antiepileptics

Question 1

paroxysmal depolarization shift (PDS)

Answer 1

membrane potential doesn’t return rapidly to normal
prolonged Ca2+ dependent depolarization
results in several Na+ mediated APs
followed by long period of hyperpolarization

Question 2

feed-forward inhibition

Answer 2

inhibits over-activation (prevents spike)

Question 3

feedback inhibition

Answer 3

excites interneurons to prevent neighboring neurons from firing (prevent spread of seizure)

Question 4

interictal period

Answer 4

“inhibitory surround”

abnormal activity is confined to seizure focus by afterhyperpolarization

Question 5

CNS excitation

Answer 5

Glu, Asp

inward Na+ and Ca2+

Question 6

CNS inhibition

Answer 6

GABA

inward Cl-
outward K+

Question 7

inhibit Na+ channel

Answer 7

focal, status epilepticus

modulate gating mechanism (fast)
bind inactivated subunits (slow)

Question 8

inhibit Ca2+ channel

Answer 8

all except LG

T-type (absence) - decrease slow depolarization

N/L-type - decrease excitatory NT

Question 9

GABA-A receptor agonist

Answer 9

myoclonic, GL, status epilepticus

Question 10

barbiturates MOA

Answer 10

status epilepticus

increase duration of Cl- channel opening

Question 11

benzodiazepines MOA

Answer 11

increase affinity of GABA for receptor

Question 12

GABA uptake inhibitors

Answer 12

adjunct for focal seizures

Question 13

tiagabine

Answer 13

inhibit GABA transporter

focal

Question 14

GABA transaminase inhibitors

Answer 14

adjunct for seizures

Question 15

vigabatrin

Answer 15

inhibit degradation of GABA by GABA transaminase

broad spectrum

Question 16

SV2A ligands

Answer 16

adjunct for seizures

release GABA

Question 17

levetiracetam

Answer 17

inhibits vesicular release of Glu

broad-spectrum:
myoclonic (adjunctive)

Question 18

Glu antagonist

Answer 18

focal, generalized

block NMDA/AMPA receptors

Question 19

selection of AED

Answer 19

1) seizure type
2) epilepsy syndrome
3) pharmacokinetic profile
4) adverse effects

Question 20

acute, dose-related SE

Answer 20

neurologic/psychiatric
GI
weight change
appetite change

Question 21

acute, serious SE

Answer 21

renal stones, anhydrosis, acute closed angle glaucoma, hyponatremia, leukopenia, thrombocytopenia

Question 22

idiosynchratic SE

Answer 22

rash/exfoliation
Stevens-Johnson Syndrome
hematologic damage

Question 23

chronic SE

Answer 23

osteoporosis (vit D deficiency)
teratogenesis (folate deficiency)
altered CT metabolism/growth
neuropathy
cerebellar degeneration
sexual dysfunction

Question 24

strong inducers

Answer 24

increase clearance

decrease concentration

Question 25

strong inhibitor

Answer 25

decrease clearance

increase concentration

Question 26

phenytoin

Answer 26

inhibits Na+ channel

focal

Question 27

fosphenytoin

Answer 27

inhibits Na+ channel

Question 28

carbamazepine

Answer 28

inhibits Na+ channel
focal

auto-induction

Question 29

oxycarbazepine

Answer 29

inhibits Na+ channel
focal
mild inducer/inhibitor

Question 30

lamotrigine

Answer 30

broad spectrum

inhibits Na+ channel (adjunct)

Question 31

ethosuximide

Answer 31

inhibits T type Ca2+ channel

absence

Question 32

valproate

Answer 32

inhibits T type Ca2+ channel
inhibits N/L type Ca2+ channel
Glutamate decarboxylase activation

broad spectrum:
tonic-clonic
absence
myoclonic

Question 33

topiramate

Answer 33

inhibits N/L type Ca2+ channel
Glu receptor antagonist

broad spectrum:
focal
tonic-clonic

mild inducer/inhibitor

Question 34

ezogabine

Answer 34

opens K+ channel

focal

Question 35

open K+ channel

Answer 35

slow vg K+ channels (M currents)

focal seizures

Question 36

clonazepam

Answer 36

benzodiazepine

myoclonic
Lennox-Gastaut Syndrome

Question 37

gabapentin

Answer 37

Glutamate decarboxylase activation

focal

Question 38

pregablin

Answer 38

Glutamate decarboxylase activation

focal

Question 39

lacosamide

Answer 39

focal