Pharmacodynamics

Question 0

Agonist

Answer 0

chemical that binds to a receptor and activates the receptor to produce a biological response. Causes an action.
- Full agonist- light is at its brightest

Question 1

Drug-Receptor Interactions

Answer 1

• Most drugs work by binding to receptors
• receptors are located on cell surfaces
• the drug molecule must fit into the receptor (i.e. lock and key)
• drug receptor binding is reversible and selective
• drug- receptor binding is selective
• drugs that bind to receptors may be agonist, partial agonist, or antagonists

Question 2

Partial Agonists

Answer 2

Works like an agonist but only causes partial action

- Think light is dimmed but still shining

Question 3

Antagonists

Answer 3

Blocks action of agonist

• think light is off

Question 4

Inverse Agonists

Answer 4

causes an action opposite to that of the agonist

Question 5

Dose-response relationship/curve

Answer 5

• depicts the relation between the drug dose and magnitude of effect
• the change in effect on an organism (the body) caused by differing levels of exposure (doses) to a stressor (chemical/drug) after a certain exposure time

Question 6

therapeutic index

Answer 6

• minimum toxic concentration minus minimum effective concentration
• comparison of the amount of a therapeutic agent that causes the therapeutic effect to the amount that causes toxicity
• LD50/ED50 EX: 100mg/10mg = 10

Question 7

Onset of action

Answer 7

duration of time it takes for a drug to take effect

Question 8

peak of action

Answer 8

time when drug has peak effect

Question 9

duration of action

Answer 9

length of time drug has effect

Question 10

termination of action

Answer 10

time when drug stops working (“wears off”)

Question 11

Half-life

Answer 11

• Period of time required for the concentration or amount of drug in the body to be reduced by one-half
• A drug’s plasma half-life depends on how quickly the drug is eliminated from the plasma
• 4-5 half life’s to steady state or elimination

Question 12

steady state

Answer 12

occurs when the amount of drug administered (in a given time period) is equal to the amount of drug eliminated in that same period

Question 13

Elimination

Answer 13

drug out of body

Question 14

Bioavailability

Answer 14

% of drug that is absorbed, reaches systemic circulation and is available to reach the largest tissues

• IV 100%
• other routes less

Question 15

Efficacy

Answer 15

Measured by the minimum effect that the drug can achieve

Question 16

Potency

Answer 16

• Compares the doses of two difference drugs that are required to achieve the same effect
• “Potent” = high intrinsic activity at low unit doses