Unit 2- Anticonvulsants Flashcards
Anticonvulsants
Reduce frequency of neuron firing to block seizure initiation and propagation
Anticonvulsant Metabolism
Metabolized too quickly in dogs, cats metabolize slowly and poorly
Anticonvulsant MOA
Activate GABA Cl- channels, bind GABA A receptor, inactivate Na+ and Ca++ conductance
Anticonvulsant Adverse Effects
Rapid cessation effect, liver and serum enzyme induction, and hepatotoxicity in dogs
Barbiturate MOA
Phenobarbital, Pentobarbital, Primidone, activate GABA gated Cl- channels
Benzodiazepine MOA
Diazepam, Midazolam, Clonazepam, and Lorazepam GABA A receptor agonists
Hydantoin MOA
Phenytoin targets sodium channels
Valproic Acid MOA
Acts via Cl- channels
Gabapentin MOA
Synthetic GABA analog inhibiting voltage gated Ca++ channels
Levatiracetam MOA
Binds to synaptic vesicle protein 2A
Felbamate MOA
Unknown
Zonisamide MOA
Inhibits Na+ and Ca++ channels
GABA
Major inhibitory neurotransmitter, controls fear and anxiety, inhibits activity of neurons
Phenobarbital
Produces anticonvulsant effect at lower doses than those needed to cause sedation
Phenobarbital Uses
Long term seizure control
Phenobarbital Adverse Effects
Sedation, PU/PD, polyphagia, dogs develop a tolerance to sedative effects