Chapter 5 - Pharmacodynamics

Question 1

Pharmacodynamics

Answer 1

How the drugs exerts its effect on the body; how the medicine changes the body

Question 2

Therapeutic index

Answer 2

Measure of a drug’s safety margin; the higher the value, the safer the drug

Question 3

Interpatient variability in response to drugs can best be understood by examining a …

Answer 3

Frequency distribution curve

Question 4

Frequency distribution curve example-

Answer 4

Response desired is a reduction of 20mmHg in systolic bp

Few patients only need 10 mg of drug to reach this, but a 50mg dose gave a larger number of patients this level and a few needed as much as 90mg dose to reach a 20mmHg reduction

Question 5

The — the therapeutic index the — the drug.

Answer 5

Higher, safer

Question 6

Dose response relationship

Answer 6

Phase 1 - low doses; the flat line of the graph indicates that few target cells have been affected by the drug

Phase 2 - giving more drug results in more effect; and lowering drug dose gives less effect

Phase 3 - plateau; more of a drug will not produce further therapeutic effects, potentially toxic

Question 7

Drug that produces the same type of response as the endogenous substance

Answer 7

Agonist

Question 8

Example of agonist drug

Answer 8

Heroin - full opiate agonist

Question 9

Antagonist drug

Answer 9

Bind to and occupy receptor to prevent endogenous chemical from binding; compete with agonist for the receptor!

Narcan is an example of an antagonist; binding to opioids receptors without acting on them

Question 10

Partial agonist

Answer 10

Produce a weaker, less effective response than a full agonist

Suboxone is a partial agonist