The two main division of pharmacology include pharmacokinetics and pharmacodynamics. Pharmacokinetics refers to the way the body handles drug absorption, distribution, biotransformation, and excretion. Pharmacodynamics is the study of biochemical and physiological effects of drugs and their mechanisms of action.
Drug transport. The movement of drug molecules in the body is subject to absorption, distribution, and excretion. Drugs can cross cellular membranes by various mechanisms. The mechanisms of absorption are similar to the mechanisms of membrane transport: passive diffusion, carrier-mediated diffusion, filtration, active transport, or pinocytosis.
Mechanisms of drug action. Most drugs interact with macromolecular components (called receptors) of a cell or an organism to begin biochemical and physiologic changes which causes drugs observed effects, or response, or primary pharmacological reaction. Receptors bind ligands and transduce signals.
Pharmacology is the science dealing with biochemical and physiologic aspects of drug effects, including absorption, distribution, metabolism, elimination, toxicity doses, and specific mechanisms of drug action.
