Pharmacotherapeutic Issues for Women of Childbearing Age with Epilepsy

Abstract

James W McAuley BSPharm PhD, Assistant Professor of Pharmacy Practice and Administration and Neurology, Colleges of Pharmacy and Medicine, The Ohio State University OBJECTIVE: To provide an overview of key pharmacotherapeutic issues in epilepsy for the woman of childbearing potential. DATA SOURCES: A MEDLINE search (1966–1997) was done to identify pertinent literature. Chapters in epilepsy textbooks, pregnancy registries, and their respective bibliographies were also evaluated. STUDY SELECTION AND DATA EXTRACTION: All identifiable sources written in English were evaluated. DATA SYNTHESIS: Epilepsy is a common neurologic disorder. It is estimated that nearly 1 million American women of childbearing age have epilepsy. There are many women's health issues in epilepsy. These include menstrual cycle influences on seizure activity, contraceptive–antiepileptic drug interactions, pharmacokinetic changes during pregnancy, teratogenicity of antiepileptic drugs, breast-feeding, and quality of life. These issues challenge both the woman with epilepsy and the many healthcare providers involved in her care. This article reviews these issues and makes recommendations. It addresses both the first-generation antiepileptic drugs (phenobarbital, phenytoin, carbamazepine, valproic acid) and the newer or second-generation agents (felbamate, gabapentin, lamotrigine, topiramate, tiagabine). CONCLUSIONS/RECOMMENDATIONS: Drug interactions between enzyme-inducing antiepileptic drugs and contraceptives are well documented. Higher doses of oral contraceptives or a second contraceptive method are suggested if epileptic women use an enzyme-inducing antiepileptic drug. Planned pregnancy is highly recommended and counseling before conception is crucial. Prepregnancy counseling should include, but is not limited to, folic acid supplementation, optimal control of seizure activity, monotherapy with the lowest effective antiepileptic drug dose, and medication adherence. Patient information should be provided about the risk of teratogenicity and the importance of prenatal care. Antiepileptic drug dosage adjustments may be necessary and should be based on clinical symptoms, not solely on serum drug concentrations. While the future holds promise for many aforementioned women's issues in epilepsy, many questions remain to be answered.