Principles

Question 1

pharmacokinetics

Answer 1

relationship between drug dosing and [ ] in fluids, tissues and time

Question 2

Absorption

Answer 2

drug moving from the site of administration to blood

Question 3

Bioavailability

Answer 3

% of drug administered that reaches systemic circulation

• all oral drugs undergo 1st pass through liver
• sublingual drugs go into SVC and bypass 1st pass
• IV drugs are 100% bioavailable

Question 4

Distribution

Answer 4

achieved by the blood stream throughout the body

Question 5

Law of Mass Action

Answer 5

drugs follow mass action
high[plasma] = moves into the tissues
high[tissue] = moves into plasma

Question 6

Major determinant of end organ drug concentration?

Answer 6

the rate of rise in [ ] = determined by organ perfusion and relative solubility

Question 7

free vs bound molecules

Answer 7

as free molecules move into tissues -> they are immediately replaced by new unbound molecules that were bound before

Question 8

lipophilic molecules

Answer 8

they readily transfer between the blood and organs

Question 9

Context Sensitive half time

Answer 9

time for a 50% decrease of a [drug] after an infusion in stopped

Question 10

Volume of Distribution

Answer 10

Vd = bolus dose/concentration

Question 11

Biotransformation

Answer 11

chemical process by which drug molecule is altered in the body
- primarily liver metabolism except for esters

Question 12

Phase I

Answer 12

oxidation, reduction, hydrolysis

Question 13

Phase II

Answer 13

conjugation w/ endogenous substrates

Question 14

Excretion

Answer 14

most are renally cleared

- RBF x renal extraction

Question 15

Pharmacodynamics

Answer 15

study of how drugs affect the body

Question 16

Exposure-Response relationship

Answer 16

as body is exposed to increasing doses = the response similarly increases

Question 17

sigmoidal dose-response curve

Answer 17

baseline = minimum threshold
slope = increasing response to increasing dose
asymptote = maximal response threshold