The dose-response relationship

Question 1

What is pharmacology

Answer 1

the branch of medicine and biology concerned with the study of drug action

Question 2

What is an agonist

Answer 2

A drug or endogenous hormone that occupies and activates a receptor to produce a biological response

Question 3

What is a drug (2)

Answer 3

1. A substance that causes a change in the biological functions of cells and tissues through its actions
2. The majority of drugs work on receptors

Question 4

What is affinity

Answer 4

the tendency of the drug/hormone to bind to the receptor to form a Drug-Receptor Complex

Question 5

What is efficacy/intrinsic activity

Answer 5

the ability of the drug to trigger a pharmacological response after forming a Drug-Receptor Complex

Question 6

What effect does a full agonist have on affinity and intrinsic activity

Answer 6

High Affinity & High Intrinsic Activity

Question 7

What effect does a partial agonist have on affinity and intrinsic activity (3)

Answer 7

1. Low Affinity & High Intrinsic Activity
2. High Affinity & Low Intrinsic Activity
3. Low Affinity & Low Intrinsic Activity

Question 8

What effect does an antagonist have on affinity and intrinsic activity

Answer 8

High Affinity & No Intrinsic Activity

Question 9

What is the receptor theory

Answer 9

The magnitude of the biological response to a drug (agonist) is proportional to the number of drug-receptor interactions that occur

Question 10

What is the dose-response relationship (2)

Answer 10

1. As a dose increases, the concentration of drug able to interact with the receptor increases
2. the maximum biological response occurs when all receptors that can be occupied are occupied by a drug

Question 11

What is drug efficacy (2)

Answer 11

1. Maximum response a drug can produce
2. Emax

Question 12

What is drug potency (3)

Answer 12

1. Measure of drug needed for a biological response
2. Half the maximum biological response
3. ED50

Question 13

What effect do partial agonists have on Emax

Answer 13

Produces biological response but not 100% of it even at high doses

Question 14

What impact do agonists have on receptor activity

Answer 14

has independent impact on receptor activity

Question 15

What impact do antagonists have on receptor activity

Answer 15

impacts receptor activity in the presence of agonist

Question 16

What impact do inverse agonists have on receptor activity (2)

Answer 16

1. Independent impact on receptor activity
2. Produces opposite effect to agonist

Question 17

What is an antagonist

Answer 17

A drug that occupies a receptor but does NOT produce a biological response (may block or hinder the action of agonists)

Question 18

What are the 2 types of antagonists (2)

Answer 18

1. Competitive (reversible)
2. Non-competitive (irreversible)

Question 19

How do competitive antagonists work (2)

Answer 19

1. Compete with agonists for the same receptor
2. Make agonists look less potent

Question 20

How do non-competitive antagonists work (3)

Answer 20

1. Bind to receptors permanently (covalent)
   or
2. Block the agonist binding site
3. Reduce Emax that an agonist can produce

Question 21

What is the therapeutic index (3)

Answer 21

1. Measure of drug safety
2. higher therapuetic index is safet than low
3. LD50 is the dose that kills 50% of animals receiving it (lethal dose )

Question 22

What are examples of drugs with a low therapeutic index (3)

Answer 22

1. Lithium
2. Digoxin
3. Warfarin

Question 23

What does it mean if a drug is more potent than the other (2)

Answer 23

1. The drug has a lower ED50
2. meaning less drug is needed to reach half Emax than the other