lecture 10 Flashcards
65% of epileptic cases are cause by what?
idiopathic/cryptogenic
some of the people at risk for epilepsy?
mental retardation, cerebral palsy, autism and storke
epileptic patients are at risk for what in the mouth because of their medications?
gingival hyperplasia
what shrinks in the brain of people who have epilepsy?
hippocampus and temporal lobe
if patient has seizure, what should you be sure to pay attention to?
when it started, anything longer than 3 minutes may cause brain damage
what can be used if pt has seizure?
midazolum
1/3 of known genes linked to epilepsy encode what ?
ion channels
class 1 drugs for epilepsy do what?
increase GABA transmission
GABAa receptors mediate mostly what?
fast synaptic inhibition
phenobarb, benzos, and topiramate all act at what level?
GABAa receptor postsynaptic
tiagabine work where
GABA transporter
vigabatrin and valproate work where?
GABA breakdown
what does vigabatrin do?
inhibits GABA-transaminase which breaks down GABA. works to increase amount of GABA.
what is the drug of choice for myoclonic seizures? (juvenile)
valproate
explain valproate
reversible gaba T inhibitor by inhibiting histone deacetylase. metabolism through glucuronide, associated with hepatic toxicity
explain tiagabine
GABA reuptake inhibitor, metabolism through P450 (important to be carful on cocktail of drugs). common side effects: confusion, difficulty speaking, mild sedation
topiramate is structurally related to what?
fructose
explain topiramate
GABAa receptor positive modulator, and inhibits neurotransmission through kainite and AMPA receptors. metabolism 30% liver and rest secreted unchanged
class 2 drugs for epilepsy do what?
slow rate of recovery of sodium channels from inactivation
what is the most widely used anti seizure agents?
class 2, phenytoin and carbamazepine to slow rate of recovery of sodium channels
phenytoin and carbamazepine only used for what kind of seizures?
partial and tonic clonic generalized
important side effects of phenytoin
gingival hyperplasia mostly in children. may affect bone support of teeth and tooth position. xerostomai, postoperative bleeding
carbamazepine should not be taken with what?
pain relievers and erythromycin
explain some things about oxcarbazepine.
slow rate of sodium channel recovery. also used in treatment of bipolar disorder.
Lamaotrigine can cause what
steves johnson syndrom-rash
class 3 drugs for epilepsy do what?
reduce calcium flow through t-type calcium channels
t-type calcium channels play important role in burst firing of action potentials where?
thalmus
valproate does what 3 things?
GABA transaminase inhibitor, inhibits t-type calcium channels, inhibits histone deacetylase
valproate is secondary choice for what kind of seizures?
absence
explain ethosuximide
t-type calcium channel blocker. lacks hepatotoxicity of valproic acid. 80% metabolism is hepatic. syrup form
gabapentin major use to relieve what
neuropathic pain
gabapentin made to mimic what? how does it work?
mimic structure of GABA, doesn’t work on GABAa receptor. works by inhibition of voltage gated calcium channels
best drug for partial seizure?
lamotrigine, carbamazepie, pheyntoin
best drug for tonic clonic
valproate
best drug for absence seizure
ethosuximide
diazepam and lorazepam are what
positive modulators of gab a receptor
vigabatrin involved in what
gabaeric transmission
problem with anti convulsive drugs
p450 interactions
