Authors :
Nadejda Khmelev, MD – Kaplan Hospital
Firas Fahoum, MD – Faculty of Medical & Health Sciences, Tel Aviv University; Neurological Institute, Tel Aviv Sourasky Medical Center
Presenting Author: Lilach Goldstein, md – TLVMC
Rationale:
Lamotrigine (LTG) and Levetiracetam (LEV) are anti-seizure medications (ASMs) widely used for the treatment of women with epilepsy (WWE) of childbearing age due to low teratogenic potential. Physiological changes during gestation alter the pharmacokinetic properties of these drugs and enhance their clearance. Hence, drug level monitoring and frequent dose adjustments are required to avoid a decline in serum levels that could result in poor seizure control. During the postpartum period, the physiological changes are reversed and the clearance of these antiseizure medications trends back to pre-pregnancy rate. The rapid changes in metabolism postpartum makes monitoring of drug levels and dose adjustments challenging. A delay in decreasing the dose could result in drug toxicity. The ideal rate of dose reduction following delivery is yet to be determined.
Methods:
We retrospectively examined the medical records of pregnant WWE who were followed at Tel Aviv Sourasky Medical Center between the years of 2018-2023. At the beginning of the study period, patients were instructed to continue therapeutic drug monitoring (TDM) of ASMs following delivery. Starting October 2020, an empiric taper down regimen following delivery was implemented with dosing adjustments scheduled for 1 day, 1 week and 3 weeks postpartum. An individualized regimen was provided for each patient on her last prenatal visit. We recorded ASM dose, serum levels, and self-reports of seizures frequency and side effects.
Results:
Eighty-nine pregnancies of 80 WWE were included. At the time of delivery, forty-five were treated with LEV, 40 with LTG and 4 with a combination of both ASMs. In 29 pregnancies, patients continued therapeutic drug monitoring (TDM) during the post-partum period and in 60 pregnancies, patients were instructed to follow an empiric down titration regimen. Among WWE who were seizure free prior to and during pregnancy with available data about seizure frequency postpartum, none out of 44 on the empiric group and 2 out of 16 in the TDM group had a seizure during the down titration period. Among patients with documentation of side effects, 6 of 54 patients among the empiric group reported having side effects postpartum, vs. 5 of 21 among the TDM group.
Conclusions:
Empiric schedule for postpartum dose reduction was not associated with increased risk of seizure exacerbation and was well tolerated with minimal side effects.
Funding: none