pharmacology

Question 1

define pharmacodynamics

Answer 1

what a drug does to the body

Question 2

define pharmacokinetics

Answer 2

what the body does to a drug e.g. absorption, metabolism

Question 3

define efficacy

Answer 3

the ability of an agonist to evoke a cellular response

Question 4

define oral availability

Answer 4

the fraction of the drug the reaches the systemic circulation after oral ingestion

Question 5

define systemic availability

Answer 5

the fraction of the drug that reaches the systemic circulation after absorption

Question 6

what is the systemic availability of drugs administered IV

Answer 6

100%

Question 7

what can IV administration result in

Answer 7

high levels of drug at heart

Question 8

what route of drug administration is frequently used for nocturnal

Answer 8

rectal

also when oral route compromised e.g. nausea and vomiting or unconscious

Question 9

what is infrequently used in the UK

Answer 9

rectal

Question 10

which route totally avoid first pass metabolism

Answer 10

IV, buccal and sublingual

Question 11

what is the route for drugs that cause local tissue damamge

Answer 11

IV

Question 12

what route allows rapid onset of lipid soluble drugs

Answer 12

IM

Question 13

what route is good for volatile compounds

Answer 13

inhalation

Question 14

what route is ideal for local effect

Answer 14

topical

Question 15

what route can produce a smooth plasma concentration

Answer 15

transdermal

Question 16

what drugs can move freely by diffusion

Answer 16

ionised drugs of low molecular weight that are not bound to protein

Question 17

where does the absorption of oral drugs mainly occur

Answer 17

small intestine

Question 18

what is the volume of distribution of a drug

Answer 18

the apparent volume in which it is dissolved

Question 19

describe first order kinetics

Answer 19

rate of eliminations is directly proportional to drug concentration

Question 20

define clearance

Answer 20

the volume of plasma created of drug in unit time

Question 21

what does clearance only apply to

Answer 21

1st order kinetics

Question 22

what does clearance determine

Answer 22

the maintenance dose rate

Question 23

define steady state

Answer 23

rate of drug administration = rate of drug elimination

Question 24

how many half lives does it take to reach steady state in 1st order kinetic drugs

Answer 24

5 half lives

Question 25

define loading dose

Answer 25

initial higher dose of a drug given at the beginning of a course of treatment before stepping down to a lower maintenance dose

Question 26

reason for LD

Answer 26

dec time to steady sate for drugs with long half lives

Question 27

define zero order kinetics

Answer 27

drug initially eliminated at a constant rate, and then converted to 1st order at lower conc

Question 28

zero order also called

Answer 28

saturation kinetics

Question 29

what drugs exhibit 0 order kinetics

Answer 29

ethanol and phenytoin

Question 30

define xenobiotic

Answer 30

substance that is foreign to the body

Question 31

what drug is converte from inactive prodrug to active compounds

Answer 31

enalapril to enalaprilat

Question 32

what drug gains activity

Answer 32

codeine to morphine

Question 33

what drugs has unchanged activity

Answer 33

diazepam to nordiazepam

Question 34

what does phase 1 in the liver do

Answer 34

make rug more polar | e.g. oxidation reduction, hydrolysis

Question 35

what does phase 2 in the liver do

Answer 35

conjugation e.g. methyl group

Question 36

what type proteins are cytochrome p450

Answer 36

haem proteins

Question 37

what reactions do p450 mediate

Answer 37

oxidation

Question 38

describe the monooxygenase p450 cycle

Answer 38

drug enters the cycle and leaves as hydroxy product

Question 39

define glucoronidation

Answer 39

transfer glucoronic acid to electron rich atoms of the substrate

Question 40

define hyperpolatisation

Answer 40

the membrane potential becomes more negative

Question 41

why does Na move inward

Answer 41

conc and electrical gradient is inward

Question 42

why does K move outward

Answer 42

conc gradient > electrical gradient

Question 43

define absolue refractory period

Answer 43

no stimulus can elicit a second action potential

Question 44

define relative refractory period

Answer 44

stronger than normal stimulus can elicit a second AP

Question 45

define saltatory conduction

Answer 45

in myelinated axons AP jumps from one node of Ranvier to the next

Question 46

what effect does Guillan Barree have on nerve conduction

Answer 46

slows it

Question 47

where in the AP does the absolute RP occur

Answer 47

downstroke

Question 48

where in the AP does the relative RP occur

Answer 48

undershoot

Question 49

how do impulses spread in non myelinated axons

Answer 49

passively

Question 50

postganglionic neurotransmitter in sympathetic division

Answer 50

noradrenaline

Question 51

sympathetic outflow

Answer 51

T1-L2 | thoracolumbar

Question 52

why is the sympathetic innervation of the adrenal gland special

Answer 52

pre-ganglionic (mediated by ACh)

Question 53

parasympathetic outflow

Answer 53

CN III, VII, IX and X and sacral spina nerves | cranioscarl outflow

Question 54

how many subunits do nicotinic ACh receptors consist of

Answer 54

5

Question 55

para - M1 pathway

Answer 55

Gq - stimulates PLC - inc acid secretion

Question 56

para - M2 pathway

Answer 56

Gi - inhibit AC and open K channels - dec HR

Question 57

para - M3 pathway

Answer 57

Gq - stimulate PLC - inc salivary gland secretion and contraction

Question 58

amphetamine action

Answer 58

causes the release of transmitter from sympathetic post-ganglionic neurones in a manner that doesn’t require the opening of presynaptically located voltage activated Ca channels