Epilepsy

Question 1

Phenytoin

Answer 1

Grand-Mal: Voltage gated Na (blocks by stabalizing inactivated state use-dependant). Zero-order, CYP450 inducer.

Question 2

Carbamazepine

Answer 2

Grand-Mal: Voltage gated Na (blocks by stabalizing inactivated state use-dependant). ADR: CYP450 incuced, hepatotoxcity, anemia.

Question 3

Valproate

Answer 3

Broad Spectrum, Grand-Mal, and Absence: Na block, T-type block and increased GABA. It actually, inhibits the metabolism of most AEDs.
Black Box Warning: Hepatic failure, pancreatitis, teratogenic (all lead to death).

Question 4

Levetiracetam

Answer 4

Grand Mal (tonic clonic) and Partial: impairs presynaptic Ca channels, and prevent vesicle formation. No CYP450 metabolism, minimal DDI.

Question 5

Phenobarbital

Answer 5

Broad Spectrum, barbituate (GABA-Cl prolonger)

Question 6

Diazepam

Answer 6

Broad Spectrum, BZD (GABA-Cl).

Question 7

Divalproex

Answer 7

Broad Spectrum

Question 8

Ethosuximide

Answer 8

Absence, Blocks T-type Ca Channels (prevents firing when not hyperpolarized by thalamus).

Question 9

Status epilepticus

Answer 9

BZD first: Diazepam, Lorazepam, Midolazam (All BZD GABA-Cl).
Then: phenytoin.
Then (if refractory): phenobarbital.
Finally (if not working): propofol to induce anesthesia.

Question 10

Lamotrigine

Answer 10

VSSC and VSCC blocker: 1st line for general AND partial. (better tolerated than phenytoin and carbamazapine). Don’t know why this isnt on drug list, but should be.