L1 Pharmacodynamics

Question 1

What is pharmacodynamics?

Answer 1

What drugs do to the body

Question 2

What is pharmacokinetics?

Answer 2

What the body does to drugs

Question 3

What is pharmacogenomics?

Answer 3

Study of the genetic variations that cause differences in how individuals respond to drugs

Question 4

What is an agonist?

Answer 4

Binds to the receptor and initiates a response that can be full or partil

Question 5

What is an antagonist

Answer 5

Binds to the receptor but does NOT initiate a response

Question 6

What are allosteric activators and inhibitors?

Answer 6

Bind to a site OTHER than the active site and alter response

Question 7

What is responsible for drug specificvit?

Answer 7

The receptor

Question 8

What determines the quantitative relationship between drug concentration and pharmacological effect?

Answer 8

The receptor

Question 9

Can a receptor respond to multiple shapes and charges?

Answer 9

No, the interaction between a drug and receptor is very specific. Only a specific shape and chemical charge will fit

Question 10

Is ionic/electrostatic interaction reversible?

Answer 10

Yes

Question 11

Is covalent binding reversible?

Answer 11

NO

Question 12

What is an example of drugs that do hydrophobic interactions?

Answer 12

Lipid soluble drugs like local anesthetics and anticonvulsants

Question 13

What is this type of interaction:

Nonpolar region of a drug binds to a non-polar region of the receptor

Answer 13

Hydrophobic interaction

Question 14

What is this kind of interaction:

Atoms from two molecules share electrons

Answer 14

Covalent binding

Question 15

What is the classic example of a drug that binds covalently and irreversibly?

Answer 15

Aspirin binding to the COX enzyme

Question 16

Are drugs constantly binding and unbinding from their receptors?

Answer 16

YES unless it’s covalently bound

Question 17

What is “the ability of a drug to bind to a receptor”

Answer 17

Affinity

Question 18

At equilibrium, how many of the receptors are bound?

Answer 18

Half

Question 19

What is Kd

Answer 19

The concentration of free drug at which 50% of the drug is bound to its receptor

Question 20

What is the other name for “equilibrium dissociation constant”

Answer 20

Kd

Question 21

What does Kd measure?

Answer 21

The affinity

Question 22

What kind of drug has affinity and intrinsic activity?

Answer 22

Full agonists

Alpha=1

Question 23

What is efficacy/intrinsic activity?

Answer 23

The ability of a drug to initiate a response

Question 24

What kind of drug has affinity but no intrinsic activity?

Answer 24

Antagonists

Alpha=0

Question 25

What is Emax?

Answer 25

The maximal response

Question 26

Are efficacy and potency related in any way?

Answer 26

NO Just because you have a maximum effect doesn’t mean you have a potent drug, it could just be that you have a lot of it

Question 27

What is EC50

Answer 27

The plasma concentration of the drug that produces 50% of the maximal effect

Question 28

If EC50 is low, what does that say about the potency of the drug?

Answer 28

Lower the EC50, the more potent the drug

Question 29

What is ED50

Answer 29

The dose with 50% maximal effect Goes hand in hand with EC50

Question 30

Why do we use a semi log scale when making a dose response curve?

Answer 30

It expands the scale at low concentrations where the response increases rapidly (therapeutic effect), and it contracts at high concentrations where response is not changing as quickly (toxicity)

Question 31

What can we calculate by using a semi log plot of a dose response curve?

Answer 31

Kd and EC50/ED50

Question 32

What is potency?

Answer 32

The dose required to produce a given effect

Question 33

What does a graded dose response curve measure

Answer 33

The response in an individual

Question 34

What does a steep slope mean on a graded dose response curve?

Answer 34

The drug has a small therapeutic window (risky)

Question 35

What does a quantal dose-respond curve tell you?

Answer 35

The frequency within a population that a response occurs

Question 36

What can we calculate from a quantal dose-respond curve?

Answer 36

ED50 LD50 TD50

Question 37

What is the therapeutic ratio/index/window? | Not calculation

Answer 37

The range of doses with high efficacy and low probability of adverse effects

Question 38

How do you calculate the therapeutic ratio/index/window

Answer 38

TR=LD50/ED50 | So if TR=4, then you can multiply ED50 by 4 and still be pretty safe?

Question 39

How do you calculate the margin of safety?

Answer 39

Margin of safety= LD1/ED99

Question 40

The higher the margin of safety the ______ the drug

Answer 40

Safer

Question 41

A margin of safety that is less than 1 means:

Answer 41

It is a very risky drug

Question 42

Are efficacy and intrinsic activity the same thing?

Answer 42

YES

Question 43

If a tissue type has lots of spare receptors, how do you adjust the dose?

Answer 43

LOWER the dose

Question 44

What does it mean if you can elicit a maximum response without occupying all the available receptors?

Answer 44

The tissue has Spare receptors

Question 45

If a tissue has spare receptors, how will EC50 relate to Kd

Answer 45

EC50 will be lower than Kd | You got 50% maximal effect by binding fewer receptors

Question 46

What happens to the concentration response curve (EC50) if there are spare receptors?

Answer 46

It is shifted to the left

Question 47

What happens to Kd if there are spare receptors?

Answer 47

NOTHING

Question 48

If EC50 is lower than Kd, then_____

Answer 48

There are spare receptors and you need to use a lower dose