Device factors affecting pulmonary delivery of dry powders.

The use of orally inhaled dry powder technologies is one way of delivering medicines to the lung for treating local conditions or for achieving systemic effect. These involve dry powder formulations containing an active pharmaceutical ingredient together with inhaler devices. These powder/device systems enable patients to inhale and aerosolize the medicine into suitably sized particles that deposit in the lung. Several inhaler centric aspects of these delivery systems are presented and discussed in context of new product development. Case examples are provided to highlight several inhaler aspects and to guide development of powder/inhaler systems.