Systemic concentrations of salbutamol and HFA-134a after inhalation of salbutamol sulfate in a chlorofluorocarbon-free system

Ther Drug Monit. 1996 Jun;18(3):240-4. doi: 10.1097/00007691-199606000-00004.

Abstract

The objective of this study was to determine if salbutamol was absorbed from a new salbutamol sulfate chlorofluorocarbon (CFC)-free metered-dose inhaler (MDI). Measurement of HFA-134a, the CFC-free propellant, was included to provide proof of delivery of this MDI. Eight healthy men received two inhalations (90 micrograms salbutamol base equivalents per inhalation ex adapter) from the CFC-free inhaler (MDI A) in period 1 and from a reference CFC inhaler (MDI V) in period 2. Eight postdose samples were collected for the determination of salbutamol serum levels over a 4-h period. Salbutamol levels were not quantifiable in most samples. Four subjects given MDI A and two given MDI V had a few transient salbutamol levels, which occurred in the first hour after dosing, within a narrow range of 1-2 ng/ml and close to the lower limit of detection (1 ng/ml). No pharmacokinetic analyses were possible. Blood samples were also collected after MDI A for propellant quantitation. HFA-134a levels were seen in all subjects, verifying absorption. We conclude that the transient salbutamol serum levels can be attributed to the two-inhalation dose and not to either propellant system.

Publication types

  • Clinical Trial
  • Comparative Study

MeSH terms

  • Administration, Inhalation
  • Adolescent
  • Adrenergic beta-Agonists / administration & dosage
  • Adrenergic beta-Agonists / blood
  • Adrenergic beta-Agonists / pharmacokinetics*
  • Adult
  • Aerosol Propellants
  • Albuterol / administration & dosage
  • Albuterol / blood
  • Albuterol / pharmacokinetics*
  • Chlorofluorocarbons, Methane
  • Humans
  • Hydrocarbons, Fluorinated / administration & dosage
  • Hydrocarbons, Fluorinated / blood
  • Hydrocarbons, Fluorinated / pharmacokinetics*
  • Male
  • Middle Aged
  • Nebulizers and Vaporizers

Substances

  • Adrenergic beta-Agonists
  • Aerosol Propellants
  • Chlorofluorocarbons, Methane
  • Hydrocarbons, Fluorinated
  • Albuterol
  • apaflurane