Anti-seizure pharmacology

Question 1

Carbamazapine

Answer 1

MOA: inhibition of voltage-dependent sodium channels, thus decreasing the upstroke of the action potential
Adverse Effects: teratogenic (as with all anti-seizure drugs), drug-drug interactions via CYP450 induction
Uses: tonic clonic and partial seizures

Question 2

Lamotrigine

Answer 2

MOA: slows the depolarization of the action potential by inhibiting VDNaC
Adverse effects: ataxia… less drug-drug interactions because lamotrigine is metabolized by phase II glucaronidation
Uses: partial and tonic clonic

Question 3

Phenytoin

Answer 3

MOA: anti-VDNaC
Adverse effects: dose-dependent toxicities, very teratogenic, gingival hyperplasia and hirsutism in women. Extremely potent CYP 450 inducer
Uses: partial and tonic clonic, more effective in children

Question 4

Phenobarbital

Answer 4

MOA: increase the duration of GABA channel opening
Adverse effects: tolerance, addiction, sedation
Uses: partial and tonic clonic

Question 5

Benzos

Answer 5

MOA: increase the channel opening of GABA channels, leading to hyperpolarization of neurons
Adverse effects: tolerance, sedition
Uses: alcohol withdrawal (diazepam), partial and tonic clonic seizures. DRUG OF CHOICE FOR STATUS EPILEPTUS

Question 6

Diazepam

Answer 6

Rapid acting benzo for alcohol withdrawal

Question 7

Lorazepam

Answer 7

Slow acting benzo that is subjected to phase II metabolism, so there is less drug-drug interaction

Question 8

Ethosuxamide

Answer 8

MOA: inhibits t-type calcium channels, thus decreasing the release of NTs involved in seizures
Adverse Effects: severe gastric upset
Uses: Absence seizures

Question 9

Valproic acid

Answer 9

MOA: mixed bag, inhibits VDNaC / t-type channels / inhibits the degradation of GABA
Adverse Effects: extremely teratogenic, thrombocytopenia, severe gastric upset
Uses: D.O.C for mixed seizures, all other types