TY - JOUR T1 - Bioavailability of Beclometasone From Two HFA-BDP Formulations With a Spacer JF - Respiratory Care SP - 1222 LP - 1230 DO - 10.4187/respcare.06689 VL - 64 IS - 10 AU - Amira SA Said AU - Salahdein AbuRuz AU - Henry Chrystyn Y1 - 2019/10/01 UR - http://rc.rcjournal.com/content/64/10/1222.abstract N2 - BACKGROUND: The drug delivery characteristics of each inhaler/spacer combination are unique. The spacer size as well as the presence of electrostatic charge greatly influence the inhaler dose emission and in vivo delivery. Using a previously developed urinary pharmacokinetic method, we have measured the relative lung and systemic bioavailability of beclometasone dipropionate (BDP) after inhalation from 2 hydrofluroalkane-beclometasone dipropionate (HFA-BDP) formulations when used with a spacer.METHODS: 12 healthy volunteers received 8 randomized doses, separated by 7 d, of inhaled of BDP with either the Clenil pressurized metered-dose inhaler (pMDI; 250 μg) or the breath-actuated Qvar Easi-Breathe inhaler (100 μg), used alone or with a spacer. The urinary amounts of BDP excreted and retained in the spacer were assayed using a liquid chromatographic mass spectrometer. The spacer was assessed after washing with a detergent solution that was either rinsed or not rinsed with water. In addition, the aerodynamic characterization of each inhaler/spacer combination was assessed using the Andersen Cascade Impactor operated at 28 L/min using a 4-L inhalation volume. The amount of BDP deposited in the induction port, spacer, and various Anderson Cascade Impactor stages were determined.RESULTS: The in vivo 30-min urinary excretion and the in vitro fine particle dose results were only slightly affected by adding the spacer to the Clenil pMDI or the Qvar Easi-Breathe inhaler. However, the spacer significantly reduced drug particle impaction in the oropharynx and minimized deposition in the gastrointestinal tract. Therefore, using spacers with BDP inhalers is associated with a more favorable therapeutic ratio because it has little effect on lung dose, but it significantly reduced throat deposition. An improved lung deposition was achieved with non-rinsed spacers compared to spacers rinsed with water.CONCLUSION: The difference in the BDP particle size between formulations as well as spacer size greatly affected drug deposition in different regions of the respiratory tract. ER -