Brain and Behaviour Flashcards
What is the corpus striatum made up of?
Caudate nucleus and putamen
What do the putamen and globus palidus make up?
Lentiform nucleus
What type of neurons are medium spiny neurons?
Inhibitory GABAergic neurons
What do D1 receptors do?
They increase CAMP, leading to increased phosphorylation and increased sensitivity of striatum to glutamate
In PD what part of the brain loses dopaminergic neurons?
Substantia Nigra pars compacta
What medication primarily treats dyskinesia symptoms?
Amantadine
What is abnormally repeated in Huntington’s?
CAG codon - glutamate
What chromosome do you find mutated Huntington gene?
Chromosome 4
What is lost in Huntington’s?
Loss of GABAergic neurons in striatum = less inhibition = shift towards direct pathway
Where can you find the aggregated Huntintin?
They are intranuclear inclusions
What mutations are associated with PD?
SNCA mutation, codes for alpha synuclien
LRRK2
GBA, codes for B glucocerebrosidase
What enzyme converts L-tyrosine to L-dopa?
Tyrosine hydroxylase
What enzyme converts L-dopa into dopamine
L-aromatic amino acid decarboxylase
What are ropinirole, rotigotine, apomorphine, bromocriptine examples of?
Dopamine agonists
What are rasagiline, selegilline and safinamide examples of?
MAO-b inhibitors
How do anticholinergic compounds work for PD?
Counteract imbalance - dopamine loss leads to hyperactivity of cholinergic cells
What is tetrabenazine?
A vesicular amine transporter inhibitor - causes depletion of neuroactive peptides such as dopamine in nerve terminal (for HD)
Name some antidopaminergic drugs
haloperidol, olanzapine
What do lesions of premotor cortex lead to?
Motor apraxia - difficulty performing complex tasks (but normal reflexes)
What might abnormal saccades be a sign of?
Damage to frontal eye fields
Where does decussation happen in corticospinal tract? And if there is injury below decussation what will you get?
C1-C5
Motor deficit on the same side
Where does rubrospinal tract arise? and what does it do?
Red nucleus in brain stem - it excites flexor muscles and inhibits extensor muscles
What does tectospinal tract do and where does it arise?
It originates in the superior colliculus and it coordinates voluntary head and eye movements
Which posturing indicates lesion above red nuclues?
Decorticate
If the cerebellum is injured on one side where will symptoms be and why?
On the same side as lesion as anterior spinocereballar tract decussates twice and posterior is direct = net effect zero
What is anterior lobe syndrome?
Damage to spinocerebellum - leads to ataxic gait, hypotonia, depressed or pendular reflexes. Can also be seen in alcoholics due to malnutrition
What are symptoms of flocculonodular syndrome? (vestibulocerebellar injury)
Little control of axial muscles, ataxic gait, tendency to fall to side of lesion, nystagmus
Often occurs due to medulloblastoma tumour in 4th ventricle that compresses nodulus
Name the capsaicin/vanilloid receptor
TRPV1 channel
What does ASIC channel stand for?
Acid sensing ion channel
What nociceptor detects menthol?
TRPM8
What can cause congenital insensitivity to pain?
Loss of Nav1.7
What causes inherited erythomelalgia?
Mutation of SCN9A gene that encodes Na1.7
How do C fibres activate lamina 1?
Via excitatory interneurons in lamina II
What causes congenital insensitivity to pain anhidrosis?
mutation to TRKA gene
What region modulates descending pain?
PAG. (Which can then activate locus coreulus which contains noradrenergic neurons - further modulation)
How can serotonin modulate pain?
serotonin and noradrenlin active interneurons which can stimulate release endogenous opioids which open Cl- channels and block Ca2+ channels on sensory neurons inhibiting firing
AND
serotonin can activate 5HT1a receptors on first order neurones to inhibit neurotransmission
How do you treat morphine overdose?
NA-loxone (opiate antagonist)
How does paracetamol work?
It stops prostaglandin synthesis by reducing active form of COX1 and COX2. It also inhibits reuptake of endogenous cannabinoids
What is celecoxib an example of and why is it not normally used?
A selective COX2 inhibitor and bc of the cardiovascular effects
How does diclofenac work?
It inhibits prostaglandin formation but it preferentially inhibits COX2
What do carbamazepine and sodium valproate act on?
