AEDs

Question 1

Treatment of seizures typically tries to affect what 2 transmitters?

Answer 1

decreased effectiveness of GLU

increase effectiveness of GABA

Question 2

What is the mechanism of action for carbamazepine?

Answer 2

It stabilizes the “inactivated” state of VG Na+ channels to decrease repetitive firing

Question 3

What is the main therpauetic use of carbamazepine?

Answer 3

grand mal seizures

Question 4

What are some side effects of carbamazepine

Answer 4

1. diplopia
2. gait instability
3. inducer of cyp450

Question 5

What is the mechanism of action for ethosuximide?

Answer 5

It blocks the T-type voltage gated calcium channels in postynaptic thalamic neurons

Question 6

What is the main therapeutic use of ethosuximide?

Answer 6

absence seizures

Question 7

What are the side effects of ethosuximide?

Answer 7

GI distress
fatigue
headache
dizziness

Question 8

What is the mechanism of action for levetiracetam?

Answer 8

It affects synaptic vesicle protein (SV2A), resulting in decreased GLU release, but increased GABA release!

Question 9

What is the main therapeutic use of leviteracitam

Answer 9

partial seizures

Question 10

What is the kinetic order for levitiracetam?

Answer 10

zero order

Question 11

What are some side effects of levetiracetam?

Answer 11

headache
somnolence
dizziness
asthenia

Question 12

What is the mechanism of action for topiramate?

Answer 12

increased inactivation of VG Na+ channels

- blocks presynaptic type N and typ P/Q VG Ca2+ channels

Question 13

What is the main therapeutic use for topiramate?

Answer 13

partial and generalized tonic-clonic seizures.

great for monotherapy

Question 14

What are some side effects of topiramate?

Answer 14

parasthesias, anorexia, idiosyncratic glaucoma, stones, cognitive slowing

Question 15

What is the mechanism of action for phenytoin?

Answer 15

It prolongs the inactivation of VG Na+ channels, preventing rapid firing of action potentials

Question 16

What is the main therapeutic use for phenytoin?

Answer 16

Generalized tonic clonic seizures

status epilepticus

Question 17

What is critical to know about the pharmacokinetics of phenytoin?

Answer 17

It has zero order kinetics, so when the metabolizing enzymes are saturated, even small dose changes will cause large changes in drug concentration, increasing toxicity without added benefit

so if phenytoin isn’t working for someone, just switch them to a new drug - don’t increase dose

Question 18

What are some side effects of phenytoin?

Answer 18

nystagmus, diplopia
ataxia
sedation
induction of cyp450 and protein binding leads to drug interactions

Question 19

What is the mechanism of action for tiagabine?

Answer 19

Inhibits reuptake of GABA via GAT1, thus increasing the amount of GABA available to postsynaptic neurons

Question 20

What is the therapeutic use for tiagabine?

Answer 20

partial seizures

Question 21

What are the size effects of tiagabine?

Answer 21

nervousness
dizziness
depression
seizures

Question 22

What is the mechanism of action for valproic acid?

Answer 22

blocks VG Na+ channels, blocks NMDA receptors, decreases GABA reuptake

Question 23

What is the main therapeutic use for valproic acid?

Answer 23

absence seizures - especially when combined with some generalized tonic/clonic

Question 24

What are the main side effects of valproic acid?

Answer 24

GI upset
Drug interactions with other anticonvulsants because it decreases liver metabolism
Hepatotoxicity - can be fatal
Teratogenic (inhibits HDAC)

Question 25

What is the mechanism of action for gabapentin?

Answer 25

It’s a GABA analog, but blocks VG Ca2+ channels

Question 26

What barbiturate is used to treat seizure?

Answer 26

phenobarbital

Question 27

What benzodiazepines are used to treat seizures?

Answer 27

diazepam

lorazepam