Antiseizure drugs [3]

Question 1

Seizure vs convulsion

Answer 1

seizure: excessive neuronal discharge
- where antiseizure drugs target - broader

Convulsion: violent involuntary contraction due to excessive electrical activity

Question 2

Drug to tx partial seizures (focal)

Answer 2

Levetiracetam

(carbamazepine, lamotrigine)

note* simple and complex seizures fall under partial seizures

• more difficult to tx than generalized seizures

Question 3

Drugs to tx generalized seizures

Answer 3

1. Absence:
   Ethosuximide, Valproate
2. Grand mal (tonic clonic)
   Levetiracetam (keppra), Valproate, Phenytoin, Carbamazepine
   (Lamotrigine)

Question 4

Broad spectrum antiseizure med

Answer 4

Phenobarbitol
Diazepam (valium)
Valproate (depakene)
Divalproex (depakote)

Question 5

Tx for status epilepticus

Answer 5

Diazepam (valium) - IV
Lorazapam (ativan)
Midazolam (versed)

ADRs: somnolence

Question 6

Mechanism of Generalized Tonic-clonic vs Generalized Absence seizures

Answer 6

Generalized Tonic-clonic:

• intiation → loss of GABA tone
• propagation → loss of GABA tone over large areas, plus ↑ response to glutamate and Na+ channel excitation

Generalized Absence seizures
- oscillatory stimulation of thalamic-cortical circuitry - activation of low threshold T- type Ca2+ channels

Question 7

Why arent Z drugs good against convulsions (bc they do have anti-convulsant properties)

Answer 7

bc you are asleep (hypnotic) before you get the anticonvulsant effects
- BDZ are good

Question 8

MOA

• Ethosuximide
• Lamotrigine
• Levetiracetam

Answer 8

Ethosuximide
- blocks the low-threshold T-type Ca2+ channels in thalamocortical pathways

Lamotrigine

• blocks high voltage VSCC (that is involved in reg of Glu release)
• blocks VSSC (suppress repetitive APs)

Levetiracetam

• Inhibits synaptic vesicle protein SV2A
• impairs Ca2+ mediated NT release

Question 9

MOA 
Valproic acid
Diazepam
Phenytoin
Carbamazepine

Answer 9

Valproic acid
- enhancement of Gaba activity

Diazepam
- enhancement of GABA activity

Phenytoin
- blocks VSSC (suppress repetitive AP)

Carbamazepine
- blocks VSSC (suppress repetitive AP)

Question 10

Which antiseizure can cause gingival hyperplasia. List its MOA

Answer 10

Phenytoin

- blocks VSSC (suppress repetitive AP)

Question 11

Agranulocytosis

Answer 11

Clozapine

Question 12

1st line tx in generalized tonic clonic

Answer 12

Levetiracetam (keppra)

others: Valproate, Phenytoin, Carbamazepine
(Lamotrigine)

Question 13

Do we have a higher incidence of anxiety disorders or major depressive disorders?

Answer 13

anxiety

Question 14

incidence of bipolar mania and depression

Question 15

Black box warnings for Carbamazapine and Valproate (depakote)

Answer 15

Hepatic failure –> death

- monitor Liver Function Test

Question 16

Classic enzyme inducer

Answer 16

phenobarbital
Broad spectrum antiseizure med
Good for difficult to tx seizures

(carbamazepine and phenobarbital also induce enzymes)

Question 17

Anticonvulsive agents will result in additive CNS depression (increased somnolence) when given with what?

Answer 17

Opiod analgesics

(these are all anticonvulsives:

• phenytoin
• carbamazepine
• Phenobarbital
• Diazepam
• Levetiracetam