title: Efficacy and duration of salmeterol powder inhalation in protecting against exercise-induced bronchoconstriction.
abstract: BACKGROUND
  The protective effect of a new long acting beta 2-agonist, salmeterol, against exercise-induced bronchoconstriction has been documented when given as inhaled aerosol.
  
  
  OBJECTIVE
  The aim of the present study was to examine the duration of the protective effect of a single dose of salmeterol, 50 micrograms, inhaled as dry powder, against exercise-induced bronchoconstriction.
  
  
  METHODS
  Sixteen patients with reproducible exercise-induced bronchoconstriction were challenged on a treadmill on two prestudy visits and six study days. The patients were challenged 4, 8, and 12 hours postdosing. The study was designed as a double blind placebo-controlled randomized crossover trial.
  
  
  RESULTS
  Statistically significant differences in % maximum fall in PEFR were found at four and eight hours postdosing, in favor of salmeterol. At 12 hours postdosing, no clear statistical inference was possible, owing to the presence of a statistical carry-over effect; however, significant differences in area under curve in favor of salmeterol were found at 4, 8, and 12 hours postdosing.
  
  
  CONCLUSIONS
  Salmeterol, 50 micrograms, dry powder inhalation had a protective effect against exercise-induced bronchoconstriction up to 12 hours postdosing, as compared with placebo. No adverse effects were identified.
authors.affiliation: Dept. of Pulmonary Diseases, Regional Hospital, University of Trondheim, Norway.
authors.forename: J
authors.initials: J
authors.lastname: Schaanning
authors.forename: J
authors.initials: J
authors.lastname: Vilsvik
authors.forename: A H
authors.initials: AH
authors.lastname: Henriksen
authors.forename: G
authors.initials: G
authors.lastname: Bratten
mesh_terms: D000280:Administration, Inhalation; D000293:Adolescent; D000318:Adrenergic beta-Agonists / Q000008:administration & dosage* / Q000494:pharmacology; D000328:Adult; D000420:Albuterol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D001250:Asthma, Exercise-Induced / Q000517:prevention & control*; D016084:Bronchoconstriction / Q000187:drug effects*; D001993:Bronchodilator Agents / Q000008:administration & dosage* / Q000494:pharmacology; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010366:Peak Expiratory Flow Rate / Q000187:drug effects; D011208:Powders; D000068299:Salmeterol Xinafoate; D013997:Time Factors
chemical_list: D000318:Adrenergic beta-Agonists; D001993:Bronchodilator Agents; D011208:Powders; D000068299:Salmeterol Xinafoate; D000420:Albuterol