Sodium channels - prevent sustained firing of action potentials
What does pregablin work on?
Inhibits Alpha2 delta1 subunit of calcium channels. Causes decreased release of neurotransmitters
What type of drug is baclofen?
muscle relaxant - GABAb receptor agonist
How does tramadol work?
Acts on mu receptors and interacts with monoaminergic systems - inhibits 5ht and NA uptake
What drug is duloexetine?
SNRI
Clonazepam is used for trigeminal neuralgia, what kind of drug is it?
a benzodiazepine - amplifies GABAa receptor
What is the MAO of local anaesthetics?
Blockade of sodium channels
What is the name of fluid found in ear which is rich in potassium?
Endolymph
What is Meniere’s disease?
disorder of inner ear - vertigo, tinnitus etc. results from excessive endolymph accumulation
What is Hallpike maneouvre?
Lower head to the floor, if patient gets dizzy the ear pointing the floor is affected
What is the pathopysiology of cell death in ischaemic stroke?
Less ATP- failure of Na/K pumps, resulting in depolarisation. Leads to influx of calcium ions and glutamate release. Elevated calcium = cell death
What kind of stroke is likely to be pure motor OR pure sensory Or cause ataxic hemiparesis
lacunar stroke
What is alteplase
Dissolves clot in a stroke by cleaving plasminogen
What is secondary prevention of stroke?
clopidogrel 75mg daily or aspirin and a statin such as atorvastatin
Which region of brain do you find prominent loss of cells in epilepsy?
CA2 and CA3 hippocampal area
What cells are lost in epilepsy?
Inhibitory chandelier cells
What cells can cause abnormal neuronal excitability in epilepsy?
Glial cell deficiency
What epilepsy drugs induce drug metabolism in the liver and are also not used in absence seizures?
phenytoin and carbamazepine
What epilepsy drug is zero order?
Phenytoin
What is an anti-epileptic drug that can be used in all types of seizures?
Sodium valproate
What GABA receptor does Topiramate act on?
Gaba A topirAmate
What epilepsy drugs target calcium channels?
Ethosuximide and Gabapentin
What are the difference between benzodiazepines (clonazepam) and barbiturates (phenobarbitone, striripentol)?
Both work on GABAa but Ben increases channel opening frequency and Barb makes them open for longer.
Ben wants it more frequently, Barb wants it for longer
What do you give in status elipticus?
Lorazepam or diazepam
Difference between primary headaches and secondary headaches?
Primary - absence of physical signs eg migraine,
Secondary - presence of signs eg meningitis, sinusitis
What centre is activated in migraine?
Trigeminal vascular system
What neurotransmitter acts on blood vessels in dura causing them to dilate in migraine?
Serotonin
What area leads to central sensitisation which mediates allodynia in mirgaine?
Spinal trigeminal nucelus caudilis
What part of the brain is responsible for the premonitory changes in migraine?
Hypothalamus
What is an important inflammatory neuropeptide that gets released in migraine?
CGRP
What metabolite increases in urine immediately after a migraine?
5HIAA metabolites
What is the mechanim of action of triptans?
5HT 1D/1B agonists - vasoconstrictive
What type of drugs are rimegepant, ubrogepant, atogenpant and how do they work?
Gepants - small molecule CGRP antagonists. They prevent vasodilation
What functional deficits are normally present in a middle cerebral artery stroke on the non dominant hemisphere?
Neglect syndrome - left becomes more active so results in attention and and eye movements towards the right. Might bump into things on left
Functional deficits of anterior cerebral strokes?
contralateral sensorimotor loss below waist. Personality defects if frontal lobe
Functional deficits of posterior cerebral strokes?
Contralateral homonymous hemianopia, reading writing deficits
What cranial nerve is normally affected by epidural hematoma?
CN III. Because of increase in pressure - herniation of temporal lobe (uncal herniation), gets compressed at tentorial edge (eyelid drooping, pupil dilation)
What type of extra-axial bleed is a venous bleed?
Subdural haematoma
What type of bleed often presents with a severe thunderclap headache?
Subarachnoid
What might an Alzeimher’s post mortem look like?
1) Extreme shrinkage of hippocampus,
2) extreme shrinkage of cerebral cortex
3) severely enlarged ventricle
What are the senile plaques in AZD made up of?
deposits of amyloid-beta protein
What are neurofibrillary tangles in AZD made up of?
tau protein
What might you see in a FGD-PET scan for AZD?
