Pediatric aerosol therapy: new devices and new drugs.

The lung and conducting airways are ideal portals for drug delivery. The airways are easily accessible by oral or nasal inhalation; the airway and alveolar surface is large, allowing for drug dispersion; and many drugs do not cross the airway-blood barrier, permitting the use of higher topical drug doses for airway disease than would be practical with systemic administration. On the other hand, alveolar deposition of drugs allows rapid absorption into the pulmonary circulation and back to the left heart and systemic distribution, bypassing the intestinal tract and liver inactivation. Recently, there has been a feast of new aerosol devices and drug formulations that promise the effective delivery of an amazing array of medications far beyond pressurized metered-dose inhalers and nebulizers and asthma medicines.