A valved holding chamber does not decrease the bronchodilator activity of budesonide-formoterol combination metered dose inhaler.

Objective: Spacers and valved holding chambers (VHCs) were developed to facilitate using pressurized metered dose inhaler (pMDI) by patients who could not coordinate the actions required for successful pMDI use. There is little in vivo evidence about how VHC may affect the bronchodilation from combination drugs in pMDI. This study was to determine the effect, if any, of VHC on the bronchodilating actions of the pMDI budesonide/formoterol combination.