admin. and elim.

Question 1

define bioavailability

Answer 1

how much of a drug gets through the liver to get an active response

Question 2

how long does oral administration take?

Answer 2

30-90 minutes

Question 3

advantages of oral administration?

Answer 3

cheap

easy

Question 4

when a drug is taken orally, where does it then go?

Answer 4

to the gut (GI system) and then to the liver

Question 5

how long does IV admin take?

Answer 5

2-3 minutes

Question 6

what is the bioavailability of oral?

Answer 6

10-50%

Question 7

what is the bioavailability of IV?

Answer 7

100%

Question 8

how long does intramuscular and subcutaneous take?

Answer 8

10-20 minutes

Question 9

how do you administer a drug subcutaneously?

Answer 9

into fat deposition

Question 10

how do you administer a drug intramuscularly?

Answer 10

into the muscle

quad or deltoid administration

Question 11

when would you use IM or subcutaneous?

Answer 11

when you want a slower release of the drug but to bypass 1st metabolism of the liver

Question 12

how long does rectal administration take?

Answer 12

5-10 minutes

Question 13

how is the drug metabolised rectally?

Answer 13

by the liver via the anterior mesenteric artery

Question 14

how does inhalation of the drug work?

Answer 14

goes to the lungs then the bloodstream

Question 15

how does transdermal work?

Answer 15

patches applied to the skin then enters the bloodstream

Question 16

how does topical work?

Answer 16

applied directly to the skin so it has a local action

Question 17

how are transdermal and topical different?

Answer 17

transdermal - into bloodstream

topical - local effect

Question 18

what is sublingual?

Answer 18

under the tongue

Question 19

why is sublingual administration so fast?

Answer 19

underneath the tongue has such a rich blood supply and it bypasses the liver

Question 20

how does intranasal work?

Answer 20

into the nose

local or into blood stream

Question 21

how does intrathecal work

Answer 21

into the cerebrospinal fluid into the ventricular system or into the bloodstream

Question 22

what is an advantage of intrathecal administration?

Answer 22

bypasses the BBB to allow drugs to work on the brain

Question 23

what is epidural administration?

Answer 23

outside of the spinal dura

Question 24

when is epidural administration used?

Answer 24

local anaesthetic for peripheral nerve and spinal nerve

Question 25

where does intraarticular administration go?

Answer 25

into the joint space

Question 26

what is the fastest route of administration?

Answer 26

IV

Question 27

what are the slowest routes of administration

Answer 27

IM and oral

Question 28

how do drugs go from the GI tract to the liver?

Answer 28

portal vein

Question 29

where does first pass metabolism occur?

Answer 29

gut and liver

Question 30

what is first pass metabolism?

Answer 30

when the concentration of the drug is greatly reduced before it reaches the systemic circulation

Question 31

what is a pro-drug?

Answer 31

a biological inactive parent drug that requires a chemical or enzymatic transformation to release active drug

Question 32

Where are pro-drugs converted into the active form?

Answer 32

The liver

Question 33

how are pro-drugs converted into the active form?

Answer 33

liver enzymes cleaves off the carrier molecule, activating the drug rather than the drug just being digested

Question 34

what is the purpose of pro-drugs?

Answer 34

protecting the drug from first pass metabolism in the liver

Question 35

give an example of a pro-drug and how it works

Answer 35

L-dopa - used to treat Parkinsons | As a protected molecule it can cross the BBB

Question 36

advantage of using L-dopa as a prodrug?

Answer 36

smaller dose given which is safer

Question 37

explain how pro-drugs are used in cancer medication?

Answer 37

tumour specific gene delivery enzyme expression so that prodrug can bind toxic drug is given as a prodrug and only targets cancer cells which have the enzyme cytotoxic drug kills the tumour cell cell dies and drug goes to neighbouring drugs - bystander effect

Question 38

what are the two categories of reactions that happen in the liver?

Answer 38

phase 1 and 2

Question 39

what happens in phase 1 liver reactions?

Answer 39

biotransformation to make drug more water soluble so it can be excreted.

Question 40

name examples of reactions that happen in phase 1 reactions?

Answer 40

oxidation hydrolysis reduction

Question 41

what happens in phase 2 reactions?

Answer 41

synthesis reactions to become more water soluble

Question 42

name examples of reactions that happen in phase 2 reactions?

Answer 42

conjugation with glycine, sulfate, glucuronic acid

Question 43

name the methods of eliminating a drug?

Answer 43

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Question 44

what is the main metabolic organ?

Answer 44

the liver

Question 45

what things can happen to a metabolite that leaves the bile via the liver?

Answer 45

excreted in the kidneys | reabsorbed and go back to the liver

Question 46

what is clearance?

Answer 46

rate of elimination in relation to drug concentration in the plasma

Question 47

how is clearance calculated?

Answer 47

rate of elimination divided by concentration remaining

Question 48

define half life of a drug

Answer 48

time taken for plasma concentration to reduce to half its original concentration

Question 49

how is half life calculated?

Answer 49

volume of distribution divided by clearance x0.7

Question 50

define zero order elimination

Answer 50

the elimination of a constant quantity of a drug per unit time

Question 51

define first order elimination

Answer 51

the elimination of a constant fraction per unit time

Question 52

which order of elimination do most drugs use?

Answer 52

first

Question 53

how many half lives does it take for a drug to be removed from the body?

Answer 53

5

Question 54

what is the therapeutic window?

Answer 54

where a drug has therapeutic effects

Question 55

what is the lag period?

Answer 55

the time before therapeutic effect - time for absorption to happen and drug to get into circulation

Question 56

what is the safe range of a drug?

Answer 56

between the minimum therapeutic concentration and the minimum toxic concentration

Question 57

before how many half lives will accumulation occur?

Answer 57

4

Question 58

what is a loading dose?

Answer 58

a larger dose given to get into the therapeutic range quicker

Question 59

what is a maintenance dose?

Answer 59

maintains the drug in the therapeutic window

Question 60

what factors effect drug metabolism?

Answer 60

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