CH 3 PHARMACOKINETICS Flashcards
The process by which drug molecules move from their site of administration to the blood; movement of nutrients and other substances form the alimentary canal to the circulation:
Absorption
The ability of some tissues to attract, accumulate, and store drugs in high concentrations relative to other tissues:
Affinity
Network of capillaries in the CNS that inhibits many chemicals and drugs form gaining access to the brain:
Blood-brain barrier
The movement of a chemical from an area of higher concentration to an area of lower concentration:
Diffusion
The transport of drugs throughout the body after they are absorbed:
Distribution
Complex that is formed when a drug that binds reversibly to a plasma protein, particularly albumin, that makes the drug unavailable for distribution to its site of action:
Drug-protein complexes
Administration of drugs orally or through nasogastric or gastrostomy tubes:
Enteral route
Tablets that have a hard, waxy coating designed to dissolve in the alkaline environment of the small intestine:
Enteric-coated
Recycling of drugs and other substances by the circulation of bile through the intestine and liver:
Enterohepatic recirculation
Process by which a drug increases the activity of the hepatic microsomal enzymes:
Enzyme induction
The process of removing substances from the body:
Excretion
Tablets or capsules designed to dissolve very slowly, resulting in a longer duration of action for the medication; also called long-acting sustained release:
Extended release
Special anatomic barrier that inhibits many chemicals and drugs from entering the fetus:
Fetal-placental barrier
Mechanism whereby drugs are absorbed, enter in to the hepatic portal circulation, and are inactivated by the liver before they reach the general circulation:
First-pass effect
As it relates to pharmacotherapy, liver enzymes that metabolize drugs as well as nutrients and other endogenous substances; sometimes called the P-450 system:
Hepatic microsomal enzyme system
Multiple, similar forms of an enzyme that perform slightly different metabolic functions:
Isozymes
Relatively large dose of a drug given at the beginning of treatment to rapidly obtain a therapeutic response:
Loading dose
Amount of drug that keeps the plasma drug concentration in the therapeutic range:
Maintenance doses
The process used by the body to chemically change a drug molecule; also called biotransformation:
Metabolism
Amount of drug required to produce a therapeutic effect:
Minimum effective concentration
Study of drug movement throughout the body:
pharmacokinetics
The length of time required for the plasma concentration of a drug to decrease by one half after administration:
Plasma half-life (t 1/2)
Drugs that become more active after they are metabolized:
Prodrugs
Drug that is metabolized by a CYP enzyme:
Substrate
