Pharmacodynamic Principles Flashcards
what type of drug posses affinity and intrinsic efficacy
agonist
what class of agonist binds to the same site as endogenous ligands
primary agonist
what class of agonist binds to a different region of the receptor
allosteric agonist
what is an example of an allosteric agonist
anaesthetic drug effects on GABA receptors
what type of agonist produces maximal efficacy
full agonist
what type of agonist can bind to and activate the receptor but produces a sub-maximal effect
partial agonist
what opioid receptor acts a full agonist
morphine
what opioid receptor is a partial agonist
buprenorphine
what type of drug possess affinity but lacks intrinsic efficacy
antagonist
what is the function of antagonistic drugs
prevent the action of natural agonists (neurotransmitters & hormones)
what is an example of a drug that can act as an agonist and antagonist
butorphanol
how does butorphanol act on mu receptors
antagonist
how does butorphanol act on kappa receptors
agonist
how does butorphanol act on kappa receptors
agonist
what are the two types of antagonism
competitive & non-competitive
what type of antagonism is present when the antagonistic drug acts on the SAME RECEPTOR as the agonist
competitive antagonism
what type of antagonism is reversible when it can be over come by the agonist concentration
competitive antagonism
what are examples of competitive antagonistic drugs
atropine
propranolol
how will a competitive antagonist impact the potency of a drug
lowers potency
how does competitive antagonism effect efficacy
efficacy remains constant
which antagonism type is irreversible
non-competitive
what type of bond is used by antagonistic non-competitive drugs?
covalent
how does the use of a non-competitive antagonistic drug effect potency
decreases potency
how does the use of a non-competitive antagonistic drug affect efficacy
decreases efficacy
True or False:
A non-competitive EMax will eventually equal that of the regular drug
FALSE
there will always be a decrease in efficacy
Besides comparing the efficacy of a drug with different amounts of antagonists, what else can those graphs be used for
determine antagonist strength
what type of site does the non-competitive drug bind to
allosteric site because it causes change to the active site
what type of agonist acts at the same receptors as an agonist but produces an opposite pharmacological effect
inverse agonist
what are examples of inverse agonists
H1 receptor antihistaminergic drugs
B-blockers / carvedilol
antipsychotic drugs
antihypertensive drugs
which type of agonist would you expect to see to bind to only active receptors
full agonist
competitive antagonist
what agonist type would you expect to see occupying mostly active state receptors but some resting state
partial agonist
what is the result of the partial agonist only occupying most but not all of the active state receptors
lowered max response / partial response
what drug type do you expect to see occupying an equal amount of active and resting state receptors
antagonist
what agonist type would you expect to see only occupying resting state receptors
inverse agonist
competitive antagonist
what is the effect of an inverse agonist only occupying resting state receptors
produces the opposite effect of the agonist
True or False:
Drug response is a linear function of drug occupancy
true
what occurs when a drug occupies all available receptors
maximal response
when is a response from a drug terminated
when it dissociated from the receptor
what is occupancy theory of a drug
maximal response is proportional the the drug-receptor complex bindings
when does max response of a drug occur
when all receptors are occupied at equilibrium
when there is no ligand present, how is the equilibrium balanced
lies far to the left
what state of receptor do agonists have a higher affinity for
active state
which dose-response relationship describes a drug effect that increases in proportion to an increasing drug dose
graded dose-response
which dose-response is used to measure the effect of a drug on an individual person
graded dose-response
what can a graded dose-response be used to determine
efficacy of a drug over time
which dose-response relationship is used to describe a drug effect as present or absent
quantal dose-response
which dose-response relationship should be determined with a population of people
quantal dose-response
what does a quantal dose-response graph plot
rate of an outcome occurrence in a population against a drug dose
besides drug effects on a population, what else can a quantal dose-response graph determine
toxic levels of a drug
which dose-response relationship results in a greater magnitude of response as the dose increases
graded dose-response
True or False:
Using Quantal dose-response, a higher percentage of the population will be affected as the dose is increased
true
when is a drug considered unsafe/toxic in terms of standard safety margin
drug has a low safety margin
what is used to determine the standard safety margin
ED (effective dose)
LD (lethal dose)
what is used to evaluate the safety of a certain drug
therapeutic index
what kind of receptor regulation is present when there is a loss of receptors present
downregulation
what kind of regulation is present when there is an increase of receptors present
upregulation
what is the outcome of upregulation
more sensitive to a hormone or neurotransmitter
how is upregulation created
long term administration of an antagonist
explain the process of using prolonged antagonistic drugs on upregulation
all represent receptors become blocked forcing the cells to create new receptors for ligands to bind to
what causes downregulation
long term exposure to agonists
what is the result of downregulation
decreased responsiveness
