Intro Topics Flashcards
Pharmacokinetics
Quantitative study of the
absorption, distribution, metabolism, excretion of injected/inhaled drugs & their metabolites
What body does to drug
Pharmacodynamics
study of intrinsic sensitivity (responsiveness) of receptors to a drug & mechanisms by which these effects occur
What drug does to body
Chirality & Enantiomers
mlc that has chiral center
Enantiomers are pair of mlcs that are mirror images & cant be superimposed
-labeled by the way they rotate light dissolved in a solution (d=clockwise l= counterclockwise)
Racemic Mixture
2 enantiomers present in equal proportions
-Don’t rotate polarized light
Stereoselective vs Stereospecific
Stereoselective: relative difference b/w enantiomers
Stereospecific: absolute diff b/w enantiomers
Impurity
Therapeutically inactive isomer in a racemic mixture
Hyperreactive
people whom an unusually low dose of drug = expected pharmacologic effects
Hypersensitive
ppl allergic (sensitized) to a drug
Hyporeactive
ppl whom require exceptionally large doses of drug to get expected pharmacologic effects
Tolerance
hyporeactivity acquired from chronic exposure to a drug
Cross Tolerance
develops b/w drugs of different classes that produce similar pharmacologic effects (i.e. alcohol & inhaled anesthetics)
Tachyphylaxis
Tolerance that develops acutely w/in a few doses of drug (thiopental)
Cellular Tolerance
the neuronal adaptation that causes tolerance to drugs
Immunity
hyporeactivity d/t formation of antibodies
Idiosyncrasy
unusual effect of drug occurs in small % of ppl regardless of dose administered
Additive Effect
2nd drug acts w/ 1st drug will produce effect = to an algebraic summation
Synergistic Effect
2 drugs interact to give effect greater than algebraic summation
Antagonism
2 drugs interact to produce effect less than algebraic summation
Agonist
vs
Antagonist
drug that activates receptor by binding to that receptor
drug that binds to receptor w/out activating the receptor & also prevents agonist from stimulating receptor
Competitive Antagonism
increasing concentrations of antagonist progressively inhibit the response to unchanging concentration of agonist
Noncompetitive Antagonism
after administration of antagonist, even high concentration of agonist cannot completely overcome the antagonism
Two Compartment Model
drug introduced into central compartment,
distributes to peripheral compartment,
eventually returns to central compartment to be cleared from body
Central Compartment
Intravascular fluid & highly perfused tissues
(kidneys, lungs, heart, brain, liver)
Receive 75% of CO
Plasma Concentration Curve:
logarithm of the < in plasma concentration of drug vs time after rapid IV injection