Antiepileptics- Dr. Masserano

Question 1

Mechanism of action of Carbamazepine, Oxcarbazepine, Phenytoin, Fosphenytoin, Zonisamide, Lamotrigine, Valproic acid, Topiramate, Rufinamide, Lacosamide

Answer 1

• Prolong the inactivation period of Na+ channels

- Prolonging the refractory period, inhibiting repetitive firing of neruons

Question 2

Mechanism of action of Benzodiazepines, Barbiturates, Vigabatrin, Tiagabine

Answer 2

-Enhance neuronal GABA inhibition

Question 3

Mechanism of action of Levetiracetam, felbamate, topiramate, perampanel

Answer 3

-Reduce glutamate exictiation

Question 4

Mechanism of action of ethosuximide, valproic acid, Gabapentin, and pregabalin

Answer 4

-Inhibit Ca++ currents

Question 5

Mechanism of action of exogabine

Answer 5

-Enhances outward potassium currents

Question 6

Which AEDs decrease the efficacy of Oral contraceptives and can lead to decrease in blood calcium levels

Answer 6

• Phenytoin
• Carbamazepine
• Phenobarbital
• Topiramate
• Oxcarbazepine

Question 7

Which AEDs can be used to treat Trigeminal Neuralgia

Answer 7

• Phenytoin
• Caramazepine
• Oxcarbazepine
• Lamotrigine

Question 8

Which AEDs inhibit warfarin metabolism

Answer 8

• Valproic acid

- Phenytoin

Question 9

Syndrome of Inappropriate Antidiuretic Hormone (SIADH)

Answer 9

• Leads to hyponatremia

- Caused by Carbamazepine and Oxcarbazepine

Question 10

Zonisamide (Zonegran) mechanism of action

Answer 10

-Prolongs the inactivation period of Na+ Channels

Question 11

Topiramate (Topomax) two mechanisms of action

Answer 11

• AMPA/Kainate antagonist

- Prolongs the inactivation period of Na+ channels

Question 12

Safest AEDs in pregnancy

Answer 12

• Lamotrigine

- Levetiracetam