Hypometabolism in temporal, parietal, frontal regions and posterior cingulate cortex
What cleaves amyloid precursor protein in AZD?
beta secretase and gamma secretase to produce A-beta peptides
in healthy brain it is alpha secretase and gamma secretase to P3 peptide
What does hyperphosporylation of Tau cause?
Causes it to detach from microtubules which makes them become unstable and depolymerise
Which APOE mutations cause what?
APOE epsilon 2 is rare and can protect, epsilon 3 is neutral and epsilon 4 increases risk of AD
What mutations can lead to early onset AZD?
Presenlin-1 (chromosome 14)
Presenlin-2 (chromosome 1)
Amyloid precursor protein (chromosome 21)
Name some acetylocholinesterase inhibitors
Donepezil, Galantamine and Rivastigmine
Don Galanting to the River.
Name a NDMA receptor antagonist for AZD
Memantine (think people doing MDMA making memes)
What is the Default Mode network and how does it function in patients with depression?
It is a network of brain regions active when brain is at wakeful rest. Depressed patients have increased functional connectivity between DMN and fronto-parietal networks
What areas of brain are hyperactive in ruminating thoughts?
Hippocampus, amygdala, subgenual cinugulate medial prefrontal cortex
What areas of the brain are hypoactive in ruminating thoughts?
ventrolateral prefrontal cortex, dorsolateral prefrontal cortex
How does ketamine work as an antidepressant?
An NMDA glutamate receptor antagonist, enhances transmission at glutamergic synapse
What is brexanalone?
Used in post partum depression. Progesterone related compound - post modulator of GABAa
What can monoamine oxidase inhibitors interact with?
tyramine containing food
Name some selective serotonin reuptake inhibitors
Citalopram, fluoxetine, paroxetine
What type of drug is moclobemide?
Monoamine oxidase inhibitor (selective for MAOa)
Social anxiety and depressive illness
What class of drug is Duloxetine?
SNRi
What kind of drug is Agomelatine?
It is a a new drug for depression. It is an agonist at MT1 and MT2 receptors
How is bipolar managed?
With lithium
What part of the brain evaluates the degree of pleasure or pain in an outcome and then suggests appropriate action?
Anterior cingulate cortex
What is the role of the insula in memory?
Makes the decision whether an event is worth remembering or not. Insula = internalise feelings or not?
What are the low and high road through which fear reaches the amygdala?
Low - fast - fight or flight. Thalamus»_space;> amydala
High - slow. Thalamus»_space; sensory cortex»_space; amygdala.
What is Urbach Weithe disease?
Rare disease that causes collagen to build up in amydala - no fear
What parasite can exploit the amygdala and leads to increased risky behaviour?
Toxoplasma gondii
What are panda eyes / orbital ecchymoisis signs of?
Basal skull fracture
In severe TBI what seizure prophylaxis would you use?
Phenytoin / levetiracetam
What parts of the hypothalamus promotes arousal and sleep?
Arousal - tuberomammillary nucleus TMN and suprachiasmatic nucleus
Sleep - ventrolateral preoptic nucleus
How can consciousness be assessed through auditory stimulation?
positive P300 around 300ms after auditory change
MMN (mismatch negativity) around 100-250ms after an auditory change
What is often damaged in locked in syndrome?
Ventral pons - interruption of corticospinal and corticobulbar tracts
Zolpidem can be used for brain injury. How does it work?
It is indirect GABAa receptor agonist. Restores normal inhibition in the GPi, allows an increase of thalamic excitatory influence on prefrontal cortex to initiate movement
What an be up-regulated in drug abuse?
dynorphin receptors
In cocaine abuse what receptors are there less of?
D2 receptors
What is upregulated in all kinds of addiction?
Delta- Fos-B
What inhibits aldehyde hydrogenase in addiction?
Disulfiram
What antidepressant drug can be given for nicotine addiction?
Bupropion (a monoamine reuptake inhibitor)
What opioid agonists can be used for opiate addiction?
Methadone - opioid agonist. Buprenorphine - partial agonist
What does naltrexone do?
It is an opioid antagonist. Blocks high that addicts might have, used after detoxification
What do clonidine and lofexidine do for addiction?
