study of how drugs produce their effects on desired cells and how a drug is processed by the body; study of biochemical and physiolofic effects of drugs and their mechanisms of action
target cell
general term referring to a large number of cells, all of which are similar, on which a particular drug is intended to act
drug-drug interaction
an interaction between two or more drugs administered to a patient, resulting in either an increas or a decrease in the therapeutic effects of one or more of the drugs, or an adverse effect.
metabolite
any substance produced by the metabolic process
pharmacokinetics
study of the time course of a drug and its metabolites in the body following drug administration
absorption
process by which a drug is moved from the site of administration into the bloodstream
distribution
process by which an absorbed drug is moved from the bloodstream to body tissues or receptors
passive diffusion
passive transport across a cell membrane; drug molecules move from an area of high concentration into an area of low concentration
facilitated diffusion
carrier protein permits specific molecules to pass through certain parts of the cells, requires energy
active transport
certain substances are permitted to accumulate outside the cells
the accumulation generates concentration gradient that will permit transportaion of substance from outside the cell into the cell
pinocytosis
the cell engulfs substance and permits substance to enter the cell, requires energy
bioavailability
degree to which a drug becomes available to body tissues after administration
addiction
pattern of compulsive substance abuse characterized by continued psychological and physiological craving or need for the substance and its effects
tolerance
when a person requires (psychologically or physiolofically) larger doses of a drug to achieve same effect