FRCA Notes

Epilepsy during pregnancy

Resources

  • Epilepsy complicates 0.5% of pregnancies
  • 1/3rd of patients experience worsening seizure frequency, owing to:
    • Hormonal changes
    • Altered pharmacokinetics of anti-epileptic drugs
    • Poor concordance with anti-epileptics
  • 1/3rd of patients experience no change in seizure frequency
  • 1/3rd of patients experience an improvement in seizure frequency
  • There is an increased incidence of congenital abnormalities with anti-epileptic drugs
  • Valproate is the most teratogenic of the lot
  • Patients should have their medication altered by a Neurologist; the lowest effective dose of a single agent should be used

  • One should avoid pethidine, whose active metabolite norpethidine is pro-convulsant; other peripartum analgesics are mostly fair game
  • Tramadol, a technically viable although seldom-used post-operative analgesic, lowers the seizure threshold - especially in combination with SSRIs or TCAs
  • Tranexamic acid can induces seizures although this is unlikely in the 1-2g dosing regimen one might use in Obstetrics

  • If seizures occur they should be treated in the standard fashion (see notes from the ICM section on status epilepticus)
  • One should be mindful that seizures can be a manifestation of eclampsia, which should be excluded or treated accordingly