title: Bronchodilator effects of a fenoterol metered dose inhaler and fenoterol powder in asthmatics with poor inhaler technique.
abstract: Thirty-seven per cent of 204 consecutive asthmatic patients using metered dose inhalers (MDI) regularly had faulty inhaler technique. Twenty patients with poor technique volunteered for bronchomotor tests. The bronchodilator effects of 0.2 mg of fenoterol in MDI form, 0.2 mg of fenoterol in powder form and a placebo powder were compared. Mean peak expiratory flow (PEF) and forced expiratory volume in 1 s (FEV1) values after 0.2 mg of fenoterol in MDI form were only slightly different from those after placebo. Inhalation of 0.2 mg of fenoterol powder was, however, followed by a highly significant (p less than 0.001) increase in measured expiratory indices. PEF and FEV1 values were significantly higher after fenoterol powder than after fenoterol in MDI form (PEF, p less than 0.01 at 5 min, p less than 0.001 at 15 min, and p less than 0.05 at 60 min, FEV1, p less than 0.01 1 h after drug administration). Poor MDI technique can severely impair the effect of bronchodilator drugs. Use of a bronchodilator in powder form is more reliable in these patients.
mesh_terms: D000293:Adolescent; D000328:Adult; D000336:Aerosols; D000368:Aged; D001249:Asthma / Q000188:drug therapy*; D005260:Female; D005280:Fenoterol / Q000008:administration & dosage / Q000627:therapeutic use*; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D010366:Peak Expiratory Flow Rate; D011208:Powders; D012138:Respiratory Therapy / Q000295:instrumentation
chemical_list: D000336:Aerosols; D011208:Powders; D005280:Fenoterol