title: Nebulization of corticosteroids to asthmatic children: large variation in dose inhaled.
abstract: OBJECTIVE
  Despite problems associated with assessing the clinical effect and side effects of nebulized corticosteroids, little is known of the amount of drug that is inhaled by children with asthma or how this is affected by different drug formulations. The aim of this study was to test the hypothesis that children with asthma inhale the same proportion of the prescribed dose of nebulized fluticasone, beclomethasone dipropionate (BDP) and flunisolide.
  
  
  METHODS
  The amount of nebulized drug that would have been inhaled by asthmatic children was captured on filters between the patient and nebulizer, and the amount contained in particles likely to reach the lung (i.e. <5 μm) is determined.
  
  
  RESULTS
  The children studied would have inhaled 13% of the prescribed dose of fluticasone propionate, 21% of BDP and 25% of flunisolide. However, the percentage of the dose inhaled that was contained in particles <5 μm, and therefore more likely to reach the lungs, was only 5% of the prescribed dose of fluticasone propionate, 8% for BDP and 16% for flunisolide. The inter-subject variation coefficient of the dose inhaled was much greater for suspensions of fluticasone propionate (34%) and BDP (45%) than for suspensions of flunisolide solution (9%).
  
  
  CONCLUSIONS
  Our results demonstrate that the prescribed dose may bear little resemblance to the dose delivered from a nebulizer and that the dose inhaled is significantly affected by the drug formulation prescribed.
authors.affiliation: Department of Infection, Inflammation and Immunity, Division of Child Health and Institute of Lung Health, University of Leicester, Leicester, UK.
authors.forename: Chris
authors.initials: C
authors.lastname: O'Callaghan
authors.affiliation: Department of Infection, Inflammation and Immunity, Division of Child Health and Institute of Lung Health, University of Leicester, Leicester, UK.
authors.forename: Judy A
authors.initials: JA
authors.lastname: White
authors.affiliation: Pediatric Cough and Asthma Centre, Bergamo Hospital Institute, Ponte San Pietro, Bergamo, Italy.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Kantar
mesh_terms: D000280:Administration, Inhalation; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology; D002648:Child; D004305:Dose-Response Relationship, Drug; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D009330:Nebulizers and Vaporizers; D012119:Respiration / Q000187:drug effects
chemical_list: D005938:Glucocorticoids
keywords: asthma; beclomethasone dipropionate; flunisolide; fluticasone propionate; inhaled corticosteroid