medicines in psychiatry Flashcards
examples of use of (chemical/ actual) drugs- meds in psychiatry
drugs for depression, psychosis
example of electrical stimlation use in psychiatry
ECT electroconvulsive therapy for depression, neurostimulation for pain syndromes (parkinsons)
is there any case of structural rearrangement use in psychotherapy ?(surgery/ orthopaedics)
psychosurgery= deep brain stimlation for severe depression
ex. of talking psychotherapies
CBT, exposure for phobias- exposure of someone with a phobia to this phobia
what is the structure of gaba a and gaba b receptors?
differ in STRUCTURE
gaba-a: ligand gated ion channel
gaba -b: classic g- protein linked receptor
same function: both receptors for gaba which is inhibitory neurotransmitter
what different drugs act on gaba a vs gaba b?
gaba a: alchohol, benzodiazepines, and
gaba b: GHB (GAMMA HYDROHYBUTYRATE) and balcofen
What is a PAM and where do pams bind on gaba receptors?
positive allosteric modulator, means that on gaba receptors they wont bind where gaba binds, theyll bind on allosteric site and enhance the effects of the natural transmitter
examaple of GABA -A PAM
alprazolam (sleep promoting, muscle relaxing, muscle convulsant, anxiolytic)
where on receptors do agonists bind? for ex where on gaba rec.)
on the site of the natural agonist so where gaba would bind
example of gaba b agonist
baclofen- acts on site of gaba (decreases alchohol craving in alchohol dependant patients)
does balcofen have any indications in psych or other system?
this is more to appreciate the NbN (neuroscience based nomenclature) and that it basically presents indications across all systems if they are present ex bacofen indication of spasticity: neurological
what are the 4 targets of psych drugs
enzymes,
ion channels
neurotransmitter reuptake SITES
receptors
what is an issue with lenzyme target drugs?
theres lots of enzymes in liver and these drugs may also have effects on liver
what part of the neuron do most psych drugs work in?
synapse
what are autoreceptors?
receptors on pre synaptic neuron where neurotransmitters bind and limmit the release of further neurotransmitter
what happens to neurotransmitter in the synapse? how is it removed?
most of it reuptaken some of it broken down by enzymes in synapse
what is the breakdown enzyme inhibited for depression and anxiety and what neurotransmitters does it breakdown?
monoamine oxidase
MAOIs (inhibitors)
enzyme breaks down stuff like dopamine, serotonin, noradrenaline
what is the only proven therapy for dementia?
acetylcholinesterase inhibitors,
inhibit enzyme acetylcholinesterase which breaks down acetylcholine (substance needed to stay awake and remember things )
what is an enzyme inhibitor used for mood stability
lithium blocks glycogen synthase kinase (neurotransmitter that maintains neuronal functional stability)
which of the four drug target types are the most common?
receptro targeting medicines and specifically receptor antagonists
what receptor blocker is used for schizophrenia
dopamine receptor blocker
what receptor antagonist for depression
serotonin receptor type antagonist
what receptors are targeted in drugs for sleep
histamine receptor antagonists
or
benzodiazepines = GABA agonist
receptor agonist for ADHD example
guanfacine - noradrenaline agonist
explain a little bit difference between the meaning of agonists and antagonists vs inhibitory and exitatory neurotransmitters
Thing to consider: agonist antagonist vs inhibitory excitatory neurotransmitter - all aneurotransmitter are agonists: they stimulate aRECEPTOR, inhibitory means they inhibit CELL depolarization
reuptake site targetting meds for depression and anxiety or only depression
citalopram: enhances serotonin = serotonin reuptake nihibitor
desipramine: noradrenaline reuptake inhibitor enhances noradrenaline (only dp)
reuptake inhibitor for adhd
methylphenidate: dopamine reuptake inhibitor (DRI) - enhances dopamine
what is a drug that still increases the action of a neurotransmitter by increasing its conc in synapse but not by decr its reuptake by incr its release adn what is it used for?
adhd amfetamine
what is 5HT
serotonin
where do 5-HT neurons originate and then synapse
they originate in brainstem
they synapse in cortex, hypocampus or wherever…
what structure is the target of SSRIs and what does SSRI stand for
selective serotonin reuptake inhibitor
target is serotonin transporter
how many genes control serotonin post synaptic receptors and what does this mean for their variety
12 genes
very variable
are most post synaptic serotonin receptors inhibitory or excitatory
most are excitatory
is 5-HT 1A and 5-HT 2A inhibitory or excitatory
1A inhibitory and 2A excitatory
what is basically the function of ion channel blockers?
