Drug treatment of epilepsy Flashcards
What symptoms are produced when the 1. motor cortex, 2. hypothalamus, 3. reticular formation are affected
- Convulsions
- Peripheral autonomic effects
- Loss of consciousness
Explain the two major forms of epilepsy and there subsets.
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
Which type of seizure is most common in children accompanied with staring spells?
Absence / petit mal seizures
Name the 4 main mechanism of AEDs
- Use-dependent Na+ channel block
- Ca2+ channel inhibition
- Increase GABA-mediated neural inhibition
- Inhibit glutaminergic transmission
List some other AED approaches
Carbonic Anhydrase inhibitors
Hormones
Cannabidiol (CBD)
Ketogenic diet
Name the Na+ channel blockers.
- Carbamazepine
- Oxcarbazepine
- Phenytoin
- Lamotrigine
- Zonisamide
Explain the metabolism of carbamazepine and what enzyme metabolises this drug?
Epoxidation to CBZ-10,11-epoxide -> Hydrolysis to CBZ-10,11-trans-dihydrodiol
Strong inducer of P450 enyzmes
Which group of drugs does oxcarbazepine interact with?
Interacts with oral contraceptives
Do not interacct with warfarin, cimetidine and erythromycin
Which drugs also act as GABA receptor agonists and have been used for neuropathic pain and schizophrenia?
Carbamazepine + oxcarbamazepine
Which enzyme metabolises Phenytoin?
Metabolised by and induces CYP450
Which enzyme metabolises zonisamide?
metabolised by cyp450, then glucuronidation
Which type of Ca channel does ethosuximide inhibit?
T-type Ca channel
Name the drugs which inhibit Ca channels
Gabapentin, ethosuximide
Name the drugs which increases GABA in the brain?
Valproate, vigabatrin
Name the drugs which are involved in GABA reuptake inhibition
Tiagabine
Which transporter does tiagabine inhibit?
Irreverisbly inhibits GABA-transporter-1 (GAT-1) in neurons and glia. Penetrates BBB.
Which drugs increase GABA receptor response?
Phenobarbital, benzodiazepines
Name glutamate receptor antagonists?
Felbamate, topiramate
Which receptor does Felbamate inhibit?
NMDA glutmate receptor antagonist
Which receptor does Topiramate inhibit?
AMPA glutamate receptor antagonist
Name a carbonic anydrase inhibitor
Acetazolamide
Is progesterone a proconvulsant or an anticonvulsant?
Anticonvulsant
Which condition is Cannabidiol approved for?
Dravett’s syndrome
