ABSTRACT
The ß-agonists albuterol, terbutaline, and fenoterol are frequently prescribed in a variety of dosage forms for the treatment of asthma. This chapter reviews the newest developments in clinical pharmacokinetics and pharmacokinetic/dynamic modeling. Epinephrine is the lead compound for ß-agonists. ß2-Agonists feature at least one asymmetric C-atom. The most dominant side effect of ß-agonists is a tremor of the skeleton muscles, most visible in the hand regions. Epidemiological studies have linked the prescription of certain ß2-agonists to an increase in asthma mortality. The pharmacokinetics of ß2-agonists are influenced by stereoselective properties. The oral bioavailability of ß2-agonists is highly variable among patients and related to differences in the absorption but not the presystemic metabolism. Inhalation is the main form of administration for ß2-agonists and represents the dosage form of choice for therapy with ß2-agonists. The sublingual administration has been tested to overcome the first pass effect of ß2-agonists.
