PHARMACOKINETIC PHARMACODYNAMIC ASPECTS OF AEROSOL THERAPY USING GLUCOCORTICOIDS AS A MODEL/

Glucocorticoids are predominantly prescribed in asthma therapy as aero sols to achieve high pulmonary effects with reduced systemic spill-ove r and pronounced pulmonary selectivity A variety of pharmacokinetic pa rameters are potentially important for determining pulmonary selectivi ty. The intent of this article, is to provide a practice-relevant theo retical approach to put the importance of these parameters on pulmonar y targeting using pharmacokinetic/pharmacodynamic modeling as a tool i n perspective. The applied pulmonary pharmacokinetic/pharmacodynamic m odel revealed that, in addition to recognized parameters such as syste mic clearance, oral bioavailability, and efficiency of pulmonary depos ition, other factors, such as the pulmonary release (dissolution) rate and dose, are relevant. However, the volume of distribution (for effe ct parameters not undergoing a diurnal rhythm) and the receptor affini ty of a given glucocorticoid are not important for achieving lung targ eting.