Comparative potency and clinical efficacy of inhaled corticosteroids.

The inhaled corticosteroids (ICSs) are currently the most potent antiinflammatory drugs available for the long-term control of persistent asthma. Physico-chemical modifications of the basic steroid structure result in pharmacodynamic and pharmacokinetic properties that confer both enhanced topical efficacy and diminished systemic activity compared with older corticosteroids such as prednisolone. The purpose of this article is to compare the pharmacodynamic, pharmacokinetic, and lung delivery differences among the products and demonstrate how those differences translate into significant differences in the clinical effectiveness of the ICSs.