Real-world prescribing trends of valproate in women with epilepsy in Korea

Avoiding valproate is recommended in women of childbearing age due to possible teratogenicity and infertility. We aimed to examine the recent trend of valproate prescriptions in Korea to review the adequacy of anticonvulsant prescriptions in women with epilepsy (WWE). Oral valproate utilization was assessed using nationwide and unselected data from the Korean National Health Insurance Service from 2009 to 2017. The temporal trends of the proportions of valproate prescriptions were analyzed using the Poisson regression model and expressed as average annual percentage change (AAPC). Among the WWE of childbearing age, valproate was prescribed in 37.0% overall and 29.4% as initial prescription in 2017. The proportion of valproate utilization showed a decreasing trend in overall prescription (AAPC = -1.10%) and initial prescription (AAPC = -2.63%). However, the proportion was static over time in the initial monotherapy group (AAPC = -0. 53%), while it was significantly decreasing in the initial polytherapy group (AAPC = -8.25%). A noticeable proportion of WWE was still being prescribed valproate in Korea. In particular, the use of valproate for initial monotherapy has not decreased over the past nine years. This result calls not only for reinforcement of education regarding anticonvulsant selection but also for monitoring the actual prescription.