clinical pharmacology
Overview of Pharmacodynamics
Introduction
Pharmacodynamics (sometimes described as what a drug does to the body) is the study of the biochemical, physiologic, and molecular effects of drugs on the body and involves Drug–Receptor Interactions (including receptor sensitivity), postreceptor effects, and A drug’s pharmacodynamics can be affected by physiologic changes due to A disorder or disease Aging process Other drugs Disorders that affect pharmacodynamic responses include genetic mutations, thyrotoxicosis, malnutrition, myasthenia gravis, Parkinson disease, and some forms ofinsulin-resistant diabetes mellitus. These disorders can change receptor binding, alter the level of binding proteins, or decrease receptor sensitivity. Aging tends to affect pharmacodynamic responses through alterations in receptor binding or in postreceptor response sensitivity (see table). Pharmacodynamic drug–drug interactions result in competition for receptor binding sites or alter postreceptor response. 