Many patients with acute and chronic airway diseases suffer from tiredness, fatigue and limited daytime performance. These symptoms result from bronchial obstruction in sleep. Inhalative LABA are a main therapy of obstructive airway diseases. The long acting bronchodilation is especially good for reducing nocturnal airway discomfort. This study should clarify, if the effect of LABA on bronchial obstruction and sleep quality can be verified in the course of therapy with acoustic recording. We studied 11 patients (8 men, 3 women) with exacerbated obstructive airway disease (6 COPD, 5 bronchial asthma) and wheezing. The mean age was 53±11 years (range from 32 to 68 years). The mean FEV1 was decreased (58.7±21.6%). The prospective study was done in 3 consecutive nights with polysomnography and a combined acoustic recording of lung sounds with PulmoTrack. After a first night without medication 2 nights with inhalation of 50 µg Salmeterol were performed. Nocturnal bronchial obstruction could be verified in all 11 patients. The wheezing time was clearly reduced in the second and third night with therapy (p=0.07 resp. p<0.05). All patients had a disordered sleep structure with many arousals and reduced deep sleep and REM sleep (deep sleep 12±7%, REM sleep 16±6%). A small improvement in sleep quality was seen under therapy (p<0,05 for the part of deep sleep). The long term monitoring of lung sounds, which was used in this study, is a reasonable and efficient method for objectifying bronchial obstructions. The effect of disordered breathing in a form of bronchial obstructions was shown, as well as an improvement of sleep quality while using LABA. With improved technology it can be easily used for the assessment of the effectiveness of the antiobstructive therapy in patients with COPD or bronchial asthma.