Pharm - 24: Antiseizure Drugs

Front 1

Which drugs do you use for tonic-clonic seizures?

Back 1

Carbamazepine
Phenytoin
Valproic Acid
Lamotrigine

Front 2

Which drugs do you use for Absence seizures?

Back 2

*Ethosuximide
Valproic Acid
Clonazepam

Front 3

Which drugs do you used for Myoclonic seizures?

Back 3

Valproic acid
Clonazepam
Lamotrigine

Front 4

How are antiseizure drugs generally administered, what is their bioavailability and how are they metabolized?

Back 4

Orally

good biovailability

Hepatic metabolization

Front 5

Which antiseizures INDUCE hepatic P450 enzymes?

Back 5

Carbemazepine
Phenytoin

Front 6

Which antiseizures INHIBIT hepatic P450 enzymes?

Back 6

Valproic Acid

Front 7

What kind of metabolism doe sphenytoin have?

Back 7

Non-linear, Zero-order at high doses.

Front 8

What drugs enhance Phenytoin's metabolism?

Back 8

Phenobarbitol
Rifampin

Front 9

Whhat drugs inhibit phenytoin's metabolism?

Back 9

Cimetidine
Isoniazid

Front 10

How does phenytoin affect the metabolism of other antiseizure drugs?

Back 10

It INDUCES P450, so decreases the effects of antiseizure drugs:
carbemazepine
clonazepam
lamotrigine

Front 11

This water-soluble drug is the prodrug of phenytoin and is administered parenterally

Back 11

Fosphenytoin

Front 12

How does carbemazepine affect P450

Back 12

INDUCES P450 liver enzymes to increase the metabolism of itself.

Increases the clearance of other drugs - clonazepam, lamotrigine, valproic acid

Front 13

Which drug related to carbemazepine is less likely to be involved in drug interaction

Back 13

Oxcarbazepine

Front 14

How does Valproic acid affect P450

Back 14

INHIBITS P450

Front 15

How does Valproic acid affect Phenytoin

Back 15

it competes for phenytoin plasma protein binding sites

Front 16

Which antiseizures are metabolized by the KIDNEY only?

Back 16

Gabapentin
Levetiracetam
Vigabatrin

eliminated unchanged

Front 17

Which antiseizures are metabolized by both Liver AND Kidney

Back 17

Felbamate
Topiramate

Front 18

How is Lamotrigine metabolized?

Back 18

Hepatic glururonidation

Front 19

What are the main mechanisms of action involved in antiseizure drugs

Back 19

1.) Block Inactivated Na+ channels - prolong AP
2.) Facilitate GABA
3.) Block T-type Ca channels
4.) Enhance K channels -> hyperpolarization, and inhibit glutamate receptors

Front 20

Which drugs block inactivated Na channels?

Back 20

Phenytoin
Carbamazepine
Lamotrigine

Front 21

Describe the MOA of Benzodiazepines

Back 21

increase the FREQUENCY of Chloride channel opening

Facilitate effects of GABA

Front 22

Describe the MOA of Barbiturates

Back 22

increase the DURATION of Chloride ion channels

Facilitate effects of GABA but bind to a different receptor site on channel

Front 23

Which enzyme terminates the action of GABA?

Back 23

GABA Aminotransferase
(GABA-T)

Front 24

Which drugs irreversibly inactivates GABA-T

Back 24

Vigabatrin - at therapeutic doses

Valproic acid - at high doses

Front 25

Which drug inhibits a GABA-transporter (GAT-1) in neurons and glia, prolonging the action of the neurotransmitter?

Back 25

Tiagabin

Front 26

Which drug is a strugtural analog of GABA but does not activate GABA receptors directly

Back 26

Gabapentin

Front 27

What other drugs facilitate GABA

Back 27

Felbamate
Topiramate
Valproic Acid

Front 28

Which drug inhibits T-type Ca2+ channels? and Where in the brain does it do so?

Back 28

Ethosuximide

In the THALAMUS - as a pacemaker to generate rhythmic cortical discharge

Valproic acid does too

Front 29

In addition to inhibiting Calcium channels, this drug hyperpolarizes the neuron by enhancing K+ channels

Back 29

Valproic Acid

Front 30

In addition to inhibiting Na+ channels and GABA-Cl channels, this drug is also an antagonist of Glutamate receptors

Back 30

Phenobarbitol

Front 31

Which type of Glutamate receptors does Felbamate block?

Back 31

NMDA receptors

Front 32

MOA of Topiramate

Back 32

blocks Na+ channels, potentiates GABA effects, and may block Glutamate receptors.

Front 33

DOCs for Grand Mal Seizures

(Generalized Tonic-Clonic)

Back 33

Valproic Acid
or
Carbemazepine
or
Phenytoin

Front 34

DOCs for Partial Seizsures

Back 34

Carbemazepine
or
Lamotrigine
or
Phenytoin

Front 35

DOCs for Absence Seizures

Why?

Back 35

Ethosuximide
or
Valproic Acid

Less sedation

Front 36

For absence seizures, what would use if they were UNcomplicated? what about Complicated?

Back 36

Ethosuximide for uncomplicated, if they can tolerate the GI SE's

Valproic acid for absence w/ concomitant Grand mal or myoclonic.

Front 37

Disadvantages of using clonazepam

Back 37

sedation and tolerance

Front 38

DOCs for Myoclonic & Atypical Absence syndromes

Back 38

Valproic acid

Lamotrigine as adjunctive, but sometimes used alone too

Front 39

Why is Felbamate not used as commonly?

