Pharmacotherapy of catamenial epilepsy

Epilepsy affects 50 million people worldwide. Women may be afflicted with catamenial epilepsy, a form of epilepsy related to the menstrual cycle. In catamenial epilepsy, seizures are clustered around the monthly cycle. Despite the availability of several standard and newer antiepileptic drugs, there is no specific and effective therapy for catamenial epilepsy. Moreover, the exact pathophysiology of catamenial seizures remains unclear. It is well known that progesterone possess anticonvulsive properties. The level of this hormone drops near the end of the cycle, leaving women more vulnerable to catamenial epilepsy. Recent studies have shown how progesterone protects women against seizures. Progesterone plays two roles in the brain. First, it binds to progesterone receptors in the brain, which help regulate the reproductive functions. Second, progesterone gets metabolized to allopregnanol-one in the brain called a neurosteroid. We found that allopregnanolone plays a crucial role in seizure protection. The withdrawal from this neurosteroid, which occurs during the menstrual cycle, could provoke seizures. Consequently, we suggest that neurosteroid replacement could be a novel therapeutic approach for catamenial epilepsy.