Topiramate

Administration

  • Type: antiepileptics
  • Dosage Forms: 25mg, 50mg, 100mg, 200mg tabs; 15mg, 25mg caps
  • Routes of Administration: PO
  • Common Trade Names: Topamax

Adult Dosing

Partial Seizures

  • monotherapy
    • Dose: 200mg PO bid; Start: 25mg PO BID x1wk, increase by 50mg/day qwk until 100mg PO bid, then increase by 100mg/day qwk; Info: doses >400mg/day rarely more effective
  • adjunct therapy
    • Dose: 100-200mg PO bid; Start: 25mg PO QD-bid x1wk, increase by 25-50mg/day qwk; Info: doses >400mg/day rarely more effective

seizures, primary generalized tonic clonic

  • monotherapy
    • Dose: 200mg PO bid; Start: 25mg PO BID x1wk, increase by 50mg/day qwk until 100mg PO bid, then increase by 100mg/day qwk; Info: doses >400mg/day rarely more effective
  • adjunct therapy
    • Dose: 200mg PO bid; Start: 25mg PO QD-bid x1wk, increase by 25-50mg/day qwk; Info: doses >400mg/day rarely more effective

Seizures, Lennox-Gastaut

  • adjunct therapy
    • Dose: 100-200mg PO bid; Start: 25mg PO QD-bid x1wk, increase by 25-50mg/day qwk; Info: doses >400mg/day rarely more effective

Migraine headache, prophylaxis

  • 50mg PO bid
    • Start: 25mg PO qhs x1wk, increase by 25mg/day qwk; Max: 200mg/day

Pediatric Dosing

Special Populations

Renal Dosing

  • Adult: CrCl 10-70: decrease dose 50%; CrCl <10: decrease dose 75%; HD: give supplement
  • Pediatric:

Hepatic Dosing

  • Adult: not defined; caution advised
  • Pediatric:

Contraindications

  • Allergy to class/drug

Adverse Reactions

Serious

Common

Pharmacology

  • Half-life:
  • Metabolism:
  • Excretion:

Mechanism of Action

  • Unclear, however has activity on voltage-gated sodium channels, calcium channels, GABA-A receptors, and carbonic anhydrase enzymes

Comments

See Also

References