title: Age dependent systemic exposure to inhaled salbutamol.
abstract: OBJECTIVE
  To determine the effect of age on systemic exposure to inhaled salbutamol in children.
  
  
  METHODS
  Fifty-eight asthmatic children, aged 3-16 years, inhaled 400 microg of salbutamol from a pressurized metered dose inhaler with spacer. The 20 min serum profile was analyzed.
  
  
  RESULTS
  Prescribing a dose on a microg kg(-1) basis caused reduced systemic exposure in young children (Y) compared with older children (O) (C(max-microg kg(-1)-adjusted) Y : O ratio (95%CI) = 0.55 (0.47, 0.65)) whereas a fixed nominal dose irrespective of age caused increased exposure in young children (C(max) Y : O ratio (95%CI) = 1.7 (1.3, 2.2)).
  
  
  CONCLUSIONS
  For similar systemic exposure, dosing should be adjusted to age or size but not on a fixed microg kg(-1) basis, which may lead to unnecessary suboptimal dosing.
authors.affiliation: Danish Pediatric Asthma Center; Copenhagen University Hospital, Gentofte, Copenhagen, Denmark. kb@copsac.dk
authors.forename: Klaus
authors.initials: K
authors.lastname: Bønnelykke
authors.forename: Jakob Jessing
authors.initials: JJ
authors.lastname: Jespersen
authors.forename: Hans
authors.initials: H
authors.lastname: Bisgaard
mesh_terms: D000280:Administration, Inhalation; D000293:Adolescent; D000367:Age Factors; D000420:Albuterol / Q000008:administration & dosage* / Q000493:pharmacokinetics; D001249:Asthma / Q000188:drug therapy*; D001993:Bronchodilator Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008168:Lung / Q000378:metabolism*; D008297:Male
chemical_list: D001993:Bronchodilator Agents; D000420:Albuterol