Intro Topics

Question 1

Pharmacokinetics

Answer 1

Quantitative study of the
absorption, distribution, metabolism, excretion of injected/inhaled drugs & their metabolites

What body does to drug

Question 2

Pharmacodynamics

Answer 2

study of intrinsic sensitivity (responsiveness) of receptors to a drug & mechanisms by which these effects occur

What drug does to body

Question 3

Chirality & Enantiomers

Answer 3

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)

Question 4

Racemic Mixture

Answer 4

2 enantiomers present in equal proportions

-Don’t rotate polarized light

Question 5

Stereoselective vs Stereospecific

Answer 5

Stereoselective: relative difference b/w enantiomers
Stereospecific: absolute diff b/w enantiomers

Question 6

Impurity

Answer 6

Therapeutically inactive isomer in a racemic mixture

Question 7

Hyperreactive

Answer 7

people whom an unusually low dose of drug = expected pharmacologic effects

Question 8

Hypersensitive

Answer 8

ppl allergic (sensitized) to a drug

Question 9

Hyporeactive

Answer 9

ppl whom require exceptionally large doses of drug to get expected pharmacologic effects

Question 10

Tolerance

Answer 10

hyporeactivity acquired from chronic exposure to a drug

Question 11

Cross Tolerance

Answer 11

develops b/w drugs of different classes that produce similar pharmacologic effects (i.e. alcohol & inhaled anesthetics)

Question 12

Tachyphylaxis

Answer 12

Tolerance that develops acutely w/in a few doses of drug (thiopental)

Question 13

Cellular Tolerance

Answer 13

the neuronal adaptation that causes tolerance to drugs

Question 14

Immunity

Answer 14

hyporeactivity d/t formation of antibodies

Question 15

Idiosyncrasy

Answer 15

unusual effect of drug occurs in small % of ppl regardless of dose administered

Question 16

Additive Effect

Answer 16

2nd drug acts w/ 1st drug will produce effect = to an algebraic summation

Question 17

Synergistic Effect

Answer 17

2 drugs interact to give effect greater than algebraic summation

Question 18

Antagonism

Answer 18

2 drugs interact to produce effect less than algebraic summation

Question 19

Agonist
vs
Antagonist

Answer 19

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

Question 20

Competitive Antagonism

Answer 20

increasing concentrations of antagonist progressively inhibit the response to unchanging concentration of agonist

Question 21

Noncompetitive Antagonism

Answer 21

after administration of antagonist, even high concentration of agonist cannot completely overcome the antagonism

Question 22

Two Compartment Model

Answer 22

drug introduced into central compartment,
distributes to peripheral compartment,
eventually returns to central compartment to be cleared from body

Question 23

Central Compartment

Answer 23

Intravascular fluid & highly perfused tissues
(kidneys, lungs, heart, brain, liver)
Receive 75% of CO

Question 24

Plasma Concentration Curve:

Answer 24

logarithm of the < in plasma concentration of drug vs time after rapid IV injection

Question 25

distribution (alpha) & elimination (beta) phase

Answer 25

Distribution Phase: begin immediately after IV injection; reflect drug’s distribution from circulation (central compartment) to peripheral tissues (peripheral compartment)

Elimination Phase: gradual decline in plasma concentration of drug; reflects drug’s elimination from central compartment/ circulation by renal & hepatic clearance mechanisms

Question 26

Elimination Half-Time

Answer 26

time necessary for plasma concentration of a drug to decrease by 50% during elimination phase

Directly Proportional to Vd
Inversely proportional to clearnace
Independent of dose administered

Question 27

Elimination Half Life

Answer 27

time to eliminate 50% of drug from body after rapid IV injection

*Half-life & half time are not equal if decrease in plasma concentration doesn’t parallel its elimination from the body

Question 28

Steady state plasma concentration

Answer 28

Time to achieve steady state plasma concentration (Cpss) w/ intermittent dosing ~ 5 elimination half times

Question 29

Half Time relationship to Drug Eliminated

Answer 29

1/2 Times Fraction of initial left % Eliminated
0 1 0
1 1/2 50
2 1/4 75
3 . 1/8 87.5
4 1/16 93.8
5 1/32 96.9
6 1/64 98.4

Question 30

Context Sensitive Half Life

Answer 30

time necessary for plasma drug concentration to decrease by 50% after stopping continuous infusion of specific duration
considers: metabolism, distribution, duration of infusion

Question 31

Time to recovery

Answer 31

Depends on how far the plasma concentration of drug must < to reach level compatible w/ awakening

Question 32

Biophase

Answer 32

Effect Site of a drug

Question 33

Effect-Site Equilibrium time

Answer 33

half time of equilibrium b/w drug plasma concentration and drug effect

Timing of IV administration: short ESE time = rapid onset

Question 34

Oral Administration of Drug

Answer 34

Convenient and economic route
DIsadvantages: emesis, destruction of drug, Irregularities in absoprtion
Onset of drug effect determined by rate and extent of absorption from GI tract (principle site small intestine)

Question 35

First Pass Hepatic Effect

Answer 35

drug absorbed by GI tract –> portal venous blood –> liver (before entering systemic circulation for delivery to tissues)

Extensive hepatic extraction & metabolism = >diff b/w oral & IV effects

Question 36

Oral Transmucosal Administration

Answer 36

sublingual or buccal, rapid onset bc it bypasses liver,

venous drainage from sublingual area is into superior vena cava

Question 37

Transdermal Administration

Answer 37

provides sustained therapeutic plasma concentrations, less complex than cont IV infusions, low incidence of side effects

7 days of adhesion duration limit
absorbed into sweat ducts & hair follicles,
rate limiting step is diffusion across stratum corneum of epidermis

Question 38

Rectal administration

Answer 38

if given in proximal rectum- absorbed into superior hemorrhoidal veins and transported to liver via portal venous system
(= 1st pass hepatic effect)

low rectal administration go into systemic circulation 1st

Question 39

diffusible fraction of drug

Answer 39

nonionized, lipid soluble, unbound to protein

Question 40

Body Tissue Composition/ Blood Flow

Answer 40

% of Mass .    %CO
Vessel rich            10            75
Muscle                  50            19
Fat                         20            6
Vessel Poor           20          <1

Question 41

1st Pass Pulmonary Uptake

Answer 41

influence peak arterial concentration of drug

Serve as reservoir

Question 42

Plasma Cholinesterase Deficiency

Answer 42

Chromosome 3

Autosomal recessive

Caucasian pop highest prevalence (4%)

5-60min apnea (1/3000 >1hr