The small airways in asthma

Airway inflammation is the basis for airway hyper-reactivity that results in the signs and symptoms of asthma. Great strides have been made in the past several decades to target airway inflammation using topical inhaled corticosteroids. In some cases, despite reported improvement in large airways indices on treatment, clinical control of asthma is not attained. Inflammation of the distal airways is now realized as playing a greater role in asthma control, and newer techniques are available to assess the smaller airways. Changes in formulations of inhaled corticosteroids and smaller particle size of medication allows for more effective targeting of the smaller airways.