Pulmonary drug delivery. Part I: physiological factors affecting therapeutic effectiveness of aerosolized medications

Br J Clin Pharmacol. 2003 Dec;56(6):588-99. doi: 10.1046/j.1365-2125.2003.01892.x.


As the end organ for the treatment of local diseases or as the route of administration for systemic therapies, the lung is a very attractive target for drug delivery. It provides direct access to disease in the treatment of respiratory diseases, while providing an enormous surface area and a relatively low enzymatic, controlled environment for systemic absorption of medications. As a major port of entry, the lung has evolved to prevent the invasion of unwanted airborne particles from entering into the body. Airway geometry, humidity, mucociliary clearance and alveolar macrophages play a vital role in maintaining the sterility of the lung and consequently are barriers to the therapeutic effectiveness of inhaled medications. In addition, a drug's efficacy may be affected by where in the respiratory tract it is deposited, its delivered dose and the disease it may be trying to treat.

Publication types

  • Review

MeSH terms

  • Absorption
  • Administration, Inhalation
  • Aerosols / pharmacokinetics
  • Bronchi / anatomy & histology
  • Bronchi / blood supply
  • Forced Expiratory Volume / physiology
  • Humans
  • Lung / physiology*
  • Particle Size
  • Pharmaceutical Preparations / administration & dosage*
  • Pharmaceutical Preparations / metabolism


  • Aerosols
  • Pharmaceutical Preparations