Antiepileptic Drugs

Question 1

Define primary (aka idopathic epilepsy)

Answer 1

Epilepsy without an identifiable cause

Question 2

Define Secondary (aka symptomatic) epilepsy

Answer 2

Epilepsy that has a distinct cause such as trauma, infection, cerebrovascular disorder, etc.

Question 3

What is the difference between a “Generalized Onset Seizure” and a “Partial Onset Seizure”?

Answer 3

1) Generalized Onset Seizure - Characterized by neuronal activity that originates simultaneously in the gray matter of both hemispheres.
2) Partial Onset Seizure - Originates in a localized or focal region (e.g., one lobe) of the brain.

Question 4

What 6 things classify a Simple Partial Seizure?

Answer 4

1) No impaired consciousness
2) Motor symptoms
3) Hallucinations of sight, hearing, or taste
4) Tingling
5) ANS response
6) Personality changes

Question 5

What 5 things classify a Complex Partial Seizure?

Answer 5

1) Impaired consciousness
2) Memory impairment
3) Purposeless behavior
4) Aura
5) Tonic, clonic, or tonic-clonic seizures

Question 6

What 4 things classify a Generalized Seizure?

Answer 6

1) Both cerebral hemispheres involved
2) Tonic, clonic, myoclonic, atonic, or tonic-clonic seizures and infantile spasms possible
3) Brief loss of consciousness for a few seconds with no confusion
4) Head drop or falling-down symptoms

Question 7

What is believed to be the mechanism of action of antiepileptic drugs?

Answer 7

Antiepileptic drugs are believed to alter the movement of sodium, potassium, calcium and magnesium ions, which results in more stabilized and less excitable cell membranes.

Question 8

What are the 3 pharmacologic effects of antiepileptic drugs?

Answer 8

1) Increase threshold activity which reduces the nerve’s response to incoming signal.
2) Limit the spread of a seizure from its origin
3) Decrease the speed of a nerve impulse conduction

Question 9

What are the 5 class of drugs used to manage seizure disorders?

Answer 9

1) Barbiturates
2) Benzodiazepines
3) Hydantoins
4) Iminostilbenes
5) Miscellaneous Drugs

Question 10

Why should carbamazepine not be given with grapefruit juice?

Answer 10

Coadministration leads to increased toxicity of the antiepileptic drug.

Question 11

What are the 2 types of Hydantoin drugs?

Answer 11

1) Phenytoin

2) Fosphenytoin

Question 12

What are the 7 adverse effects of Hydantoins?

Answer 12

1) Nystagmus
2) Ataxia
3) Dizziness
4) Drowsiness
5) Rash
6) Gingival Hyperplasia
7) Blood dyscrasias

Question 13

Name 5 advantages of Phenytoin that make it the number one prescribed antiepileptic drug.

Answer 13

1) Well tolerated
2) Highly effective
3) Cheap
4) Can be given via PO or IV
5) Long-Half Life - means less daily dosing and increased PT adherence to drug therapy.

Question 14

Exaggerated Phenytoin effect can be seen in PTs with what condition? What can be done?

Answer 14

Patients with very low serum albumin. In these PTs it may be necessary to maintain Phenytoin levels well below 20 mcg/mL

Question 15

What is the therapeutic drug range of Phenytoin?

Answer 15

10 to 20 mcg/mL

Question 16

What is the advantage of Fosphenytoin over Phenytoin?

Answer 16

Fosphenytoin is a prodrug of Phenytoin that can be given via IM or IV without causing the burning sensation.

Question 17

What are the 3 contraindications of Carbazepine (an Imiostilbenes)?

Answer 17

1) Myoclonic seizures
2) Absence seizures
3) Bone marrow depression

Question 18

What is Autoinduction and which drug is associated with it?

Answer 18

Carbamazepines are associated with autoinduction, a process in which, overtime, a drug stimulates the production of enzymes that enhance its own metabolism, which leads to lower than expected drug concentrations.

Question 19

What are the 2 drugs in the Iminostilbene class of atiepileptic drugs?

Answer 19

1) Carbamazepine

2) Oxcarbazepine

Question 20

What are the 3 adverse effects of the Iminostilbene class of antiepileptic drugs?

Answer 20

1) Behavioral changes
2) Unusual eye movements
3) Mental or mood changes

Question 21

What are the 7 miscellaneous drugs used as antiepileptics?

Answer 21

1) Gabapentin 2) Pregabalin
3) Lamotrigine 4) Levetiracetam
5) Tiagabine 6) Topiramate
7) Zonisamide

Question 22

Which Miscellaneous antiepileptic drug can cause the serious adverse effect known as “Stevens-Johnson Syndrome”?

Answer 22

Lamotrigine

Question 23

Which miscellaneous antiepileptic drug can cause paradoxical seizures when used for “off label” indications?

Answer 23

Tiagabine

Question 24

Which miscellaneous antiepileptic drug is indicated for postherpetic neuralgia neuropathic pain.

Answer 24

Gabapentin

Question 25

Which miscellaneous antiepileptic drug binds to alpha2-delta receptor sites and affect calcium channels in the CNS tissues?

Answer 25

Pregabalin

Question 26

Which miscellaneous antiepileptic drug is available in both oral and injectable forms?

Answer 26

Levetiracetam

Question 27

Which miscellaneous antiepileptic drug is structurally related to fructose, is indicated for drop-attack and Lennox-Gastaut syndrome and has angle-closure glaucoma as an adverse effect?

Answer 27

Topiramate

Question 28

Which miscellaneous antiepileptic drug is indicated for myoclonic seizures?

Answer 28

Zonisamide

Question 29

What 5 things should you teach your patient about Antiepileptic Drugs?

Answer 29

1) Avoid tasks requiring alertness
2) Avoid alcohol and smoking
3) Do not abruptly discontinue the drug
4) Avoid stimulants such as caffeine
5) Avoid sunlight or tanning beds