title: Time-effect of montelukast on protection against exercise-induced bronchoconstriction.
abstract: BACKGROUND
  Montelukast has been proven to assure a protective effect against exercise-induced bronchoconstriction.
  
  
  OBJECTIVE
  To verify exactly when montelukast begins protection in asthmatic children by evaluating different time intervals between dosing and challenge.
  
  
  METHODS
  In a double blind, placebo-controlled, three day doses, crossover study, patients were randomized to receive in sequence treatment with either a placebo or montelukast and assigned to one of seven groups that were tested 1, 2, 3, 4, 5, 6 and 8 h after drug administration, respectively. For each group, the exercise challenge was always performed at the same hour on the first and third days of treatment.
  
  
  RESULTS
  Sixty-nine asthmatic children took part in the study. On day 3, the mean FEV(1) % fall from baseline was 25.54 (95% CI = 21.63/29.46) and 14.89 (95% CI = 11.85/17.92) for the placebo and active drug (p < 0.05), respectively. On day 1, the mean fall of FEV(1) was 28.20 (95% CI = 24.46/31.94) and 19.01 (95% CI = 15.71/22.31) for the placebo and montelukast (p < 0.05), respectively. Clinical protection was achieved in 21 (30%) and 33 (48%) subjects by montelukast on the first and third days, respectively.
  
  
  CONCLUSIONS
  Montelukast assured protection against exercise-induced bronchoconstriction from the first through the eighth hour from the first day of treatment. However, individual susceptibility to protection was evident since some individuals were not protected at any time. We conclude that in clinical use individual responses to the drug should be carefully evaluated in the follow-up management.
authors.affiliation: Pediatric Department, University of Verona, Verona, Italy. diego.peroni@univr.it
authors.forename: Diego G
authors.initials: DG
authors.lastname: Peroni
authors.forename: Lydia
authors.initials: L
authors.lastname: Pescollderungg
authors.forename: Marco
authors.initials: M
authors.lastname: Sandri
authors.forename: Iolanda
authors.initials: I
authors.lastname: Chinellato
authors.forename: Attilio L
authors.initials: AL
authors.lastname: Boner
authors.forename: Giorgio L
authors.initials: GL
authors.lastname: Piacentini
mesh_terms: D000085:Acetates / Q000494:pharmacology / Q000627:therapeutic use*; D001250:Asthma, Exercise-Induced / Q000188:drug therapy* / Q000503:physiopathology / Q000517:prevention & control; D016084:Bronchoconstriction / Q000187:drug effects*; D002648:Child; D018592:Cross-Over Studies; D003521:Cyclopropanes; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005080:Exercise Test; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006801:Humans; D020024:Leukotriene Antagonists / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D011804:Quinolines / Q000494:pharmacology / Q000627:therapeutic use*; D013440:Sulfides; D013997:Time Factors
chemical_list: D000085:Acetates; D003521:Cyclopropanes; D020024:Leukotriene Antagonists; D011804:Quinolines; D013440:Sulfides; C093875:montelukast