Seizure exacerbation associated with inhibition of progesterone metabolism

Abstract

The reduced progesterone metabolite tetrahydroprogesterone is a potent positive modulator of GABA_A chloride conductance that exerts powerful neuroinhibitiory and antiseizure 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. Ann Neurol 2003;53:390–391