diary, as assessed on a scale of four grades (absent, mild, moderate, severe).

A judgement on the sensation of throat irritation, one of the most important causes of HS intolerance and poor compliance to HS treatment, was weekly reported by patients on a diary, as assessed on a scale of four grades (absent, mild, moderate, severe).

Secondary outcome was the effect on respiratory function. A sequence of spirometries was performed as follows. A spirometry was performed in basal conditions, then 400 ug of salbutamol were administered and spirometry was performed again after 15 minutes. Whitin 30 minutes, the first dose of the randomized formulation was administered for 15 minutes and a third spirometry was performed 30 minutes after the inhalation. This sequence was repeated 4 weeks later, with the administration of the last dose of treatment.

Delta FEV1 was calculated as follows: [(FEV1 after randomized solution inhalation - FEV1 after bronchodilator)/FEV1 after bronchodilator]x 100. Delta FEV1 was the outcome measure used to compare the two groups of treatment both at the first dose of the four-weeks treatment and at the end (last dose)of the four-weeks treatment.