ANTISEIZURE DRUGS

Question 1

GENERAL MOA of the Antiseizure Drugs? (3)

Answer 1

o Modification of ionic conductance (mostly sodium) and
presynaptic transmitter release (SV2A)
o Enhancement of GABAergic (INHIBITORY) Transmission
o Diminution of excitatory (usually GLUTAMATERGIC)
transmission

Question 2

Side effects of Phenytoin,
Fosphenytoin,
Phenacemide

Answer 2

MNEMONICS: Phenytoin

cyP-450 induction
Hirsutism
Enlarged gums (gingival hyperplasia), Nystagmus
Yellow-brown skin
Teratogenicity (fetal
hydantoin syndrome)
Osteopenia
Inhibited folate absorption
Neuropathy

Question 3

DOC for trigeminal neuralgia

Answer 3

Carbamazepine

Question 4

most teratogenic AED

Answer 4

Valproic Acid

Question 5

MOA Valproic Acid

Answer 5

• Also blocks NMDA and increases GABA

Question 6

MOA Lamotrigine

Answer 6

Also blocks Ca channels, decreases glutamate

Question 7

Notable SE of Lamotrigine?

Answer 7

Rash and SJS/TEN

Question 8

• AED with the most anti-seizure MOAs
  (also acts on K, Ca, GABA, AMPA-glutamate,
  and is a weak carbonic anhydrase inhibitor)
• Also used for Lennox-Gestaut & West
  syndrome
• Causes sleepiness, cognitive slowing,
  confusion
• Urolithiasis (carbonic anhydrase activity)

Answer 8

Topiramate,
Felbamate

Question 9

MOA ETHOSUXIMIDE [C], PHENSUXIMIDE, METHSUXIMIDE

Answer 9

Decreases Ca2+ currents (T-type) in thalamus
Ethosuximide reduces low threshold T-type Ca2+
currents in the thalamic neurons

Question 10

Absence seizures (DOC)

Answer 10

ETHOSUXIMIDE [C], PHENSUXIMIDE, METHSUXIMIDE

Question 11

Blocks Ca2+ α2δ channels. Decrease glutamate
release. Inhibits neuronal discharge from seizure foci.

Answer 11

GABAPENTIN [C], PREGABALIN [C]

Question 12

Inhibits GABA reuptake via GAT-1

Answer 12

TIAGABINE

Question 13

Irreversibly inhibits GABA transaminase

Answer 13

VIGABATRIN

Question 14

SE of VIGABATRIN

Answer 14

Permanent bilateral vision loss

Question 15

Selectively binds synaptic vesicular protein SV2A →
selectively inhibiting hypersynchronization of
epileptiform burst firing; Modifies synaptic release of
glutamate and GABA. Inhibits Ca2+ channels also

Answer 15

LEVETIRACETAM, BRIVARACETAM

Question 16

DOC fr Generalized Tonic Clonic Seizures?

Answer 16

Lamotrigine, Valproic acid

Question 17

DOC for Focal Seizures

Answer 17

Lamotrigine, Phenytoin,
Carbamazepine, Levetiracetam

Question 18

Absence Seizures DOC

Answer 18

Ethosuximide,

Question 19

Myoclonic and Atypical
Absence Syndromes DOC

Answer 19

Valproic Acid, Lamotrigine,
Topiramate

Question 20

AED used also for Acute Mania

Answer 20

Valproic Acid

Question 21

AED used also for Hyperbilirubinemia?

Answer 21

Phenobarbital

Question 22

AED used also for post herpetic neuralgia?

Answer 22

GABAPENTIN

Question 23

causes Fetal hydantoin syndrome?

Answer 23

Phenytoin

Question 24

Causes spina-bifida NTD and craniofacial anomalies?

Answer 24

Carbamazepine

Question 25

causes spina bifida and NTDs?

Answer 25

Valproic Acid

Question 26

Most common SE of Hydantoins (Phenytoins)

Answer 26

Diplopia-Ataxia

Question 27

MC SE of Branched Chain FA or Valproic Acid?

Answer 27

GI UPSET

Question 28

MC SE of Barbiturates?

Answer 28

Sedation

Question 29

Causes Gingival Hyperplasia?

Answer 29

Phenytoin

Question 30

Causes SJS?

Answer 30

Carbamazepine

Question 31

Causes acute intermittent porphyria?

Answer 31

Barbiturates

Question 32

CYP 450 effects of Phenytoin, carbamazepine and Phenobarb?

Answer 32

Inducers

Question 33

CYP 450 effects of valproic acid?

Answer 33

Inhibitor