Epilepsy

Question 1

How have most drugs for the CNS been discovered?

Answer 1

Serendipity

Question 2

What is Carbamazepine and what does it do?

Answer 2

Anti-seizure drug
DRUG OF CHOICE
Blocks Sodium Channel by forcing it into the inactivated state
“use-dependent block”
INDUCES MICROSOMES
meaning it increases metabolism of itself and other drugs

Question 3

What is Phenytoin and what does it do?

Answer 3

Anti-seizure drug
Blocks Sodium Channel by forcing it into the inactivated state
“use-dependent block”
A few MAJOR pharmacokinetic drawbacks
Zero order kinetics, No two patients are the same
Binds to plasma proteins (Interactions with eg aspirin)
Gingival hyperplasia and hirsutism

Question 4

What is ehosuxamide and what does it do?

Answer 4

Anti-seizure drug
Only alleviates absence
Inhibits a CERTAIN KIND of Calcium channel found in reciprocal connections between cerebral cortex and thalamus

Question 5

What is phenobarbital and what does it do?

Answer 5

Anti-seizure drug
(Less effective, barbiturate, more for historical interest)
Hepatic microsomes
O/D
Sedation
Teratogen

Question 6

What is diazipam and what does it do?

Answer 6

Anti-seizure drug
Drug of choice in “status epilepticus” (secret fifth seizure)
Don’t use chronically
Doesn’t inhibit calcium channel, but still treats absence (somehow)

Question 7

What is Valproate and what does it do?

Answer 7

Anti-seizure drug
Blocks Sodium Channel by forcing it into the inactivated state
AND
Inhibits GABA-T (i.e. inhibits breakdown of GABA)
ALSO inhibits Thalamic Ca2 channels
“use-dependent block”

Question 8

What are the two basic kinds of seizure? What is the difference?

Answer 8

Focal onset and Generalized onset
Focal onset: 
- focus in one hemisphere
- Conscious
- May become generalized

Generalized:

• Both hemispheres
• Unconscious
• Cortex

Question 9

What are the two types of Focal epilepsy?

Answer 9

Focal Aware

Focal Impaired Awareness

Question 10

What are the symptoms of a focal aware seizure?

Answer 10

No generalized symptoms, depend on where focus is

Question 11

What are the symptoms of a focal aware seizure?

Answer 11

No generalized symptoms, depend on where focus is

Question 12

What are the symptoms of Impaired awareness seizures?

Answer 12

Usually affects temporal lobe
Consciousness is lost or impaired
Preceded by aura
Simpal "automatisms" or complex "psychomotor attack"
Most common subtype of epilepsy

eg. following woman in park, doing a pirouette, smacking lips, etc

Question 13

What are the two types of Generalized seizure?

Answer 13

Tonic-Clonic

Abscence

Question 14

What are the symptoms of Tonic-Clonic Seizure?

Answer 14

“Grand mal”

Tonic phase for 30 seconds, all muscles contracted

Clonic phase for 1-3 minutes, back and forth contraction

Post-ictal phase, recovery (most patients sleep)

Question 15

What are symptoms of absence seizure?

Answer 15

“petit mal” loss of consciousness, looks like internet got cut

Question 16

When is consciousness lost for the 4 different types of seizure?

Answer 16

Aware: never
Awareness impaired: never but impaired
Tonic-clonic: Immediately lost
Absence: immediately lost

Question 17

When is consciousness lost for the 4 different types of seizure?

Answer 17

Aware: never
Awareness impaired: never but impaired
Tonic-clonic: Immediately lost
Absence: immediately lost

Question 18

What is characteristic about the EEG of an absence seizure?

Answer 18

3 Hz “spike and wave”

Question 19

True/False? Focal Aware seizures are visible on EEGs on one side only

Answer 19

True

Question 20

What does a scalp EEG measure?

Answer 20

Pyramidal cell activity

If cortical cells fire enough, activity passes through cells

Question 21

True/False? Most types of epilepsy are inherited

Answer 21

False, only some

Question 22

True/False? Most types of epilepsy are inherited

Answer 22

False, only some

Question 23

What is the main symptom of epileptic brains (what has been observed in the past 20 years of research)

Answer 23

Chennelopathies (acquired or inherited)

Mutations in voltage gated Na and K channels

Question 24

True/False? Bromides cure epilepsy

Answer 24

False. They treat epilepsy

There is no cure for epilepsy

Question 25

True/False? Bromides cure epilepsy

Answer 25

False. They treat epilepsy

There is no cure for epilepsy

Question 26

Describe the GABA synapse

Answer 26

Glutamate is converted to GABA at the presynapse
GABA is released 
Acts on GABA-A receptors
Reuptaken by GABA uptake carriers
Broken down by GABA-T(ransaminase)

Question 27

True/False? Drugs for focal seizures also work for tonic-clonic seizures

Answer 27

True (basically)

Question 28

Name the only anti-seizure drug with that doesn’t inhibit focal or tonic/clonic seizures

Answer 28

Ethosuxamide

Question 29

Can increased GABA explain Valproate and Ethosuxamide (and BZs) effect on absence seizures?

Answer 29

No

Question 30

Can increased GABA explain Valproate and Ethosuxamide (and BZs) effect on absence seizures?

Answer 30

No

Question 31

How are Benzodiazepines like Diazepam used for anti seizure?

Answer 31

Drug of choice in “status epilepticus” (secret fifth seizure)
Don’t use chronically
Doesn’t inhibit calcium channel, but still treats absence (somehow)

Question 32

What does vigabatrin do?

Answer 32

Anti-seizure drug
Inhibits GABA-T
viGABATrin

Question 33

What kind of channel is the AMPA glutamatergic receptor?

Answer 33

Glutamate ligand-gated ion channel

Binds glutamate and lets Na in

Question 34

What is the side effect of drugs that treat siezures via NMDA receptor block?

Answer 34

Ataxia

Question 35

Should you discontinue Anti-seizure drugs during pregnancy?

Answer 35

you SHOULD, but only if possible

If not possible, try monotherapy at minimal effective dose