Pharmacology Key Terms: Tolerance, First Pass, Synergistic Effect, Receptor Drugs, Therapeutic Index, Steady State, Half-Life, Drug Classification, Contraindications, Mechanism of Action, Onset, Peak Level

tolerance

reduced response to a drug after prolonged use

first pass effect

-The initial metabolism in the liver of a drug absorbed from the gastrointestinal tract before the drug reaches systemic circulation through the bloodstream

-large proportion of a drug is chemically changed into inactive metabolites by the liver

- bigger dose needed for oral route

synergistic effect

1+1 > 2, drugs that work better together/work to a higher degree (think working better as a team than individually)

agonist

drug that binds to and stimulates the activity of one or more receptors in the body

antagonist

drug that binds to and inhibits the activity of one or more receptors in the body

also called inhibitors

narrow therapeutic index

larger the therapeutic window - the safer the drug

smalled the therapeutic window - more harm to patient

a ratio between the toxic and therapeutic concentrations of a drug

steady state

the physiologic state in which the amount of drug removed via elimination is equal to the amount of druge absorbed with each dose

half-life

time required for half (50%) of a given drug to be removed from the body

drug classification

method of grouping drugs; may be based on structure or therapeutic use

contraindication

any condition, especially one related to a disease state or patient characteristic, including current or recent drug therapy, which renders a particular form of treatment improper or undesirable

mechanism of action

how does a drug work on a cellular level

receptor and ligands -- ligands bind to receptor, the better the fit the better the medication response, poor fit, no pharmacologic response

onset

the time required for a drug to elicit a theraeutic response after dosing

peak level

highest blood level of drug

maximum concentration of a drug in the body after administration, usually measured in a blood sample for therapeutic drug monitoring