Antiseizure Flashcards
What is the mechanism of action of Carbamazepine and its clinical use?
Stablizes inactive state (keep hyperpolarized) of voltage gated Na+ channels
- less Na+ means less firing of AP
- Can also be used in Neuropathic pain
- sometimes thought to be a Gaba agonists as well
CU: partial/focal and 2’ generalized tonic-clonic seizure
What are the antiseizure meds?
- Carbamazepine
- Ethosuximide
- Levetireacetame
- Phenytoin
- Topiramate
- Valproic acid
- Phenobarbital
- Diazepam and lorazepam
- Gabapentin
What is the mechanism of action of Ethosuximide?
Blocks Ca2+ channels and disrupts pacemaker activity
CU: Primary treatment for absence seizures
What is the mechanism of action of Levetiracetam?
affects synaptic vesicle protein SV2A which leads to decreased glutamate release and increased GABA release.
CU: Primary treatment for focal, primary/2’ generalized tonic-clonic and myoclonic
What is SV2A protein?
It is a protein found on most vesicle and it positively binds vesicle fusion.
What is the mechanism of action of Phenytoin?
Prolongs inactivation phase of Voltage gated Na+ channels and prevents rapid firing of AP
- may also decrease glutamine
CU: partial and 2’ generalized tonic-clonic seizures
What is the mechanism of action of Topiramate?
- Increased inactivation of voltage gated NA+ channels,
- blocks presynaptic VG CA2+ channels
- Enchanes GABAa R currents
CU: focal and primarily generalized tonic-clonic seizures
what are some adverse affects of antiseizures meds?
- N,V, ataxia, dizzinesss, drowsiness, fatigue and HA
- Rash which can complicate to SJS
- Anemia, agranulocytosis, and cytopenias
- Liver E induction or inhibition
What is the mechanism of action of Valproic acid
Decreases firing
- blocks Na and NMDA
- decreased GABA reuptake
- reduces flow through Ca2+ channels
What is the mechanism of action of phenobarbital?
increase duration of GABAa r opening and depressed excitatory glutamate actions
What is the mechanism of action of diazepam/lorazepam?
increases frequency of GABAa receptor opening
What is the mechanism of action of Gabapentin
Inhibits voltage gated Ca2+ channels and thus inhibits its entry in to the presynaptic neuron.