They are alpha-2-adrenoreceptor agonists - they alleviate the autonomic hyperactivity during withdrawal
What will a schizophrenia MRI show?
Larger ventricles, and a reduction in brain volume
What part of the brain is hyperactive in SCH?
Mesolimbic dopaminergic pathway (think hyper-limbs. someone thrashes their limbs around)
What area is hypoactive in SCH?
mesocortical dopaminergic pathway and nigrostriatal pathway
What pathway can be blocked in SCH and can lead to a rise in prolactin and sexual dysfunction?
Blockade of tuberoinfundibular pathway
How can you test for frontal cortical dysfunction testing?
Wisconsin card sorting
What do all SCH drugs do?
Antagonists at D2 receptors
What are first line for SCH treatment
atypical antipsychotics - risperidone, olanzapine, clozapine, aripiprole etc
(dopamine D2 receptor antagonists, and also signific antagonistic activity at 5HT2a receptors
What antipsychotic can cause neutropenia or agranulocytosis?
Clozapine
How does pregablin treat insomnia?
It binds to alpha 2 delta 2 subunit of voltage gated calcium channels
What are orexins?
They are peptides produced in the hypothalamus as either orexin A or orexin B. They regulate arousal, appetite and wakefulness
How does suvorexant work?
It is a orexin antagonist to treat insomnia
What do the Z drugs bind to?
alpha 1 subunit of GABAa
Name some benzodiazepines?
Clonazepam, alprozolam, lorazepam
What kind of drugs are used for stage fright like symptoms?
B adrenoreceptor antagonists (propanolol)
How do benzodiazepines work?
They are positive allosteric modulators - they enhance GABAa receptor activity. Means increased chloride influx which means firing less likely
How is benzo overdose managed?
Flumazenil - antagonist at BZD sites
What receptors are redistributed to potentiate or weaken memories
AMPA receptors
What can be examined in lumbar puncture of patient with MS?
oligoclonal bands of IgG. OCB bands determine presence of neurofilaments
What do MS drugs do?
They all suppress the immune system. Alemtuzumab and cladribine are first line for induction and they work on CD52. For acute relapse = high dose corticosteroid
Romberg’s test what does it mean if problem when eyes are open and closed vs just closed?
open and closed = cerebellar deficit
closed = propioceptive deficit
What is the Uthoff phenomenon?
It is temp vision loss linked to physical activity (due to temp) that is associated with optic neuritis
What type of EEG will you get when awake?
Low amplitude waves as the asynchronous firing cancels out
What free radical scavenger is released during sleep?
Melatonin from pineal gland - removes free radicals - antioxidant
What part of brain decides when we need sleep?
Hypothaolamus decides and then it commands to pons to turn off reticular formation and trigger sleep
What hormones inhibits and increases sleep?
Grehlin inhibits
Leptin and adenosine induce sleep
Where are cholinergic cells located?
Pedunculopontine nucleus
What are the online nuclei active in REM sleep?
Cholinergic nuclei. (think ACEtylcholine responsible for ACE dreams)
why are people with sleep apnoea at a higher risk of stroke?
surge in sympathetic activity that happens after anoxia, increases BP and can rupture a cebreal blood vessel
How do TCAs promote sleep?
They exert blockade of histamine H1 receptors
What nerves leave through superior orbital fissure?
Occulomotor CN3
Trochlear CN4
Abducens CN6
and opthalmic branch of trigeminal CNV1
What nerve goes through the foramen rotendum?
CNV2 = maxillary nerve
What nerve goes through foramen ovale?
CNV3 = mandibular
What foramen does the facial nerve leave through?
Stylomastoid foramen
What nerve travels within the carotid sheath?
Vagus
What does a lesion to occulomotor nerve cause?
Down and out position, pupil dilates due to loss of parasympathetic innervation and also drooping of the eyelid
what does injury to trochlear nerve cause?
Rarely injured alone but double vision when looking down
What would injury to abducens present with?
Medial deviation and dilopia (double vision)
What is the path taken by CSF?
Lateral ventricles > Interventricular foramina > third ventricle > cerebral aqueduct > fourth ventricle
Of delusions, hallucinations, disorganised speech, disorganised behaviour and negative symptoms how many must you have to have shizophrenia?
At least two of them and one of them much be hallucinations, delusions or disorganised speech
What are the advantages of atypical anti-psychotics?
