Lecture set 4

Question 1

Drug dose and clinical responses in patients

Answer 1

Time Action Curve
Two important questions for every drug
How quickly is the drug going to act
How long will the drug react
We cannot see toxicity on a Time-action curve

We can know how quickly the drug acts by seeing the onset of effect
We know how long it will react by looking between the MEC for adverse and MEC for desired response which gives us our therapeutic window

Question 2

Quantal vs graded drug response

Answer 2

Quantal
Used to measure all or none responses
It responds to the max or none at all
Ex. take a hypnotic to go to sleep you’re either asleep or you’re not
Binary
Threshold
Minimum effective dose of the drug which evokes an all or none pharmacological response

Graded
Time action curve
Response is graded not all or none
Showing progressively increasing effects
EX heart rate
Center of symmetry which is our ED50

Similarities of Graded and Quantal
Similarities
Sigmoid in nature
Potency and selectivity
Differences
Graded - progressive increases of effect
Quantal - all or none

ED50
The dose required to produce the stated effect in 50% of the population
LD50
The dose required to produce death in 50% of the population
Therapeutic index or ratio
The relative safety of a drug expressed as LD50/ED50
The larger the ratio the greater the relative safety

Question 3

Calculate and compare the therapeutic index between drugs

Answer 3

TI= TD50/ED50 (TD50 also can be LD50)

Question 4

Describe the factors that modify the effects of drugs

Answer 4

Drug tolerance
Condition of decreasing responsiveness
Opioids famous example
Concentration at site of action
Physiological variables
Pathological factors
Genetic factors
Desensitization
biological factors as well
- age
-sex

Question 5

Compare and contrast drug disposition tolerance and pharmacologic tolerance

Answer 5

Drug tolerance
2 ways to develop tolerance
Decrease in effective concentration of the agonist
Drug disposition
Metabolic tolerance
Downregulation of receptors
Change in receptor affinity

Question 6

Apply cross-tolerance to disease management

Answer 6

Tolerance to one drug in a class and occurs with other drugs in a class
EX: tolerance to vicodin means tolerance to morphine

Question 7

Understand the basis for on target and off target adverse effects

Answer 7

?

Question 8

Deconvolute physiological response in multicellular/ multi receptor context