Equivalent bronchodilation with salbutamol given via pMDI or Turbuhaler

Several breath-activated multidose powder devices for inhaled anti-asthma drugs are now available. Some of these inhalers have been argued to give higher drug deposition in the airways than conventional pressurized metered dose inhalers (pMDI). The aim of the present study was to compare the efficacy and safety of salbutamol given via pMDI or Turbuhaler (both 100 mu g per inhalation). Adult asthmatic patients of either sex (n = 22) and with reversible airflow obstruction were included in a randomized, placebo-controlled study. On the study days, salbutamol was given with increasing doses (200 to 3,200 mu g cumulative) or placebo, via pMDI or Turbuhaler. A dose-related increase in FEV1 was observed after administration of salbutamol given via either device, versus placebo. The improvement in FEV1 was similar whether salbutamol was given via pMDI or Turbuhaler, at microgram equivalent doses, After a total cumulative dose of 3,200 mu g, mean FEV1 for Turbuhaler was 2.98 (change from baseline of 23.1%), for pMDI 2.93 (change from baseline of 23.6%), and for placebo 2.36 (change from baseline of 0.42%), Changes in potassium, glucose, and heart rate did not show any significant differences between pMDI and Turbuhaler. We conclude that the efficacy of salbutamol is comparable when the drug is given via the Turbuhaler or pMDI.