They better address cognitive symptoms and they have less extrapyramidal side effects
What are the main disadvantages of atypical side effects?
metabolic side effects - weight gain, dyslipideamia, T2D
also anticholinergic side effects eg dry mouth, constipation
What must be checked before starting someone on lithium?
Renal and thyroid function
Where do noradrenergic originate?
Locus coeruleus
What do the TCA drugs end with? (two things)
-pramines and -triptylines
eg clomipramine and amitriptyline
In DBS for depression what part of the brain would you target?
Subcallosal cingulate white matter - area 25
What is MAO of moclobemide?
selective and reversible MAOA inhibitor
Why can diclofenac lead to increased bleeding risk?
Bc it inhibits thromboxane
What tract is involved in occulomotor reflex, saccacidic eye movements and vestibular occular reflexes?
Medial vestibulospinal tract (head and eye coorindation, upright posture of head and neck)
What part of the brain directs the correct emotional or motor response in light of knowledge from past experience?
Medial prefrontal cortex (might be absent in people with autism)
What part of the brain works with the medial prefrontal cortex to play a role in reward mediated behaviours?
Orbitofrontal cortex
(remember it as it is near the eyes and the eyes see the reward)
Where does the globus pallidus external project to?
subthalamic nucleus
What pathway becomes dominant in PD?
Indirect pathway
(decreased inhibition of GPi which increases inhibition on the thalamus)
What does athetosis suggest a lesion to?
Striatum
(athetosis is slow writing movements)
What does ballismus suggest a lesion to?
Subthalamic nucleus
(violent involuntary flinging movements_
What are the main cells lost in Huntington’s?
Loss of medium size spiny neurons
What is the most common site of infarct in posterior circulation?
PICA - posterior inferior cerebellar artery
Damage to what part of the cerebellum can lead to vertigo, nystagmus and ataxic gait?
Vestibulocerebellum
Damage to what part of the cerebellum can lead to intention tremors, dysmetria and dysdiadochokinesis?
Neocerebellum
(as it is involved in motor planning)
Damage to what part of the cerebellum can lead to ataxic gait, hypotonia and pendular reflexes?
spinocerebellum
(called anterior lobe syndrome common in alcoholics)
What does medial vestibulospinal tract and lateral vestibulospinal tract do?
medial - balance of head on body
lateral - balance of body on ground
What tumour commonly causes flocculonodular syndrome?
Medulloblastoma in 4th ventricle
What are the semi circular canals full of?
endolymph
What movements does utricle detect?
horizontal
What movements does the saccule detect?
vertical movement
What is the central main connection for the occulomotor, trochlear and abducens nerves?
Medial longitudinal fasiculus
When is the COWS mneumonic correct?
for the nystagmus (referring to the fast component) but not for initial eye movement which is CSWO
What nerve does the caloric test test?
cranial nerve 8 - vestibulocochlear
If you still have the slow component of caloric reflex in both eyes intact what does this mean vs just in one eye?
Both eyes means the brainstem is intact
One eye only means there is an MLF lesion
What fibres carry the first sharp, stinging pain
A delta (myelinated)
Which spinothalamic tract is more associated with pain and temp?
Lateral
whereas anterior is mainly crude touch
Where does lateral STT project to to cause emotional aspect of pain?
anterior cingulate cortex and rostral insular cortex
Whereabouts is peri-aqueductal grey?
Midbrain (around cerebral acqueduct)
what is activated by PAG for descending pain modulation?
Locus coeruleus (contains noradrenergic neurons)
What are activated by serotonin and noradrenaline in descending pain modulation and what do they release?
Lamina II inhibitory interneurons
They release GABA and enkephalins to block noiceptor input
What channels do opioid receptors have an effect on to inhibit firing of sensory neuron?
Thye open Cl- ion channel and block Ca2+ channek
Why does meptazinol result in less resp depression?
It is a partial mu receptor agonist
Why is pethidine and morphone avoided in patients with kidney failure?
Bc its metabolites norpethidine M6G and can accumulate
Why can glial cell abnormalities play a role in epilepsy?
Bc glial cells clear glutamate through transporters like EAAT1 and EAAT2
How does levetiracetam work for seizures?
Binds to SV2A which inhibits presynaptic calcium channels modulating neurotransmittter release
What blood vessels come off at a right angle to middle cerebral artery?
