L13-Dynamics of drug action

Question 1

what are the different types of response curves?

Answer 1

A) dose response curve

B) quantal dose response curve

Question 2

what does the dose response curve study?

Answer 2

it studies the efficacy and potency of a drug acting on 1 organ or 1 person only

Question 3

name the substance that gives the same effect as an endogenous ligand

Answer 3

agonist

Question 4

name the drug that gives reduced effect as the endogenous ligand

Answer 4

Partial agonist

Question 5

what is an antagonist?

Answer 5

substance that prevents the response (inhibits it)

Question 6

what type of curve is the dose response curve?

Answer 6

it is a sigmoid curve.

Question 7

what is the Emax of a drug?

Answer 7

it is the maximum response of the drug and if drug concentration increases no further response will occur. it appears as a plateau on the sigmoid curve

Question 8

what is the EC50 of a drug?

Answer 8

its the concentration of the drug that produces half the EMax

Question 9

what happens to the efficacy if the Emax increases

Answer 9

it will increase

Question 10

what will happen to the potency if the EC50 increases?

Answer 10

the potency will decrease

Question 11

what’s the effect of graph shifting to the left on potency?

Answer 11

it will increase the potency.

Question 12

when can potency be compared

Answer 12

when its a drug acting on the same receptor

Question 13

how to know if 2 drugs have the same receptor?

Answer 13

if they have parallel slopes then they are acting on the same receptor

Question 14

what is clinically more important efficancy or potency?

Answer 14

efficancy is clinically more important

Question 15

name the relation between 2 drugs that increase each others potency

Answer 15

potentiation relation

Question 16

name the relation between 2 drugs that decrease the potency of each other

Answer 16

antagonist

Question 17

what is a competitive reversible antagonist?

Answer 17

substance that decreases the potency but gives of the same Emax

Question 18

what is a noncompetitive antagonist ?

Answer 18

something that causes the decrease of efficancy but have the same potency

Question 19

name the relation between 2 drugs that increase the efficancy of each others

Answer 19

synergism or summation

Question 20

what are 2 aspects of the quantal dose response curve?

Answer 20

Therapeutic effect and toxic effect.

Question 21

wha is the ED50?

Answer 21

it is the concentration that gives of half of the maximum therapeutic response

Question 22

what is the TD50?

Answer 22

the concentration that gives of half of the toxic effect

Question 23

what is the safety of the drug?

Answer 23

it is a value to see how safe is the drug. it calculated by {TD50/ED50}. The greater the number the safer the drug is.

Question 24

explain what’s meant by drug tolerance?

Answer 24

it indicates a need to increase the concentration of the drug to maintain the same response.

Question 25

explain what is meant by tachyphylaxis.

Answer 25

it an acute rapidly developed drug tolerance caused by taking the same drug consecutively with quick successions.

Question 26

explain what’s meant by refractoriness.

Answer 26

loss of the therapeutic efficacy of the drug.

Question 27

explain what meant by drug resistance.

Answer 27

signifies the complete loss of effectiveness to antibiotic or anticancer

Question 28

explain what’s meant by idiosyncrasy?

Answer 28

it is an abnormal response to a drug cause by genetic defect

Question 29

explain what is hypersensitivity reaction

Answer 29

when the immune response develops due to the formation of antigen-antibody reaction (ANAPHYLAXIS)

Question 30

explain what’s meant by drug dependance?

Answer 30

an adaptive state that develops due to repeated administration of that drug

Question 31

what are the types of drug dependance?

Answer 31

physical and psychological dependence

Question 32

explain whats meant by physical dependance?

Answer 32

there have been physiological changes and the body has been altered in ways that make it crave that drug. upon cessation the body will experience withdrawal symptoms.

Question 33

explain what meant by psychological dependance

Answer 33

the patient have the urge to take the drug but their body has no change because of it