Drug Action

Question 1

what is pharmacodynamics?

Answer 1

what a drug does to the body

Question 2

what is pharmacokinetics?

Answer 2

what the body does to a drug

Question 3

what is a drug?

Answer 3

any substances of a known structure used in treatment, prevention or diagnosis of a disease

Question 4

what is a medicine?

Answer 4

a chemical preparation containing one or more drug with the intention of a therapeutic effect

Question 5

what is selectivity?

Answer 5

the ability of a drug to distinguish between different molecular targets with the body

Question 6

what does selectivity allow drugs to do?

Answer 6

interact with select cells and tissues to produce their intended effect, by binding to their specific targets

Question 7

name some potential targets drugs can have in the body

Answer 7

enzymes 
carrier molecules 
ion channels 
receptors 
RNA/DNA

Question 8

what is an agonist?

Answer 8

a drug that binds to a receptor to produce a cellular response

Question 9

what is an antagonist?

Answer 9

a drug that reduces/blocks the action of an agonist by binding to the same receptor

Question 10

what features do agonists possess?

Answer 10

affinity

efficacy

Question 11

what is affinity?

Answer 11

the strength of association between ligand and receptors

Question 12

what does it mean if a receptor has low affinity?

Answer 12

fast dissociation rate

equilibrium favours reactants

Question 13

what does it mean if a receptor has medium affinity?

Answer 13

moderate dissociation rate

equilibrium balanced

Question 14

what does it mean if a receptor has high affinity?

Answer 14

slow dissociation rate

equilibrium favours products

Question 15

what is efficacy?

Answer 15

the ability of an agonist to evoke a cellular response

Question 16

what does it mean if an agonist has low efficacy?

Answer 16

smaller response

Question 17

what does it mean if an agonist has high efficacy?

Answer 17

larger response

Question 18

what features do antagonists possess?

Answer 18

affinity

lack efficacyd

Question 19

describe the relationship between agonist concentration and receptor occupancy

Answer 19

as agonist concentration increases, receptor occupancy increases

hyperbolic relationship on a graph

Question 20

what is EC50?

Answer 20

the concentration of agonist that elicits a half maximal effect

Question 21

how can reversible competitive antagonism be overcome?

Answer 21

increasing the concentration of the agonist