| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 4211033 | Respiratory Medicine | 2009 | 7 Pages |
SummaryIntroductionRecent developments concerning pressurized metered dose inhalers (pMDIs) with inhaled corticosteroids (ICS) are the introduction of ciclesonide and the replacement of propellants. As the results of in vivo studies depend on pMDIperformance, it is necessary to evaluate pMDIs in vitro for delivered dose and particle size distributions under different conditions.MethodsFluticasone 125 μg, budesonide 200 μg, beclomethasone HFA100 μg, and ciclesonide 160 μg were compared for delivered dose and particle size using laser diffraction analysis with inspiratory flow rates of 10, 20 and 30 l/s.ResultsThe volume median diameter of budesonide was 3.5 μm, fluticasone 2.8 μm, beclomethasone and ciclesonide both 1.9 μm. The mouthpiece retention was up to 30% of the nominal dose for beclomethasone and ciclesonide, 11–19% for the other pMDIs. Lifespan, flow rate, and air humidity had no significant influence on particle size distribution. The delivered dose of beclomethasone, budesonide, and ciclesonide remained constant over the lifespan. The delivered dose of fluticasone 125 decreased from 106% to 63%; fluticasone 250 also decreased whereas fluticasone 50 remained constant.ConclusionsThere is a significant difference in median particle size distribution between the different ICS pMDIs. Air humidity and inspiratory flow rate have no significant influence on particle size distribution. Ciclesonide 160 and beclomethasone 100 deliver the largest fine particle fractions of 1.1–3.1 μm. The changes in delivered dose during the lifespan for the fluticasone 125 and 250 may have implications for patient care.
