Epileptic discharges

Question 1

What can epilepsy be described as?

Answer 1

as uncontrolled excessive synchronisation of CNS

activity.

Question 2

What is status epilepticus?

Answer 2

A single seizure lasting more than 5 mins or two or more seizures within a five minute period without the person returning to normal between them

Question 3

What is used to treat status epilepticus?

Answer 3

Benzodiazepine

Phenytoin

Question 4

MoA of benzodiazepine

Answer 4

GABA(A) agonist

Increased chloride influx causes hyperpolarisation

Question 5

MoA of phenytoin

Answer 5

Voltage-dependent block of voltage-gated Na channels

Blocks sustained high firing

Question 6

What is used for the management of chronic epilepsy?

Answer 6

Valproate

Carbamazepine Lamorigine

Question 7

MoA valproate

Answer 7

Blockade of voltage-gated Na channels

Ca channel

(?)increased brain levels of GABA (possibly by inhibiting the GABA degradative enzymes)

Question 8

MoA carbamezapine

Answer 8

Na+ channel blocker
Voltage-gated Na channels in inactive configuration
evidence that it is also a serotonin releasing agent

Question 9

MoA lamorigine

Answer 9

Sodium channel blocker → stabilised membranes

Also thought to block Ca channels and weakly inhibit 5-HT3 receptor → inhibit release of glutamate (mood stabilising)