Small airway asthma therapy, challenges, and the future.

The clinical significance of small airway pathology makes these passages an important therapeutic target in asthma. Conventional chlorofluorocarbon-based formulations of inhaled corticosteroids for asthmatic inflammation produce aerosols with a relatively large particle size, and as such, offer poor access to the small airways. New corticosteroid formulations use hydrofluoroalkane propellants with a smaller average particle size, allowing better access to the distal lung. By extending the delivery of this medication to the peripheral lung and by increasing the efficiency of lung targeting, these new corticosteroid formulations provide more effective treatment at reduced drug doses.