Medicine & USMLE


  1. Valproic Acid (Valproate)
  2. Carbamazepine
  3. Ethosuximide
  4. Gabapentin
  5. Lamotrigine
  6. Levetiracetam
  7. Barbituates (Phenobarbital, Thiopental)
  8. Topiramate
  9. Vigabatrin


Topiramate is a drug used to treat seizures and headaches. It works by blocking sodium channels in the brain, preventing the generation and propagation of action potentials responsible for seizures. Since topiramate is a broad-spectrum antiepileptic, it can be used to treat a variety of seizures, including focal and generalized seizures. Topiramate may also be used in the preventative treatment of migraine headaches. A major side effect of topiramate to look out for is the development of kidney stones. Low yield nonspecific side effects of topiramate include sedation, slow cognition, weight loss, and glaucoma.

Key Points

  • Topiramate
    • Mechanism
      • Blocks Na+ channels
        • Blocking of sodium ion influx inhibitors depolarization of neuron, inhibiting firing of AP
      • Increases GABA action
      • Also blocks Ca2+ channels
    • Clinical Use
      • Broad-spectrum antiepileptic
        • Used to treat focal (partial) and generalized (tonic-clonic) seizures
      • Migraine prophylaxis
    • Adverse Effects
      • Kidney stones
      • Sedation, slow cognition (word-finding difficulties), weight loss, glaucoma (rare)