ABSTRACT
I. Introduction The delivery of drug to the lungs via the inhaled route has long been established as a successful and effective approach in the management of respiratory disorders (1). Inhalation therapy confers distinct therapeutic benefits by targeting drug directly to the lungs, which allows a more rapid onset of action, the use of smaller drug doses, and a better efficacy to safety ratio, compared with systemic therapy. Increasingly, the respiratory tract is also being used as a conduit for the systemic administration of drug. This chapter reviews the existing inhalation devices in clinical use, new and emerging inhaler technologies, the factors controlling the deposition of inhaled drug within the airways, and aerosols for systemic delivery of drug.