Back 39

Hematoxic and Hepatotoxic potential

Front 40

What drugs are usu used for Status Epilepticus?

Back 40

i.v. Diazepam or Lorazepam

Front 41

Whats used for prolonged status epilepticus therapy

Back 41

i.v. phenytoin

Front 42

SE of Phytoin?

Back 42

Cardiotoxicity b/c its solvent is propylene glycol

Front 43

What is a safer alternatuve to pheyntoin, why

Back 43

Fosphenytoin - water soluble

Front 44

Drug used for status epilepticus in chldren

Back 44

Phenobarbital

Front 45

Last resort if no other drugs work for status epilepticus

Back 45

general anesthesia

Front 46

What psychological use do antiseizure drugs have?

Back 46

Bipolaraffective Disorders

Front 47

Which antiseizures are used for biopolar disorder?

Back 47

Valproic acid
Carbemazepine
Lamotrigine

Front 48

Which antiseizure is first line for mania

Back 48

Valproic acid

Front 49

Which drug is DOC for Trigeminal neuralgia?

Back 49

Carbemazepine

Front 50

What pain is Gabapentin used for?

Back 50

pain with neuropathic origin

like from post herpetic neuralgia

Front 51

Teratogenicity of phenytoin

Back 51

fetal hydantoin syndrome

Anterior chord doesn't close

Front 52

Teratogenicity of carbamazepine

Back 52

BOTH
craniofacial abnorm's - Cleft lip, or palate
&
Spina bifida

Anterior and posterior chords don't close

Front 53

Teratogenicity of valproic acid

Back 53

NTD's - spina bifida

Posterior chord doesn't close

Front 54

What occurs with antiseizure overdose

Back 54

CNS depression (even at normal doese)

Respiratory Depression

Front 55

What do you use for Benzo overdose?

Back 55

Flumazenil

Front 56

Life threatening toxicity of valproic acid, esp in which populations?

Back 56

fatal hepatotoxicity

babies less than 2 y.o. & ppl already taking many anticonvulsants

Front 57

SE of Lamotrigine

Back 57

Stephen-Johnsons Syndrom
or toxic epiderma necrolysis

higher risk if child or taking valproic acid

Front 58

B/c of its severe SE's. Felbamate is limited to being used for

Back 58

refractory seizure states

Front 59

Withdrawal from which type of drugs is easiest?

Back 59

anti absence drugs easier to withdraw than partial or generalized tonic-clonic seizure states.

Front 60

* Most frequent route of metabolism of antiseizures

Back 60

* Hepatic enzymes

Front 61

*

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*

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*

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*

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*

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Front 70

*

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*

Front 71

* Mechanisms of action of Phenytoin, Carbemazepine, Lamotrigine

Back 71

* Inactive Na+ channel blockade

Front 72

* MOA of benzodiazepines and barbiturates

Back 72

* GABA-related targets

Benzo's increase FREQUENCY
Barbiturates increase DURATION

Front 73

* MOA of Ethosuximide

Back 73

* Calcium Channels

Front 74

* MOA of Valproic Acid at high doses

Back 74

* Affect Calcium, Potassium, and Sodium channels

Front 75

* DOC's for Generalized Tonic-Clonic and partial seizures

Back 75

* Valproic acid and Phenytoin

Front 76

* DOC for Febrile seizures

Back 76

* Phenobarbital

Front 77

* DOC's for Absence seizures

Back 77

* Ethosuximide and Valproic Acid

Front 78

* DOC for Myoclonic Seizures

Back 78

* Valproic Acid

Front 79

* DOC for Status Epilepticus

Back 79

* i.v. Diazepam for Short-term (Acute)

Phenytoin for prolonged therapy

Front 80

* Drugs that can be used fo rinfantile spasms

Back 80

* Corticosteroids

Front 81

* Anti-seizure drugs used also for Bipolar Affective Disorder

Back 81

* Valproic acid, carbamazepine, phenytoin, Gabapentin

Front 82

* Anti-seizure drugs used also for Trigmeinal Neuralgia

Back 82

* Carbamazepine

Front 83

* Anti-seizure drug used also for pain of neuropathic orgin

Back 83

* Gabapentin

Front 84

* Anti-seizure drug that exhibits non-linear metabolism, highly protein bound, causes fetal hydrantoin syndrome and stimulates hepatic metabolism

Back 84

* Phenytoin

Front 85

* SE of phenytoin

Back 85

* Gyngival hyperplasia
Hirsutism
Nystagmus
Diploplia
Ataxia

Front 86

* ANti-seizure drug that induces form'n of liver drug-metabolism enzymes, is a teratogen, and can cause craniofacial abnormalities and spina bifida

Back 86

* Carbamazepine

Front 87

* Agent that inhibits hepatic metabolism, is hepatotoxic and a teratogen that causes NTD's and GI distress

Back 87

* Valproic Acid

Front 88

* Lab value required to be monitored of pts on valproic acid

Back 88

* Serum ammonia and LFT's

Front 89

* SE of Lamotrigine

Back 89

* SJS

Front 90

* SE of Felbamate

Back 90

* Aplstic anemia & acute hepatic failure

Front 91

* Anti-seizure drug that can also be used for migraines

Back 91

* Valproic acid

Front 92

* Carbemazepine may also cause

Back 92

* Agranulocytosis

Front 93

* Anti-seizure drugs used as "alternative drugs" for mood stabilization

Back 93

* Carbamazepine, lamotrigine, gabapentin and valproic acid