title: Lung bioavailability of hydrofluoroalkane fluticasone in young children when delivered by an antistatic chamber/mask.
abstract: OBJECTIVE
  To determine whether an antistatic valved holding chamber/mask improves lung bioavailability of hydrofluoroalkane (HFA) fluticasone in young children.
  
  
  METHODS
  Twelve patients, age 1 to 6 years, with well-controlled asthma were treated with an HFA fluticasone metered-dose inhaler (Flovent HFA) twice daily (440 microg/day). The drug was delivered by tidal breathing through conventional (AeroChamber Plus) and antistatic (AeroChamber MAX) valved holding chambers (VHCs) with masks in a randomized, crossover manner, each for 3 to 7 days. When adherence was 100% at home, blood was collected for measurement of steady-state fluticasone plasma concentration (FPC) 1 hour after the last dose was administered in the clinic. FPC indicates systemic exposure directly and airway delivery indirectly. It was measured by liquid chromatography-mass spectrometry. Data were analyzed by regression analysis.
  
  
  RESULTS
  The mean +/- SD FPC was 107 +/- 30 pg/mL after conventional VHC and 186 +/- 134 pg/mL after the antistatic VHC (P = .03). In 5 patients (40%), the antistatic VHC increased FPC by >/= 100%, to potentially excessive levels in 4 of them; it had little effect in 7 patients.
  
  
  CONCLUSIONS
  HFA fluticasone was delivered to the airways by both devices even though the patients could not inhale deeply and breath hold. The antistatic VHC variably increased lung bioavailability. To reduce systemic exposure, the dose should be weaned to the minimum required to maintain asthma control.
authors.affiliation: Department of Pharmacy Practice and Pharmaceutics, College of Pharmacy, University of Florida, Gainesville, FL, USA.
authors.forename: Yasmeen
authors.initials: Y
authors.lastname: Khan
authors.forename: Yufei
authors.initials: Y
authors.lastname: Tang
authors.forename: Guenther
authors.initials: G
authors.lastname: Hochhaus
authors.forename: Jonathan J
authors.initials: JJ
authors.lastname: Shuster
authors.forename: Terry
authors.initials: T
authors.lastname: Spencer
authors.forename: Sarah
authors.initials: S
authors.lastname: Chesrown
authors.forename: Leslie
authors.initials: L
authors.lastname: Hendeles
mesh_terms: D000280:Administration, Inhalation; D000730:Androstadienes / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D001682:Biological Availability; D002648:Child; D002675:Child, Preschool; D018592:Cross-Over Studies; D005260:Female; D000068298:Fluticasone; D006801:Humans; D006845:Hydrocarbons, Fluorinated / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D007223:Infant; D008168:Lung / Q000378:metabolism*; D008297:Male; D008397:Masks; D055672:Static Electricity; D005466:Fluorocarbons
chemical_list: D000730:Androstadienes; D000068298:Fluticasone; D006845:Hydrocarbons, Fluorinated; C094049:apaflurane; D005466:Fluorocarbons