Drug treatment of epilepsy

Question 1

What symptoms are produced when the 1. motor cortex, 2. hypothalamus, 3. reticular formation are affected

Answer 1

1. Convulsions
2. Peripheral autonomic effects
3. Loss of consciousness

Question 2

Explain the two major forms of epilepsy and there subsets.

Answer 2

1, Partial seizures - Simple (consciusness not affected (motor or sensory)). Complex (consciusness affected)
2. Generalised seizures - discharge involves both hemispheres and reticular system -> consciousness affected (i) Absence seizures (ii) Tonic-clonic seizures

Question 3

Which type of seizure is most common in children accompanied with staring spells?

Answer 3

Absence / petit mal seizures

Question 4

Name the 4 main mechanism of AEDs

Answer 4

1. Use-dependent Na+ channel block
2. Ca2+ channel inhibition
3. Increase GABA-mediated neural inhibition
4. Inhibit glutaminergic transmission

Question 5

List some other AED approaches

Answer 5

Carbonic Anhydrase inhibitors
Hormones
Cannabidiol (CBD)
Ketogenic diet

Question 6

Name the Na+ channel blockers.

Answer 6

1. Carbamazepine
2. Oxcarbazepine
3. Phenytoin
4. Lamotrigine
5. Zonisamide

Question 7

Explain the metabolism of carbamazepine and what enzyme metabolises this drug?

Answer 7

Epoxidation to CBZ-10,11-epoxide -> Hydrolysis to CBZ-10,11-trans-dihydrodiol
Strong inducer of P450 enyzmes

Question 8

Which group of drugs does oxcarbazepine interact with?

Answer 8

Interacts with oral contraceptives
Do not interacct with warfarin, cimetidine and erythromycin

Question 9

Which drugs also act as GABA receptor agonists and have been used for neuropathic pain and schizophrenia?

Answer 9

Carbamazepine + oxcarbamazepine

Question 10

Which enzyme metabolises Phenytoin?

Answer 10

Metabolised by and induces CYP450

Question 11

Which enzyme metabolises zonisamide?

Answer 11

metabolised by cyp450, then glucuronidation

Question 12

Which type of Ca channel does ethosuximide inhibit?

Answer 12

T-type Ca channel

Question 13

Name the drugs which inhibit Ca channels

Answer 13

Gabapentin, ethosuximide

Question 14

Name the drugs which increases GABA in the brain?

Answer 14

Valproate, vigabatrin

Question 15

Name the drugs which are involved in GABA reuptake inhibition

Answer 15

Tiagabine

Question 16

Which transporter does tiagabine inhibit?

Answer 16

Irreverisbly inhibits GABA-transporter-1 (GAT-1) in neurons and glia. Penetrates BBB.

Question 17

Which drugs increase GABA receptor response?

Answer 17

Phenobarbital, benzodiazepines

Question 18

Name glutamate receptor antagonists?

Answer 18

Felbamate, topiramate

Question 19

Which receptor does Felbamate inhibit?

Answer 19

NMDA glutmate receptor antagonist

Question 20

Which receptor does Topiramate inhibit?

Answer 20

AMPA glutamate receptor antagonist

Question 21

Name a carbonic anydrase inhibitor

Answer 21

Acetazolamide

Question 22

Is progesterone a proconvulsant or an anticonvulsant?

Answer 22

Anticonvulsant

Question 23

Which condition is Cannabidiol approved for?

Answer 23

Dravett’s syndrome