Dry powder inhalation for pulmonary delivery: Recent advances and continuing challenges

The pulmonary route of administration is used to treat respiratory and systemic diseases and has gained increasing importance in the field of drug delivery due to its unique advantages including targeted delivery, improved convenience, and rapid onset. In light of some remarkable improvements in the development of dry powder inhaler (DPI) devices and formulations over the last few years, there continues to be a need for further optimized DPI systems. Recently, researchers have focused on finding ways to enhance dry powder inhalation therapy by improving the physicochemical characteristics of the powder formulation and optimizing the device performance. The aim of this chapter is to review the most recent advances in DPI technology. Accordingly, we provide a review of the most recent reported improvements in DPI design, mechanisms of powder dispersion, dry powder composition, and delivery and characterization methods for DPI products.