neurological Flashcards
madopar
L-DOPA/levodopa + benseraizde
antiparkinsonian agent - dopaminergic drug for parkinsons
sinemet
levodopa + carbidopa
antiparkinsonian agent
how does sinemetwork?
levodopa changes to dopamine in the brain - helps control movement
carbidopa prevents breakdpwn of levodopa in bloodstream
how does madopar work?
levodopa is changed to dopamine in the brain
benserazide allows more Ldopa to get to brain before changed to dopamine
indications for sinemet
parkinsons disease
contraindications for sinemet
elderly with existing cognitive or psychiatric disease - risk of confusion and hallucinations
caution in CVD - hypotnesion risk
side effects of sinemet
nausea drowisness confusion hallucinations hypotension dyskinesia at beginning of dosage interbal on-off effect
interactions of sinemet
not combined with antipsychotics or metoclopramide due to contraictory effects on dopamine receptos
levodopa always give with??
why?
dopa decarboxylase inhibitor (carbidopa) to reduce conversion to dopamine outside tje brain
inidcations for madopar
parkinsons disease
contraindications of madopar
elderly with existing cognitive or psychiatric disease
sife effects of madopar
nausea drowsiness confusion hallucinations hypotension dyskenesia at beginning of dosage interval - on-off effect
interactions of madopar
not used with antipsychotics or metoclopramide due to effects on dopamine receptors are contradictory
phenytoin
antiepileptic/anticonvuslant
how does phenytoin work?
phenytoin reduces neruonal excitability and electrical conductance among brain cells- inhibits seizure activity
bind to neuronal Na+ channels in inactive state - promoting inactivity and preventing influx
indications of phenytoin
control seizures in status epilepticus where benzodiazepines are ineffective
reduce freq of generalised or focal seizures in epilepsy
contraindications of phenytoin
margin between therapeutic and toxic dose is low
dose reduced in hepatic impariemtn
not in pregnancy - or take high dose folic acid
side effects of phenytoin
change in appearance - skin coasening, acne, hirtusim, gum hypetrophy
neurological effects - cerebellar toxicity and impaired cognition
hypersensitivity reactions to
toxicity- cdeath thorugh cardiovascular collapse and repsiratory depression
interactions of phenytoin
reduces efficact of drugs metabolised by P450 enzymes
Efficacy of phenytoin is reudced by drugs that lower seizure threshold - SSRIs, tricyclics, antihyschocitcs, tamadol
carbamazepine
antiepileptic/anticonvulsant
how does carbamazepine work?
inhibits neuronal sodium channels - stabilising membrane potentials and reducing neuronal excitability
= inhibit spread of seizure activity in epilepsy, controls neruralgic pain
Indications for carbamazepine
epilepsy - first choice for focal seizures with and without secondary generalisation
trigeminal neuralgia- first line to control pai and reduce freq of attakcs
bipolar disorder fpr prophylaxis in paients reisstant to or intolerant of other meds
contraindications of carbamazepine
pregnancy - high dose folic acid for conception
antiepileptic hypersensitivity syndrome is contraindication
caution in hepatic, renal or cardiac disease
interactions of carbamazepine
durgs metabolised by P450 enzymes
efficacy reduced by durgs that lower seizure threshold - SSRIs, tricyclics, antipsychotics, tramadol
side effects of carbamazepine
GI upset - neausea and vomiting
neuroligical effects - dizziness and ataxia
hypersensitivity - rash
sodium valproate
antiepile[tic/anticonvulsant
how does sodium valproate work?
inhibitor of sodium channels - stabilise resting membrane potential and reduce neuronal excitability
increases brain content of GABA - principal inhibitory enurotransmitter = regulates neuronal excitability
indications for sodium valproate
epilepsy - first choice drug of generalised or absence seizures and option for focal seizures
bipolar disorder - acute treatment of manic episodes and prophylaxis against reucrrance
contraindications of sodium valproate
pregnancy
hepatic impairment and renal impairment
side effects of sodium valproate
GI upset - nausea, gastric iiration, diarrhoea
neurological and psychiatric effects – tremor, ataxia, behavioural disturbances
thrombocytopenia
hypersensitivity - hair loss
rare, lifethreatneing idiosyncratic adverse efffects - severe liver injury, pancreatitis, bone marow failure, antiepileptic hypersensitivity syndrome
possible interactions of sodium valproate
drugs metabolised by P450 enzymes
efficacy lowered by drugs that decrease seizure threshold
do not drive if got epilepsy unless seizure free for ___ months or sleep only seizures for ___ years
dotn drive for __ months after stopping or changing treatment
12 months
3 years
6 months
lamotrigine
anti epileptic/convulsant
how does lamotrigine work?
sodium channel blocker, leading to stabilisation of neuronal membranes
blocks some calcium channels
indicatiosn fo lamtrigine
on own or in combination to treat focal and generalised seizures, inc tonic-clonic seizures
seizures associated w lennox-gastaut syndrome
absent seizures in children and prevention of depressive episodes associated with bipolar disorder
side effects of lamotrigine
nausea, vomiting, diarhhoea, dry mouth
aggression, agitation, headache, drowsiness, dizziness, tremor, insomnia, ataxia
back pain,arthralgia, nystag,mus, diplopia, blurred vision, rash
interactions of lamtrigine
carbamazepine - rasies plasma concentration of an active metaoblite of it
interacts with all other antiepileptics
levetiracetam
anti-epileptic/convulsant
how does levetiracetam work?
reduces abdnormal conduction signals in brain by binding to syndaptic vesicle glycoprotein 2A
indications for levetiracetam
on own or in combination to treat focal seizures with or without secondary generalisation
adjuvant therapy of myoclonic seizures in patints with juvenile myoclonic epilepsy and primary generalised tonic-clonic seizures
sometimes used in myoclonic or absent seizures (not licensed for these)
what to not do when taking levetiracetam
avoid abrupt withdrawal
side effects for levetiracetam
anorexia, abdo pain, nausea, vomiting, dyspepsia, diarrhoea, cough, nasopharyngitis, vertigo, drowsiness, ataxia, convulsion, dizziness, headache, tremor, malaise, aggression, depression, insomnia, anxiety, irritability, rash
interactions of levetiracetam
increase in plasma conc of carbamexapine and methotrexate
