Pharm: Ch 2 Basic Concepts and Processes Key Terms Flashcards
process that occurs from the time a drug enters the body to the time it enters the bloodstream to be circulated
Absorption
any undesired responses to medication administration
Adverse effects
drug that produces effects similar to those produced by naturally occurring hormones, neurotransmitters, and other substances
Agonist
drug that inhibits cell function by occupying receptor sites
Antagonist
substance that relieves, prevents, or counteracts the effect of a poison
Antidote
portion of a drug dose that reaches the systemic circulation and is available to act on body cells
Bioavailability
when drugs are altered from their original form into a new form by the body; also referred to as metabolism
Biotransformation (Metabolism)
Drug distribution into the central nervous system (CNS) is limited because the blood–brain barrier, composed of capillaries with tight walls, limits the movement of drug molecules into brain tissue. Only drugs that are lipid soluble or have a transport system can cross the blood–brain barrier and reach therapeutic concentrations in brain tissue.
Blood-brain barrier
transport of drug molecules within the body; after a drug is injected or absorbed into the bloodstream, it is carried by the blood and tissue fluids to its sites of action, metabolism, and excretion
Distribution
Frequency, size, and number of doses- major determinants of drug actions and responses, both therapeutic and adverse.
Dosage
drugs or metabolites that are excreted in bile, reabsorbed from the small intestine, returned to the liver, metabolized, and eventually excreted in urine
Enterohepatic recirculation
production of larger amounts of drug-metabolizing enzymes by liver cells; process accelerates drug metabolism because larger amounts of the enzymes (and more binding sites) allow larger amounts of a drug to be metabolized during a given time
Enzyme induction
process in which a molecule binds to enzymes and inhibits their activity
Enzyme inhibition
elimination of a drug from the body; effective excretion requires adequate functioning of the circulatory system and of the organs of excretion (kidneys, bowel, lungs, and skin)
Excretion
initial metabolism of some oral drugs as they are carried from the intestine to the liver by the portal circulatory system prior to reaching the systemic circulation for distribution to site of action
First-pass effect
immune-mediated reaction to a drug
Hypersensitivity
dose larger than the regular prescribed daily dosage of a medication; used to attain a therapeutic blood level
Loading dose
quantity of drug that is needed to keep blood levels and/or tissue levels at a steady state or constant level
Maintenance dose
toxic or damaging effect of a substance on the kidney; potentially serious because renal damage interferes with drug excretion, causing drug accumulation and increased adverse effects
Nephrotoxicity
the study of how a person’s genetic heritage leads to variable responses to drugs; more generally refers to genetic polymorphisms that occur in a patient population, such as an ethnic group, as opposed to an individual person
Pharmacogenomics
reactions between living systems and drugs; drug actions on target cells and the resulting alterations in cellular biochemical reactions and functions
Pharmacodynamics
drug movement through the body to reach sites of action, metabolism, and excretion
Pharmacokinetics
the occurrence of two or more clearly different forms (or phenotypes) in a species important in drug therapy because it explains the functionally different response to drugs in a general patient population or a specific individual
Polymorphism
initially inactive drugs that exert no pharmacologic effects until they are metabolized
Prodrugs
Drug molecules bound to plasma proteins (mostly Albumin) are pharmacologically inactive because the complex’s large size prevents them from leaving the bloodstream through the small openings in capillary walls and reaching their sites of action, metabolism, and excretion.
Protein binding
laboratory measurement of the amount of a drug in the blood at a particular time
Serum drug level
time required for the serum concentration of a drug to decrease by 50%; also called elimination half-life
Serum half-life
