Anti Seizure Meds

Question 0

Risk with all anti seizure drugs

Answer 0

• depression and increased suicidality
• microsomal enzyme interactions
  ~ CYP3A4 inducers: phenytoin (phospho), phenobarbital,
  carbamazepine, oxcarbazepine and topiramate
  ~ CYP2C9 inhibitors: valproate
  ~ CYP2C1 inhibition: topiramate

Question 1

Absence trt

Answer 1

Treated with Ca channel drug (ethosuximide, valproic acid, clonezapam)

Question 2

Phenytoin: MOA, use, consideration

Answer 2

• 0th order kinetics (only fosphenytoin used anymore)
• used for all types sans absence
• MOA: prolong Na channel inactivation
• many CYP enzymes
• highly protein bound: hymoalbuminemic -> increased toxicity

Question 4

Azapines (carbam, oxam)

Answer 4

• MOA: decreases Na influx
• Indication: Tonic clonic, partial complex, neuropathic pain, bipolar disorder, paresthesia, PTSD
• SE: Diplopia, ataxia, cognitive dysfunction, rare aplastic anemia and hepatotoxicity
• carb: lots of microsomal interactions
• ox: CYP3A4 only
• ox can result in hyponatremia

Question 5

Lamotrigine

Answer 5

• MOA: Na + Ca channel
• partial, tonic-clonic, bipolar
• SE: dizziness, ataxia, visual disturbances, Stevens-Johnson’s
• lots of drug interactions

Question 6

Topiramate

Answer 6

• MOA: Na channel modulation, potentiates GABA/blocks AMPA
• partial, binge eating, PTSD
• SE: dizziness, drowsiness, ataxia, psychomotor slowing, memory impairment, weightloss, myopia
• weightloss SE exploited pharmacologically
• induces 3A4, inhibits 2C19 and excreted unchanged

Question 7

Valproic acid

Answer 7

• blocks t type Ca channels, and acts on Na
• treats everything but bipolar
• SE: hepatotoxicity, nausea, tremor, weight gain and hair loss
• inhibition of 2C9; induction of 2A6
• NOT for kids under 2 (caution in kids under 6)
• NTDs

Question 8

Gabapentin

Answer 8

• MOA: Voltage gaited Ca channel blockers
• adjunct: neuropathic pain, parasthesis, PTSD, mania
• excreted unchanged in urine, FEW INTERACTIONS
• SE: sedation, dizziness, ataxia, nystagmus, mood disorders in kids

Question 9

Pregabalin

Answer 9

• MOA: binds to N-type Ca channels
• adjunct for partial seizures; neuropathic pain, fibro
• similar to gabapentin with less interactions and side effects

Question 10

Levetiracetam

Answer 10

• MOA: not listed
• excreted in urine, few interactions
• SE: sedation, dizziness, weakness and ataxia
• rare side effects irritability, hallucinations, psychosis

Question 11

Benzodiazepines

Answer 11

• MOA: GABA enhancement
• IV or rectal benzos for STATUS EPTILEPTICUS
• SE: sedation (hyperactivity in kids) and tolerance
• Clonazepam for absence; less sedating at anticonvulsant doses

Question 12

Phenobarbital

Answer 12

• tonic/clonic, partial
• SE: Severely sedating, cognative dysfunction, tolerance, dependance, nystagmus, ataxia, osteomalacia (chronic use) decreased D and K,
• Cind: porphyrias

Question 13

Ethosuximide*

Answer 13

Specific for absence

Question 14

Lacosamide*

Answer 14

• cardiac effects

- C - V controlled substance

Question 15

Primidone*

Answer 15

Cognative impairment

CYP inducer

Question 16

Rufinamide*

Answer 16

• Lennox-Gestaut epilepsy only

Question 17

Tiagabine *

Answer 17

Adjunct

Question 18

Vigabatrin

Answer 18

Renal excretion
few drug interactions
Visual impairment
- trt for west syndrome

Question 19

Zonisamide

Answer 19

Sulfa drug
Nephropethiasis (more risk than with topiramate)
SJ syndrome

Question 20

Ezogabine

Answer 20

• MOA: opens K channels
• adjuvant therapy
• SE: dizziness, Sleepiness, urinary retention, urine discoloration
• increases digoxin lvls
• increased metabolism when combined with phenytoin or carbamazepine

Question 21

Phen, phen, carb, carb, top

Answer 21

CYP 3A4 inducers

- phenytoin, phenobarbital, carbamazepine, oxcarbazepine, topiramate

Question 22

2C19

Answer 22

Inhibitor: valproic acid
Inducer: topiramate

Question 23

Calcium channel blockers (4)

Answer 23

• valproic acid
• gabapentin
• pregabalin
• lamotrigine

Question 24

GABA enhancement (3)

Answer 24

Valproic acid
Levetiracetam
Topiramate

Question 25

Glutamate inhibition (2)

Answer 25

Levetiracetam | Topiramate

Question 26

Na channel blockade

Answer 26

- all except gabapentin/pregabalin and levetiracetam

Question 27

Clonazepam

Answer 27

- benzodiazepines | - IV/rectal in status epilepticus

Question 28

Hyponatremia SE

Answer 28

- oxcarbazepine

Question 29

Aplastic anemia SE

Answer 29

Carbamazepine

Question 30

1st line for generalized tonic/clonic (3)

Answer 30

Valproic acid Carbamazepine Phenytoin

Question 31

1st line for Partial seizures (3)

Answer 31

Carbamazepine Lamotrigine Phenytoin

Question 32

1st line Absence seizure (2)

Answer 32

Ethosuximide | Valproic acid

Question 33

1st line drug Myoclonic (1)

Answer 33

Lamotrigine

Question 34

1st line drugs Status epilepticus

Answer 34

IV/rectal lorazepam/diazepam

Question 37

Phenytoin: side effects phenny

Answer 37

- nystagmus - Diplopia and ataxia - gingival hyperplasia - Hirsutism - sedation - osteomalacia - anemia and folate depletion