Post-inhalation bronchoconstriction by beclomethasone dipropionate: a comparison of two different CFC propellant formulations in asthmatics.
OBJECTIVE
To assess the change in bronchial response to cumulative doses from two beclomethasone dipropionate metered-dose inhalers (MDI), each using chlorofluorocarbon (CFC) propellants, in asthma patients previously showing falls in forced expiratory volume in 1 s (FEV1) shortly after exposure to beclomethasone MDI.


METHODS
A total of 18 patients were randomized to a single-blind, three-period cross-over treatment regimen, whereby each was administered increasing doses of control mixture (containing surfactant and CFC propellants) or beclomethasone, formulated as either Becloforte or Respocort (250-1000 microg per dose; cumulative dose 2000 microg). Bronchial response was measured by comparison of FEV1 values pre- and post-inhalation.


RESULTS
Respocort formulation produced the least post-dose mean maximum reduction in FEV1 (0.36 +/- 0.17 L; 14.3 +/- 7.2% of baseline FEV1), while the reduction caused by the control was similar (0.40 +/- 0.18 L; 16.2 +/- 9.9% of baseline FEV1). Becloforte produced a significantly greater maximum reduction in FEV1 than Respocort (0.55 +/- 0.32 L, P = 0.003; 22.0 +/- 15.3% of baseline FEV1, P = 0.005). No serious adverse events were reported, but four patients experienced falls in FEV1 of greater than 15% (three on Becloforte, one using the control).


CONCLUSIONS
The incidence of falls in FEV1 following use of beclomethasone MDI was low and generally not serious even in a selected population. The Becloforte preparation produced significantly more post-dose bronchoconstriction than the Respocort formulation, perhaps because of differences in the composition of the surfactant and/or CFC propellant mixtures used to formulate each of the aerosols.
Ruffin
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RE
Respiratory Medicine Unit, The Queen Elizabeth Hospital, Woodville, South Australia, Australia. richard.ruffin@adelaide.edu.au
Campbell
D A
DA
Chia
M M
MM
D000280:Administration, Inhalation; D000287:Administration, Topical; D000328:Adult; D000368:Aged; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage / Q000009:adverse effects*; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000009:adverse effects*; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology; D001507:Beclomethasone / Q000008:administration & dosage / Q000009:adverse effects*; D016084:Bronchoconstriction / Q000187:drug effects*; D005617:Chlorofluorocarbons, Methane; D018592:Cross-Over Studies; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D005938:Glucocorticoids / Q000009:adverse effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D016037:Single-Blind Method; D013501:Surface-Active Agents
D018927:Anti-Asthmatic Agents; D000893:Anti-Inflammatory Agents; D005617:Chlorofluorocarbons, Methane; D005938:Glucocorticoids; D013501:Surface-Active Agents; D001507:Beclomethasone