distribution/elimination (class)

Question 1

how the drug moves around in the body and gets out of the body

Answer 1

distribution

Question 2

diffusibility is a function of the ? where solubility is a function of the?

Answer 2

membrane, drug

Question 3

for a drug to move around fast and efficiently you need high?

Answer 3

diffusibility and solubility

Question 4

3 things that determine a drugs concentration

Answer 4

1. body vs SOA
2. duration (how long its in the body)
3. Elimination

Question 5

path through the cell membrane?

Answer 5

stomach –> intestine –> blood stream

Question 6

what type of molecules will exit the stomach quickly?

Answer 6

small lipid soluble ones

Question 7

problem with high solubility?

Answer 7

high solubility results in drug molecules aggregating outside the CNS= side effects

Question 8

3 characteristics of drugs in the CNS

Answer 8

1. no discriminability (cant decide where most of the drug goes)
2. less “potents” in the CNS
3. longer lasting/ annulled effects (annulled because the clean up crew comes in)

Question 9

why are drugs less “potent” in the CNS

Answer 9

(need less of the drug in the body for the brain to be affected than any other organ , brain is more sensitive)
- the minute you diffuse a drug it will get into the liver before the brain, but you need less of a drug to effect the brain than the liver

Question 10

capillaries are part of the ? system and allow for the transmission of?

Answer 10

vascular, nutrients

Question 11

the tightly packed cells of the capillaries allow for? (2)

Answer 11

1. minimal transmission across the membrane

2. blood flow affects molecule exit

Question 12

how does blood flow effect distribution?

Answer 12

the more blood flow the organ receives the more drug it will get

Question 13

2 types of diffusion through the blood- brain barrier

Answer 13

1. active diffusion (ion pump)

2. passive diffusion (transport protein)

Question 14

active diffusion is a function of the ? where passive diffusion is a function of ?

Answer 14

• body

- drug molecule

Question 15

passive transport through the BBB is still active for the ? but passive for the ?

Answer 15

active for the brain

passive for the drug

Question 16

with passive diffusion, the function of the drug molecule depends on (3)

Answer 16

1. lipid solubility
2. small/ simple chains
3. uncharged (not an ion)
   - -> can only be ionized after it attaches

Question 17

the placental barrier is a semi permeable membrane (why?)

Answer 17

the barrier just slows down the rate chemical gets through

–> doe snot stop it

Question 18

what do maternal blood vessels and blood, fetus capillaries do?

Answer 18

controls the RATE of exchange

Question 19

2 factors of controlling the rate of exchange in fetus capillaries

Answer 19

1. osmotic principles

2. 75-100% of maternal drug in 5 minutes

Question 20

membrane diffusibility of the placenta will have different effects depending on what?

Answer 20

gestation stage

Question 21

elimination is dependent on?

Answer 21

intake method

Question 22

what organ is ALWAYS involved in elimination?

Answer 22

the kidney

Question 23

organs involved in oral elimination?

Answer 23

liver, kidney

Question 24

organs involved in parenteral elimination?

Answer 24

kidney

Question 25

organs involved in absorption elimination?

Answer 25

kidney

Question 26

organs involved in inhalation elimination?

Answer 26

lung, kidney

Question 27

what does the liver do?

Answer 27

breaks down drugs in the system and produces the chemicals we need to do so

Question 28

the liver takes part in ? (2)

Answer 28

1. enzyme proliferation

2. “first pass” metabolism

Question 29

when ppl are tolerant it has to do with? and more of this =

Answer 29

enzymes, more enzymes= less likely the drug will reach SOA

Question 30

what is “first pass” metabolism

Answer 30

anything that goes mouth, stomach, intestine and out

Question 31

second pass metabolism is?

Answer 31

anything that goes into the blood stream

Question 32

3 characteristics of first pass metabolism and the liver

Answer 32

1. drug conc is reduced before reaching SOA
2. metabolites can be more or less effective than the parent
3. excreted (metabolites that are toxins.

Question 33

what are metabolites?

Answer 33

whats left after the drug is broken down

Question 34

what metabolism is responsible for side effects

Answer 34

first pass metabolism

Question 35

elimination is dependent on ?

Answer 35

toxicity of metabolites

characteristics of the drugs not the body

Question 36

high toxicity= ? order reaction

low toxicity= ? order reaction

Answer 36

• zero

- first

Question 37

what is zero order reaction

Answer 37

rate of elimination is constant

Question 38

what is first order reaction

Answer 38

half life elimination

Question 39

an overdose results in what type of elimination

Answer 39

zero order

Question 40

an urinalysis tests for? and a blood sample tests for?

Answer 40

• metabolites

- drug

Question 41

4 problems with drug testing

Answer 41

1. detection time < elimination time (drug sample = 48 hours,. urinalysis = 24 hours)
2. length of drug use
3. individual differences (body comp)
4. negative results dont necessarily confirm non- use

Question 42

why do negative results not always mean they are drug free?

Answer 42

other drugs can interfere (birth control) and genetics (hair colour)

Question 43

3 characteristics of false negative test

Answer 43

1. substitution
2. adulteration
3. dilution

Question 44

2 other methods of drug testing

Answer 44

1. hair analysis (higher detection period, 90days)

2. oral fluid testing (vulnerable to tampering)

Question 45

what is a watershed area?

Answer 45

An area where two arteries meet, where blood supply is decreased (border-zone)

Question 46

what is an example of a watershed area?

Answer 46

internal carotid artery

anterior and middle cerebral artery

Question 47

carotid artery is extremely dangerous due to?

Answer 47

clotting, changes in BP. bleeding