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Pharmacology 2100 > Pharmacokinetics > Flashcards

Flashcards in Pharmacokinetics Deck (43):
1

what does ADME stand for

absorb
distributes
metabolize
eliminate

2

what determines the intensity of the drugs effect

the concentration at the site of the receptor

3

what are the routes of administration

oral
IV
subcutaneous
intramuscular
transdermal pathc
rectal
inhalation
sublingual

4

3 ways drugs cross the cell membrane

pass through channels or pores
through membrane with transport system
penetrate directly if lipophilic (most common)

5

where are transporters found

liver
kidney
intestine
brain capillaries

6

how is 2 compartment model different from one compartment

in two drugs are not distributed instantaneously to peripheral, there is a time lag

7

what kinds of drugs are best described by one compartment model

drugs that dont extensively distribute into extravascular tissues

8

what is another word for bioavailability

absorption

9

describe bioavailability

fraction of unchanged drug that reaches the blood

10

what is drug accumulation

inversly proportional to dose lost

11

describe volume of distribution

how drug is distributed in body relative to plasma

12

define clearance

ability of the body to eliminate the drug

13

what is the drug half life

time required to change the amount of drug in the body by one half

14

what does AUC stand for

the area under the curve of a graph of plasma concentration against time

15

what is the % bioavailability in IV admin

100%

16

what is the first pass effect

drugs metabolized and inactivated in the liver

17

describe enterophepatic cycling

body recycles the drug from liver to bile duct back into the intestine, hepatic artery, liver again
prolongs half life

18

8 factors that influence drug absorption

fromulation
water solubility
lipid solubility
pka
Gi motility
posture
others drugs/food
gastric ph

19

is the drug charged or uncharged when passing through a membrane?

uncharged

20

acidic drugs require what environment to pass through the membrane

acidic environment so they are in the uncharged HA form (dont ionize in acidic)

21

basic drugs require what environment to pass through the membrane

alkaline environment so it is in the uncharged form B (dont ionize in basic)

22

how many half lives does it take for a drug to be fully accumulated or eliminated

4

23

what is steady state

when rate of drug elimination equals rate of administration

24

what does a high volume of distribution represent

drug is extensively distributed and not in the plasma

25

what is the loading dose

Vd x desired plasma concentration

26

how do you calculate volume of distribution

total amount of drug in body/ plasma concentration

27

what is th epurpose of the loading dose

reach therapeutic range right away

28

what are the phase 1 reactions

oxidation
reduction
hydrolysis

29

what are the phase 2 reactions

glucuronidation
sulfation
acetylation

30

what is the result after phase 1 reactions in metabolism

usually an inactive metabolite by adding or exposing a polar group

31

what is the result of phase 2 reactions

a conjugated derivative

32

what is first order metabolism

rate of drug metabolism proportional to dose

33

what is zero irder metabolism

enzyme is saturated and the rate of drug metabolism remains constant overtime

34

what are 6 consequences of phase 1 +2 metabolism

accelerated renal excretion
drug inactivation
activation of prodrugs
decreased toxicity
increased therapeutic action
increased toxicity

35

define clearance

volume of plasma that must lose all the drug it contains in one minute to account for the observed rate of drug elimination

36

how many half lives are required to eliminate a single dose of a drug from the body

4-5

37

what is the importance of clearance

tells efficiency by which a drug is removed from the body
determining maintenance dose and dosing rate

38

what type of drugs are excreted in urine

non lipid soluble
polar
ionized
low MW

39

how does aging affect half life (decreased muscle)

decreases half life

40

how does obesity effect half life

increases

41

how does pathologic fluid effect half life

increases

42

how does induction of cyp450 affect half life?
inhibition?

induction decreases
inhibition increases

43

how does organ failure effect half life

increases