Striate arteries
What is blood supply to corpus collosum?
Anterior cerebral artery (lesions = split brain)
Where is the blood in a subdural hematoma?
Between dura mater and arachnoid mater
What brain bleed can lead to xanthochromia and often resembles a STEMI on ECG?
subarachnoid hematoma
Which type of headache is only headache more common in men?
cluster headache
How do ditans work for migraine?
They are 5HT1F agonists (they dont cause vasoconstriction so can be used in people with cardiac issues)
What drugs are non specific to migraines but can be used as prophylactic treatment?
anti epileptics and beta blockers
What is the minimum and maximum GCS score?
Minimum = 3
Max = 15
what is considered moderate TBI score?
9-12
When would you perfom CT head?
If GCS is less than 13 at initial assessment or less than 15 at two hours post
What is normal intracranial pressure?
5-15mmHg
How are TBI patients sedated?
Propofol and benzos
What does systematic desensitization refer to?
The idea of replacing one response (anxiety) with another (relaxation)
What does operant conditioning use?
Rewards and punishments
Difference between pos and neg punishment?
pos - application of unpleasant stimulus
neg - removal of a pleasant stimulus
What is Bandura’s theory and how can we apply it?
theory people can change by watching other people cope - befriending interventions
What does Schacter-Singer Two Factor theory suggest?
That physiological arousal is interpreted in context of the experience to produce the emotion
When does Moro reflex disappear?
Between 3-6 months of age
Where does amygdala mainly project to in fear?
prefrontal cortex for behavioural response
hypothalamus and autonomic nuclei for autonomic fear responses
How is rhabdomyolysis blocked?
By dantrolene - muscle relaxant that lessens excitation-contraction coupling in muscle cells.
Where are CB1 and CB2 receptors located?
CB1 in CNS, CB2 - peripheral organs
What is acamprosate?
Helps reduce alcohol cravings, modulator of glutamatergic transmission
Difference between methadone and naltrexone?
Methadone is a mu opioid agonist - suppress withdrawal and naltrexone is an antagonist- used after detoxification
what cerebellar nuclei involved in motor execution and which in motor planning?
fastigial and interposed = motor execution
dentate = motor planning
What can mutations in MAPT cause?
frontotemporal dementia
What results in aggregation of Tau?
Its hyperphosphorylation
What synapses are particularly affected by neurotoxic alpha beta oligomers?
cholinergic synapses
What can interact with alpha beta peptide and promotoe amyloid fibril formation?
acetylcholinesterase
How can memantine work for AZD?
It is an NMDA receptor antagonist, blocks the ion channel and decreases glutamate mediated neurotoxicity
Which neurons increase their activity during REM sleep to same level as alert waking?
Cholinergic neurons
What do anterior and posterior hypothalamic lesions cause?
anterior = insomnia
posteior = hypersomnia
think towards front of lecture theatre everyone is awake but towards the back they are sleepy
What is nucleus reticularis paragigantocellularis?
Involved in descending pathyway of pain, projects to nucleus raphe magnus
What do the neurons of the tuberomamillary system release?
Histamine. They are tonically active during wakefulness
What is the brain’s sleep promoting region?
Ventrolateral preoptic nucleus
What stage of sleep is vital for maintenance and repair?
slow wave sleep
What stage of sleep does somnambulism occur during?
slow wave sleep
What neurons are involved in sleep?
GABA and galanin
Which waves are present during normal wakefulness and then which when youre awake but relaxed?
normal wakefulness= beta waves
awake and relaxed = alpha waves (slower)
Which receptors do buspirone, ipsapirone act on? (anxiety treatment)
5HT 1A (partial agonists)
What subunits of GABA receptors are to do with what effect?
alpha1 = hypnotic
alpha2= anxiolytic
Damage to which part of the brain causes locked in syndrome?
Ventral pons - causes interruption to corticospinal and corticobulbar tract
When is vegetative state deemed permanent?
12 months after traumatic injurt
3 months after non traumatic injurt
What drugs are used in treatment resistance schizoprhenia?
Clozapine - only drug that seems to work when resistant
How does baclofen work for pain?
GabaB receptors agonist
How does ketamine work for pain?
It is an NMDA glutamate receptor antagonist
What toxic metabolite can build up if using opioids and have renal failure
M6G metabolite
first line for trigeminal neuralgia?
carbamazepine
