Intro to pharmacology/pharmokinetics/pharmodynamics

Question 1

Dose

Answer 1

amount of drug administered in a given formulation

Question 2

response is proportional to?

Answer 2

of receptors occupied by the drug, but not always a linear relationship

Question 3

response affected by?

Answer 3

affinity and receptor signal transmission

Question 4

curves represent what?

Answer 4

dosage over which the drug is effective and peak effect/response that can be expected.

Question 5

shape of curve and plateau indicate what?

Answer 5

info regarding binding of drug to cellular receptors

Question 6

threshold dose

Answer 6

where response begins and increases in magnitude until a response plateau is reached

Question 7

ceiling effect ( maximal efficacy)

Answer 7

point at which there is no further response (even if dosage continues to be increased)

Question 8

potency

Answer 8

threshold dose that produces a given response

Question 9

what does higher potency mean?

Answer 9

less of the compound is required to produce given response

Question 10

efficacy

Answer 10

dose ranges over which the drug has desired effect

Question 11

what happens to magnitude of response?

Answer 11

increases as dosage increases

Question 12

First Pass Effect

Answer 12

…

Question 13

What is first pass effect?

Answer 13

metabolism/destruction of drug molecule in liver before reaching its site of action

Question 14

What medications endure first pass effect?

Answer 14

Enteral/oral meds

Question 15

What meds. bypass first pass?

Answer 15

Para-enternal meds. bypass GI system and take a more direct route to target site

Question 16

Bioavailability

Answer 16

…

Question 17

what is bioavailability?

Answer 17

% of drug administered that reaches the bloodstream

Question 18

What does bioavailability depend on?

Answer 18

route of administration and drugs ability to cross membrane barriers

Question 19

Volume of distribution

Answer 19

…

Question 20

What is volume of distribution?

Answer 20

amount of drug administered divided by concentration of drug in plasma

Question 21

Vd = total body H20

Answer 21

uniform body distribution

Question 22

Vd> total body H20

Answer 22

drug is being concentrated in tissues

Question 23

Vd

Answer 23

drug is being retained in bloodstream

Question 24

Distribution?

Answer 24

moving the drug throughout the body

Question 25

What does distribution depend on? -4

Answer 25

1. tissue permeability 2. blood flow 3. plasma protein binding 4. sub cellular protein binding

Question 26

Tissue permeability

Answer 26

highly lipid soluble molecules cross membranes more easliy

Question 27

blood flow

Answer 27

bloodstream carries drugs to highly perfused organs, can be affected by disease

Question 28

what does negative venule pressure due?

Answer 28

pulls drug from tissues back into blood

Question 29

what does positive arteriole pressure do?

Answer 29

draws drug via blood into tissue spaces

Question 30

what is plasma protein binding?

Answer 30

reversible bonds | -bound portion of drug doesn't have a therapeutic effect and is not eliminated

Question 31

what is an inactive drug?

Answer 31

bound in plasma protein and cannot leave blood to distribute into tissues

Question 32

what is active?

Answer 32

unbound and can distribute to tissues

Question 33

what is sub cellular protein binding?

Answer 33

drug gets trapped within the cell (lysosome) | ex. Anti depressants

Question 34

How are drugs metabolized and eliminated?

Answer 34

...

Question 35

metabolism

Answer 35

1. primarily in liver | 2. also in lungs, kidneys, Gi, skin

Question 36

factors affecting metabolism?

Answer 36

tissue/organ damage, metabolic inhibitors, enzyme induction

Question 37

competitive inhibition?

Answer 37

inhibition of enzyme that metabolizes drub B by drug A | - decreases metabolism of drug B

Question 38

irreversible inhibition of metabolism?

Answer 38

Inhibition of the enzyme that metabolizes drug B by drug A - decreases metabolism of drug B - covalent bonding of inhibitor

Question 39

induction of metabolism

Answer 39

induction of the enzyme that metabolizes drub B by drug A | -increases the metabolism of drug B by increasing the enzyme quantity

Question 40

Elimination

Answer 40

...

Question 41

What is biotransformation (metabolism)?

Answer 41

Chemical altering of a drug to metabolite via enzymes to deactivate that drug

Question 42

oxidation

Answer 42

usual method via endoplasmic smooth reticulum via enzymes O & H Phase I reaction

Question 43

Reduction

Answer 43

happens in cell via cytoplasm | phase I reaction

Question 44

Hydrolysis

Answer 44

original compound is broken into separate parts via enzymes | phase I

Question 45

Conjugation

Answer 45

drug or metabolite bi product of one or other mechanisms

Question 46

Excretion

Answer 46

eliminating active form of drug

Question 47

where does it occur?

Answer 47

kidneys

Question 48

factors affecting excretion?

Answer 48

reabsorption polarity of metabolite polar (ionized) drugs tend to be excreted non polar tend to be reabsorbed

Question 49

what is clearance?

Answer 49

ability of organs to clear drug | dependent on perfusion

Question 50

factors that affect clearance?

Answer 50

blood flow to organ extraction ratio - fraction of drug removed from plasma as it passes through organ concentration

Question 51

half life

Answer 51

duration of activity of the compound in body | amount of time required for 50% of the drug remaining in body to be eliminated

Question 52

what is half life a function of?

Answer 52

clearance and Vd | volume of distribution

Question 53

Drug administration - oral vs. transdermal

Answer 53

...

Question 54

oral

Answer 54

``` enteral easiest to self administer absorbed by small intestine -must have high lipid solubility -undergoes first pass effect ```

Question 55

disadvantages of oral?

Answer 55

limited or erratic absorption of some drugs

Question 56

transdermal?

Answer 56

bypasses GI system and first pass effect. takes more direct route to target site more predictable quantity

Question 57

disadvantage of transdermal?

Answer 57

drug must be able to pass through intact dermal layers | ex. injection, IV, Sub-q

Question 58

continuous administration

Answer 58

matching the rate of administration with the rate of drug elimination once desired plasma concentration is achieved

Question 59

interval administration

Answer 59

dosage is adjusted to provide an average plasma concentration over the dosing period

Question 60

what does dosing interval (time in hours) do ?

Answer 60

affects size of dosage needed to maintain same relative plasma concentration