Anticonvulsants Flashcards
refractory epilepsy
after trying 2 AEDs, overall seizure-free rates with subsequent meds is reduced to 4%
33% of epilepsy patients fit this criteria
1st generation AEDs
Enzyme inducers:
- phenobarbital
- phenytoin
- carbamazepine
Enzyme inhibitor:
- valproate
phenytoin
most widely used AED
enzyme inducer
inhibits rapid firing Na+ channels
90% bound to plasma protein - but this can be disrupted and dramatically increase the free/active amount
AEs: CNS sedation - drowsy, ataxia, confusion, insomnia, nystagmus, gum hyperplasia, hirsutism
status epilepticus treatment
carbamazepine
use for neuropathic pain
causes hyponatremia, agranulocytosis, aplastic anemia
stimulates met of itself and other drugs
valproate/valproic acid
can use for bipolar and migranes
valproate/valproic acid
1st line for epilepsy
rare but severe hepatotoxicity
neural tube defects/spina bifida
can use for bipolar and migranes
ethosuximide
for ABSENCE seizures
blocks T type Ca++ channels in thalamus
gabapentin
use for neuropathic pain
benzodiazapines
increase the FREQUENCY of GABAa Cl- openings
rescue meds as IV in SE
Felbamate
AE: hepatic failure, aplastic anemia
Lamotrigine
AE: Stevens-Johnson syndrome!!!
safe in pregnancy
use for bipolar
Felbamate
3rd line, rare bc toxicity
AE: hepatic failure, aplastic anemia
Zonisamide
broad-spectrum
AEs: kidney stones (must drink a LOT of water)
Lyrica/Pregabalin
reduces NT release by acting on VGCa++C
use for neuropathic pain
AE: appetite increase, weight gain
vigabatrin
4th line
AE: significant, irreversible visual field constriction
