Antiseizure drugs

Question 1

What is a seizure?

Answer 1

transient disturbance of cerebral function due to an abnormal paroxysmal neuronal discharge in the brain.

Question 2

Dif. between epilepsy and seizures?

Answer 2

duration of sxs

Epilepsy: chronic, recurrent

Seizures: finite, resolves

Question 3

What are the 2 classifications of epileptic seizures?

Answer 3

focal seizures

generalized seizures

Question 4

What is a focal onset seizure?

Answer 4

formerly partial seizure

start in an area or network on one side of the brain

Question 5

What is a generalized onset seizure?

Answer 5

affects both sides of the brain or large networks of cells on both sides from the beginning

doesn’t need to involve entire brain

Question 6

What is an unknown onset seizure?

Answer 6

if the beginning of seizure is not clear/observed

Question 7

Generalized absence seizure

Answer 7

consciousness impaired briefly

almost always begin in childhood, freq. cease by 20 y/o

Question 8

What are the types of focal seizures?

Answer 8

focal aware, focal impaired awareness, focal to bilateral tonic clonic

Question 9

define focal aware seizure

Answer 9

no change in person’s awareness

Question 10

define focal impaired awareness

Answer 10

awareness is impaired during a focal seizure

Question 11

define focal to bilateral tonic clonic seizure

Answer 11

focal seizure may start in one part of the brain with the person aware or with impaired awareness
spreads to involve both sides of the brain and person unaware during the seizure

Question 12

What is preferred in tx of seizures?

Answer 12

monotherapy

Question 13

When should ASDs be initiated?

Answer 13

in pts who have had two or more unprovoked seizures

Question 14

What are some drugs that lower seizure threshold?

Answer 14

theophylline, alcohol, high dose phenothiazines, antidepressants, street drugs

Question 15

When to consider stopping ASDs?

Answer 15

seizure free 2-4 yrs

complete seizure control within 1 yr

onset of seizure btwn 2-35 yrs old

+ normal neuro exam and EEG

Question 16

What are the 3 proposed MOA of seizure drug therapy?

Answer 16

1. enhancement of GABAergic (inhibitory) transmission
2. Decrease excitatory (usually glutamatergic) transmission
3. Modification of ionic conductance

Question 17

Ethosuximide only works for..

Answer 17

Absence seizures

Question 18

What drugs can be used in the tx of general absence seizures?

Answer 18

Ethosuximide**

Lamotrigine

Valporic acid

Question 19

What drug alternatives can be used for refractory absence?

Answer 19

Clonazepam

Topriamate

Question 20

MOA of Ethosuximide?

Answer 20

Decreases VG-Ca2+ currents decreases glutamate

Question 21

ADEs of ethosuximide?

Answer 21

HA, blood dyscrasias, GI distress, drowsiness, rash

chronic: behavior changes

Question 22

Lamotrigine MOA?

Answer 22

Blocks Na+ and Ca2+ channels, decreases glutamate

Question 23

What can Lamotrigine be used for?

Answer 23

Generalized tonic-clonic

Focal aware/impaired

Focal or Generalized
Myoclonic

Generalized Absence

Question 24

Box warning for Lamotrigine?

Answer 24

serious skin rash- start low and go slow, diplopia

Other ADEs: HAs, dizziness

Question 25

Valporic acid MOA?

Answer 25

Alters synthesis and degradation of GABA

Question 26

What can valporic acid be used for?

Answer 26

Generalized tonic-clonic Focal aware/impaired Focal or Generalized Myoclonic Generalized Absence

Question 27

Black box warning for Valporic Acid?

Answer 27

hepatotoxicity, teratogenic, pancreatitis, alopecia other sxs: alopecia, nausea, weight gain Dont give to women of child bearing age

Question 28

What meds are FDA approved for tonic clonic seizures?

Answer 28

Topiramate- US guidelines Lamotrigine Levatriacetam Perampanel

Question 29

What meds are ineffective in absence seizures?

Answer 29

Phenytoin Phenobarbitol

Question 30

What meds can aggravate absence seizures & therefore should be avoided?

Answer 30

carbamazepine vigabatrin gagapentin tiagabin

Question 31

ADE of clonazepam?

Answer 31

Sedation

Question 32

ADEs of topiramate?

Answer 32

Cognitive slowing, confusion

Question 33

Carbamazepine box warning?

Answer 33

Serious derm rxns HLA-B*1502 allele (TEN, SJS) in Asians Aplastic anemia, agranulocytosis Ataxia, diplopia, hyponatremia, MBD (Vit D & Ca)

Question 34

What drug can increase PR interval?

Answer 34

Lacosamide

Question 35

What med induces its own metabolism?

Answer 35

Carbamazepine

Question 36

ADEs of phenytoin?

Answer 36

``` Ataxia nystagmus gingival hyperplasia hirsutism neuropathy folate deficiency, MBD ```

Question 37

Phenytoin box warning?

Answer 37

Cardio risk associated w/ rapid infusion

Question 38

ADEs of phenybarbitol?

Answer 38

Sedation Intellectual blunting MBD Behavior changes

Question 39

ADEs of both gabapentin & pregablin (Lyrica)?

Answer 39

Ataxia Somnolence Wt gain

Question 40

Vigabatrin box warning?

Answer 40

Permanent vision loss

Question 41

Perampanel box warning?

Answer 41

Serious psychiatric & behavioral rxns

Question 42

ADEs of tiagabine?

Answer 42

Concentration & attention difficulties Behavioral disturbances Increased appetite

Question 43

ADEs of levetiracetam?

Answer 43

Behavioral problems HA

Question 44

ADEs of zonisamide?

Answer 44

Cognitive slowing Paresthesia Rash-sulfa based drugs Kidney stones Oligohydrosis

Question 45

What drugs interact w/ phenytoin?

Answer 45

Fluoxetine Fluconazole Digoxin Isoniazid OCPs

Question 46

What drugs interact w/ phenobarbitol?

Answer 46

Nifedipine Theophylline Verapamil

Question 47

What drugs interact w/ rifampin?

Answer 47

valporate & euthosuximide

Question 48

What drugs interact w/ carbamazepine?

Answer 48

Fluoxetine Verapamil Macrolides Isoniazid

Question 49

What drug interacts w/ lamotrigine?

Answer 49

Sertraline

Question 50

What drugs interact w/ topiramate?

Answer 50

OCPs Lithium?