A NOVEL MULTIPLE-DOSE POWDER INHALER - SALBUTAMOL POWDER AND AEROSOL GIVE EQUAL BRONCHODILATATION WITH EQUAL DOSES

Twenty adult patients with stable asthma were treated with cumulativel y increasing doses of salbutamol delivered from a metered dose inhaler (MDI) and from a novel multiple dose powder inhaler (MDPI), Easyhaler , in a randomized 3-period crossover study. Four doses of salbutamol ( delivered doses to the patient: 90, 90, 180, 360 mu g; cumulative dose of 720 mu g) were administered during each of the three study days an d were inhaled every 30 minutes. Drug doses were released from the pow der inhaler either before or during inhalation. Spirometry was perform ed at the beginning of each study day and 20 minutes after each dose. The lung function parameters after cumulative dosing of salbutamol wer e equal during each study day. The maximal percentage changes in force d expiratory volumes in one second after 720 mu g of salbutamol were 2 4% with the MDI and 23% and 24% with the Easyhaler inhaler, respective ly. Ten patients reported mild side effects when using the MDI, three when the powder was released before inhalation and five when the MDPI was actuated during inhalation. No significant changes in heart rate o r blood pressure were observed during the study. We conclude that the novel multiple dose powder inhaler is clinically equally effective and slightly better tolerated than conventional metered dose inhaler when equal doses of salbutamol are inhaled by asthmatic patients.