Proper use of a dry powder inhaler (DPI) requires that the patient be able to do which of the fol-lowing?

a. Generate inspiratory flows of 60 L/min or higher.
b. Exhale forcibly through the device before drug delivery.
c. Inhale slowly (<0.5 L/sec) and perform a breath-hold.
d. Coordinate firing of the DPI with inspira-tion.

ANS: A
Individual doses are inhaled as soon as the seal is broken. The high peak inspiratory flow rates (>60 L/min) required to dispense the drug powder from most current DPI designs result in a pharyngeal dose comparable with that received from a typical pressurized metered dose inhaler without an add-on device.