# pharmacokinetics Flashcards

pharmacokinectics

quantitative expression of relationship between absorption, distribution and elimination of drugs as a function of time

the effect of the drug is related to what

blood [drug]

One compartment model

drug rapidly equilibrates between plasma and tissue relative to elimination rate

semi-log plot of [plasma] over time, describe graph when drug follows first order kinetics for one-compartment model

straight line with

changes in [plasma] reflects proportional change in concentration of drug where

tissue

does drug distribute to all tissues

no

how long does it take for drug to equilibriate in 2-compartment model

longer

what are the two compartments in the model

central and peripheral

in 2 compartment model, where does elimination occur

central compartment.

what are the 2 phases in semi-log plot when drug follows first order kinetics for 2 compartment model

initial distribution

elimination phase

definition of elimination kinetics first order

rate of decrease in [drug] is directly proportional to the amount of drug in body

elimination kinetics first order, what fraction of the drug is eliminated

constant

most drugs follow what order of kinetics

first

define elimination rate constant (ke)

fraction of drug removed at any given time is constant and independent of dose

semi-plot for one compartment first order kinetics will look like

straight linear line

define zero order for elimination kinetics

constant amount of drug eliminated independent of dose

describe the enzymes involved in zero order elimination kinetics

saturated

define bioavailability

fraction of unchanged drug reaching systemic circulation after drug administration

drugs administered by intravenous route have a bioavailability of what

1

all other routes besides IV of administration have a bioavailability of

less than or equal to 1

what letter represents bioavailability

F

how is bioavailability determined after IV or other administration

measure [plasma] as function of time

name two drug examples for 0 order kinetics

asprin

alcohol