Inhaled albuterol powder for the treatment of asthma--a dose-response study

Many patients are unable to obtain optimal benefit from inhaled bronchodilators as delivered by metered-dose aerosol spray because of difficulty in synchronizing release of medication with the start of inspiration. The Rotahaler is a flow-activated device that avoids this problem since the act of inspiration itself delivers medication to the lungs. In this randomized, double-blind, crossover study, each of 20 male patients with moderate to severe asthma, ages 12 to 23 yr, received a single treatment with 100, 200, or 400 mcg of albuterol powder or placebo by Rotahaler on 4 study days separated by 2 to 10 days. All patients stopped theophylline and inhaled beta-agonists as needed 24 and 12 hr, respectively, before study days. All patients emptied the Rotahaler with a single inhalation. Pulmonary functions were followed for 8 hr after medication. Statistical analyses of FEV1, FEF25-75, and FVC revealed that all doses of albuterol powder were superior to placebo within 5 min with a log dose-response trend for both degree and duration of bronchodilation.