Seizure exacerbation associated with inhibition of progesterone metabolism

Ann Neurol. 2003 Mar;53(3):390-1. doi: 10.1002/ana.10508.


The reduced progesterone metabolite tetrahydroprogesterone is a potent positive modulator of GABA(A) chloride conductance that exerts powerful neuroinhibitiory and anti-seizure effects in animal models. Cyclic natural progesterone use may lessen seizure frequency in women with catamenial seizure exacerbation. We report a case in which efficacy was eliminated during concomitant treatment with a reductase inhibitor. The observation suggests that a reduced metabolite, rather than progesterone itself, was responsible for improved seizure control.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Enzyme Inhibitors / adverse effects
  • Female
  • Finasteride / adverse effects
  • Humans
  • Menstrual Cycle / metabolism
  • Pregnanolone / metabolism
  • Progesterone / antagonists & inhibitors*
  • Progesterone / metabolism*
  • Seizures / chemically induced
  • Seizures / drug therapy
  • Seizures / metabolism*
  • Statistics, Nonparametric


  • Enzyme Inhibitors
  • Progesterone
  • Finasteride
  • Pregnanolone