Association of Levetiracetam Concentration With Seizure Frequency in Pregnant Women With Epilepsy.

All in all, we recommend therapeutic drug monitoring for all pregnant patients on LEV as the concentrations of LEV significantly decrease throughout most months of pregnancy. However, this decrease in LEV concentration was only significantly correlated with seizure deterioration in patients who had a seizure in the year preceding the pregnancy . Therefore, we suggest more careful monitoring of non-seizure free patients as they are at higher risk for experiencing an increase of seizure frequency. For this group, we advise physicians to keep LEV concentration above 65% of the preconceptional concentration. For seizure free patients we recommend a LEV threshold value of approximately 46% of the preconceptional concentration.