title: The pharmacokinetic profile of inhaled and oral salbutamol in elite athletes with asthma and nonasthmatic subjects.
abstract: OBJECTIVE
  Data on pharmacokinetics of inhaled and oral salbutamol in elite athletes with asthma are needed to differentiate between therapeutic use and doping in doping control.
  
  
  METHODS
  An interventional open-label crossover.
  
  
  METHODS
  Respiratory Research Unit, Copenhagen University Hospital, Bispebjerg.
  
  
  METHODS
  Eight elite athletes with asthma and 10 nonasthmatic subjects aged 18 to 33 years.
  
  
  METHODS
  Administration of 0.8 mg of inhaled salbutamol and 8 mg of oral salbutamol separated by 14 days.
  
  
  METHODS
  Urine concentration of free salbutamol.
  
  
  RESULTS
  Maximum urine concentrations peaked in the period of 0 to 4 hours after the administration of inhaled and oral salbutamol in both groups. Median concentrations after inhaled salbutamol and oral salbutamol were 401.6 and 2108.1 ng/mL in healthy subjects and 334.9 and 2975.2 ng/mL in elite athletes with asthma. There were no significant statistical differences between the groups. One sample exceeded the World Anti-Doping Agency threshold value of 1000 ng/mL with a urinary salbutamol concentration of 1057 ng/mL 4 hours after inhalation, when no correction for urine specific gravity was done. When this sample was corrected for urine specific gravity, the result was 661 ng/mL.
  
  
  CONCLUSIONS
  We found no significant difference in pharmacokinetic profile of inhaled and oral salbutamol between elite athletes with asthma and nonasthmatic subjects. Our results indicate that urine salbutamol concentrations should be corrected for urine specific gravity when evaluating doping cases.
authors.affiliation: Respiratory Research Unit, Bispebjerg Hospital, Copenhagen, Denmark. elers@dadlnet.dk
authors.forename: Jimmi
authors.initials: J
authors.lastname: Elers
authors.forename: Lars
authors.initials: L
authors.lastname: Pedersen
authors.forename: John
authors.initials: J
authors.lastname: Henninge
authors.forename: Peter
authors.initials: P
authors.lastname: Hemmersbach
authors.forename: Kim
authors.initials: K
authors.lastname: Dalhoff
authors.forename: Vibeke
authors.initials: V
authors.lastname: Backer
mesh_terms: D000280:Administration, Inhalation; D000284:Administration, Oral; D000293:Adolescent; D058666:Adrenergic beta-2 Receptor Agonists / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D000328:Adult; D000420:Albuterol / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D001249:Asthma / Q000188:drug therapy*; D056352:Athletes; D018592:Cross-Over Studies; D004300:Doping in Sports; D006801:Humans; D008297:Male; D055815:Young Adult
chemical_list: D058666:Adrenergic beta-2 Receptor Agonists; D000420:Albuterol