RT Book, Section A1 Shargel, Leon A1 Wu-Pong, Susanna A1 Yu, Andrew B.C. SR Print(0) ID 56606660 T1 Chapter 19. Relationship between Pharmacokinetics and Pharmacodynamics T2 Applied Biopharmaceutics & Pharmacokinetics, 6e YR 2012 FD 2012 PB The McGraw-Hill Companies PP New York, NY SN 978-0-07-160393-5 LK accesspharmacy.mhmedical.com/content.aspx?aid=56606660 RD 2024/11/07 AB In the previous chapters, pharmacokinetics was used to develop dosing regimens for achieving therapeutic drug concentrations for optimal safety and efficacy. The interaction of a drug molecule with a receptor causes the initiation of a sequence of molecular events, resulting in a pharmacodynamic or pharmacologic response. The term pharmacodynamics refers to the relationship between drug concentrations at the site of action (receptor) and pharmacologic response. Pharmacodynamics includes the biochemical and physiologic effects that result from the interaction of the drug with the receptor. Early pharmacologic research demonstrates that the pharmacodynamic response produced by the drug depends on the chemical structure of the drug molecule and the affinity of the drug at the receptor site. The drug affinity for the receptor site and the resultant pharmacodynamic response is referred to as the intrinsic activity of the drug. Drug receptors interact only with drugs of specific chemical structure, and the receptors are classified according to the type of pharmacodynamic response induced. Drugs may be considered a full agonist, partial agonist, or antagonist, depending upon the type of drug interaction with the receptor and the resulting pharmacodynamic response (see discussion below).