intro to pharmokinetics and ADME

Question 1

What does pharmacological effect depend upon?

Answer 1

affinity

intrinsic efficacy -relative ability of a drug-receptor complex to produce a maximum functional response

residence time-

Question 2

What is pharmacodynamics?

Answer 2

what the drug does to the body

Question 3

What is ADME?

Answer 3

Pharmacokinetics, or “what the body does to the drug”

Absorption
Distribution
Metabolism
Excretion

Question 4

What is biophase?

Answer 4

the effect site of the drug (the physical region in which the
drug target is located)

Question 5

What is bioavailibility?

Answer 5

The extent and rate at which the drug reaches it site of action

Question 6

What does more drug in plasma lead to?

Answer 6

more will get to site of action

Question 7

Where are enzymes that could break down drugs before make it into circulation?

Answer 7

liver and gut

Question 8

What is C max?

Answer 8

plasma concentration

Question 9

What is the therapeutic index?

Answer 9

ratio of the largest non toxic dose to the minimum effective dose

Question 10

Where do the drugs go from the plasma?

Answer 10

plasma to interstitial fluid (drugs have to get out of capillary bed)
interstitial and then to intracellular (must cross cell membrane)

Question 11

What would a partition coefficent mean?

Answer 11

1- equally distributed higher than 1 - more soluble in oil than water

Question 12

What solubility is the unionised form of drug?

Answer 12

unionised form

Question 13

Describe acids and bases will be ionised at diff pH?

Answer 13

weak acids- ionised at low pH
weak bases- least ionised at high pH

Question 14

What can excessive ionisation within a particular compartment lead to?

Answer 14

drug becoming trapped

Question 15

What does the maximum concentration achieved within the tissue depend on?

Answer 15

firstly on the plasma concentration of the drug
and
how quickly it can get into tissue and how quick removed

Question 16

Describe the three compartment body?

Answer 16

the central compartment (plasma) will drive distribution to tissues.
Other two compartments are rapidly equilibriated tissues such as muscle (highly perfused) and then rest are slowly equilibriating such as adipose.

Question 17

What happens if plasma concentration drops lower than that of tissues?

Answer 17

drug moves back into plasma

Question 18

What would make the plasma concentration drop lower than the tissue concentration?

Answer 18

happens because of metabolism and excretion

Question 19

What is a portal circulation?

Answer 19

Capillary bed drains directly into another capillary bed

Question 20

What is the idea of metabolism?

Answer 20

To make the metabolite (drugs) more polar than the parent compound and thus more easily excreted

Question 21

What are the phases of metabolism?

Answer 21

phase 1 - functional group added as a handle
phase 2 -larger group added

Question 22

Describe importance of liver?

Answer 22

main site of metabolism
many drugs excreted in bile