Pharmacokinetics and pharmacodynamics for VNs: 2

In order to use drugs safely in animals it is important to understand individual drug pharmacodynamics, or the physiological effects of the drug on the body. This article describes the principles of pharmacodynamics, starting with the different mechanisms by which drugs bound to a receptor can elicit an effect as well as the receptor actions of agonist, partial agonist and antagonist drugs. The terms efficacy and potency in terms of drug action are defined. Different pathways of drug metabolism and elimination are identified and the importance of understanding the relationship between drug pharmacokinetics and pharmacodynamics explained.