block neuronal excitability
what are 2 examples of sodium channel blockers
sodium valporate and carbamazepine both used for epilepsy and mood stabilisation
what is an example of calcium channel blockers and use
gabapeptin and pregabalin used for epilepsy and anxiety (but even sleep and pain)
what are the two major types of neurotransmitters and which are the main / most important in brain
fast acting - are the on off switch : memory movement vision
and
slow acting 5% of all neurons - add “colour, meaning” to brain functions:
emotions, drives, valence of memory
which are the fast acting neurotransmitters and their proportions in brain
excitatory: glutamate : 80%
inhibitory : gaba: 15%
what kind of neurons use glumamergic neurotransmission?
pyramidal cells
what kind of neurons use gabaergic neurotransmission?
interneurons
which are the slow acting neurotransmitters?
dopamine, serotonin, noradrenaline, acetylcholine
also endorphins and other peptides
in what conditions do you see glutamate excess and what drugs treat it
alchoholism and epilepsy
treat with blockers
acamprosate and kematine
and
perampanel
condition associated with decr in gaba and drug
anxiety- gaba enhancer- benzodiazepines
disorders with decr in 5-ht and drugs
depression and anxiety - SRIs and MAOIs - serotonin enhancers
disorders with excess dopamine
psychosis,
dopamine receptor blockers
excess noradrenaline impact and drug
nightmares - prazosin - blocker
acetylcholine deficiency disorder adn drug
impaired memory/ dementia, acetylcholine esterase enzyme blockers
what system do most depression targeting drugs act on?
5HT systems (meaning, somehting serotonin related) - some do so exclusively and others include serotonin target along with other targets
what is an examample of a drug with 2 neurotransmitter target systems
SNRIs serotonin noradrenaline reuptake inhibitors
2 depression drugs that dont target 5-HT SYSTEM
NRI noradrenaline reuptake inhib
DRI dopamine reuptake inhib
is melatonin agonist 5HT system related or not?
IT IS
name 2 multimodal drugs (not drug types, DRUGS)
Vilazodone - USA- SSRI- 5-HT 1A agonist
vortioxetine -SSRI and multiple other 5- 5ht receptor effects
what is the partial agonist version of heroin (ex of medicine opiod: methadone) ?
buprenophine
partial agonist version of haloperidol
aripiprazole
partial agonist version of nictoine and its use
varenicline (use for smokinf cessation)
what is the difference(S) between partial agonists and full agonists
1) partial agonists have a lower maximum efficacy than full agonists
2) in states of really high nt concentration parital agonists can work as antagonists
knowing the properties of partial agonists what is an advantage?
imporved safety especially in preventing overdose
what are inverse agonists? what do they do compared to agonist and antagonist?
inverse agonists bind on receptors have the opposite effect to what the agonist would have had.
think of agonist: an effect
antagonist: blocks agonist form binding
reverse agonist: binds and stimulates receptor into a different action to that of agonist
examples of inverse agonists
GABA a5IA : one of the action of a drug: allosteric smth gaba
is pro cognitive and used for dementias
: on some receptors has a positive effect (acts as gaba agonist) - increases attentiona nd memory
on other gaba receptors it actually has negative effects so it reverses gaba action (reverse agonist)- sobers you up bc it reverses the stimulating effect of alchohol on gaba
how many proteins make up a gaba receptor and what does this mean for variety
5 dif proteins, there is hige variety Think about fact that even though some subtyoe receptors seem to be very small on pie chart, even they are stll more than dopamine receptors in brain
what is the main site and the other sites of e receptor called? (one where natural agonist binds?)
orthosteric site and allosteric sites
what is the action that leads to neuron inhibition uppon gaba binding to a receptor?
cl- conductance leading to neuron inhibition
what type of receptor is gaba a and gaba ab
gaba a is ion channel linked gaba b is g protin linked
what site do gaba benzodiazepines, alchohol, neurosteroids bind?
gaba: beta: orthosteric
allosteric:
benzo on gamma subunit
ethanol (alc) alpha subunit
what type of drugs are haloperidol and clozapine and what are they used for?
dopamine receptor blockers for schitzophrenia
compare haloperidol and clozapine
haloperidol is very selective, binds only on d2 receptor and only on eextra: alpha 1 receptor
vs
clozapine binds on so many receptors so has side effects such as weight gain, sedation, metabolic syndrome
what are amitriptyline and citalopram used for? what type are they
56-HT reuptake blockers
amitriptyline and citalopram
amitriptiline is tricyclic so has many binding sites both receptors and transporters so has many side effects especially from histamine and acetylcholine receptor blockage
citalopram is SELECTIVE serotonin reuptake inhibitor, means its selective ONLY FOR THAT, does not bind to NAYTHING else so has no side effects linked to other bindings, only related to too increased serotonin
