ABSTRACT
I. Introduction Asthma therapy was revolutionized in the early 1970s by the introduction of inhaled corticosteroid (ICS) therapy. ICS therapy has subsequently proved to be the most effective anti-inflammatory treatments for asthma control. Because of the success of ICS for asthma and the realization that chronic obstructive pulmonary disease (COPD) is also a chronic inflammatory disease, ICS therapy has been introduced for the treatment of COPD. However, its effectiveness is less evident than its effect in asthma. The use of ICS monotherapy as the gold standard in airways disease has been superseded by the discovery that in combination with long-acting b-agonist (LABA) the effects of ICS can be improved. It is expected that the combination of ICS and LABA will remain the cornerstone of treatment for the next 10 years. Greater understanding of the molecular mechanisms of ICS suggests that new CS molecules will be developed that could provide greater efficacy with a reduced risk of systemic side effects. Further, understanding the mechanisms underlying relative CS insensitivity in asthma and COPD may lead to novel combinations that will restore CS sensitivity in these patients. This chapter will review the mechanisms of CS actions, the effect and optimal use of ICS in asthma and COPD, and the issue of CS insensitivity in airways disease.
