Anticonvulsants

Question 0

Carbamazepine

Answer 0

-inhibits voltage-gated Na channels (inhibits AP propagation)
Seizure types
-partial seizures
-tonic-clonic 
ADE
-*diplopia
-*ataxia
-aplastic anemia and agranulocytosis (leukopenia)
Drug interactions
-other anticonvulsants

Question 1

Phenytoin

Fosphenytoin

Answer 1

-inactivated voltage gated Na channels (inhibits AP)
-DEC glutamate & INC GABA release
Seizure types
-generalized tonic-clonic seizures
-partial seizures
ADE
-nystagmus=dizzy eye twitch
-diplopia=double vision
-gingival hyperplasia
-ataxia
-*hirsutism=male hair growth pattern in women
-**severe cardiovascular risk
Drug interactions
-carbamazepine
-topiramte

Question 2

Valproic Acid

Divalproex

Answer 2

-inhibits voltage-gated Na channels (inhibits AP propagation)
-inhibits T-type Ca++ channel–> INC GABA in brain (inhibitory)
Seizure type
-absence seizures
-generalized tonic-clonic seizure
-control certain (tonic-clonic seizure)
ADE
-nausea
-vomiting
-GI complaints
-Idiosyncratic hepatotoxicity
-*severe cardiovascular risks
Drug interactions
-inhibits metabolism of several drugs (phenytoin, carbamazepine, and phenobarbital) so they last longer
-displace phenytoin from plasma proteins
Contraindication
-pregnant women (can cause *spina bifida in child)

Question 3

Benzodiazepines:
*Lorazepam
Diazepam
Midazolam

Answer 3

-Facilitate action of GABA
-INC frequency of Cl- channel opening
Seizure type
-status epilepticus
ADE
-sedation
-tolerance/dependence
-anterograde amnesia: surgery & date rape drugs

Question 4

Barbiturates:

Phenobarbital

Answer 4

-facilitating action of GABA
-INC duration of Cl- channel opening
Seizure type
-partial seizures
-tonic-clonic seizures
-every seizure type (attacks hard to control)
ADE
-sedation
-respiration and cardiac depression
-tolerance
-dependence
-cognitive dysfunction
Contraindications
-Porphyria disorder - heme is not properly made
Drug interactions
-other sedatative-hypntics (alcohol)/ CNS depressants

Question 5

**Flumazenil

Answer 5

-GABAa receptor antagonist
-antagonist to benzodiazepines (antidote for OD or benzodizepine induced CNS depressant effects)
ADE
-agitation
-confusion
-dizziness
-nausea

Question 6

Ethosuximide

Answer 6

-blocks thalmic T-type Ca++ channels-->DEC current
Seizure type
-Absence seizure
ADE
-GI distress
-lethargy
-HA
-uticaria - hives
Drug interactions
-valproic acid - DEC in metabolism, INC in steady-state concentration

Question 7

Levetiracetam

Keppra

Answer 7

MOA
-unknown
-binds to synaptic vesicular protein SV2A
-may modulate - DEC glutamate/ INC GABA release
Seizure type
-*Adjunctive Therapy
-partial seizures (adults and children >4 yo primary seizures)
-myoclonic seizures of juvenile myoclonic epilepsy
-primar generalized apilepsy (children >6yo)