Skip to main content
Log in

Therapeutic Drug Monitoring of Antiepileptic Drugs in Women with Epilepsy Before, During, and After Pregnancy

  • Review Article
  • Published:
Clinical Pharmacokinetics Aims and scope Submit manuscript

Abstract

During pregnancy, the pharmacokinetics of an antiepileptic drug is altered because of changes in the clearance capacity and volume of distribution. These changes may have consequences for the frequency of seizures during pregnancy and fetal exposure to antiepileptic drugs. In 2009, a review was published providing guidance for the dosing and therapeutic drug monitoring of antiepileptic drugs during pregnancy. Since that review, new drugs have been licensed and new information about existing drugs has been published. With this review, we aim to provide an updated narrative overview of changes in the pharmacokinetics of antiepileptic drugs in women during pregnancy. In addition, we aim to formulate advice for dose modification and therapeutic drug monitoring of antiepileptic drugs. We searched PubMed and the available literature on the pharmacokinetic changes of antiepileptic drugs and seizure frequency during pregnancy published between January 2007 and September 2018. During pregnancy, an increase in clearance and a decrease in the concentrations of lamotrigine, levetiracetam, oxcarbazepine’s active metabolite licarbazepine, topiramate, and zonisamide were observed. Carbamazepine clearance remains unchanged during pregnancy. There is inadequate or no evidence for changes in the clearance or concentrations of clobazam and its active metabolite N-desmethylclobazam, gabapentin, lacosamide, perampanel, and valproate. Postpartum elimination rates of lamotrigine, levetiracetam, and licarbazepine resumed to pre-pregnancy values within the first few weeks after pregnancy. We advise monitoring of antiepileptic drug trough concentrations twice before pregnancy. This is the reference concentration. We also advise to consider dose adjustments guided by therapeutic drug monitoring during pregnancy if the antiepileptic drug concentration decreases 15–25% from the pre-pregnancy reference concentration, in the presence of risk factors for convulsions. If the antiepileptic drug concentration changes more than 25% compared with the reference concentration, dose adjustment is advised. Monitoring of levetiracetam, licarbazepine, lamotrigine, and topiramate is recommended during and after pregnancy. Monitoring of clobazam, N-desmethylclobazam, gabapentin, lacosamide, perampanel, and zonisamide during and after pregnancy should be considered. Because of the risk of teratogenic effects, valproate should be avoided during pregnancy. If that is impossible, monitoring of both total and unbound valproate is recommended. More research is needed on the large number of unclear pregnancy-related effects on the pharmacokinetics of antiepileptic drugs.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1

Similar content being viewed by others

References

  1. Meador KJ, Baker GA, Browning N, et al. Effects of fetal antiepileptic drug exposure: outcomes at age 4.5 years. Neurology. 2012;78:1207–14.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  2. Teramo K, Hiilesmaa V. Pregnancy and fetal complications in epileptic pregnancies. In: Janz D, Dam M, Bossi L, Helge H, Richens A, Schmidt D, editors. Epilepsy, pregnancy, child. New York: Raven Press; 1982. p. 53–9.

    Google Scholar 

  3. Harden CL, Pennell PB, Koppel BS, et al. Practice parameter update: management issues for women with epilepsy—focus on pregnancy (an evidence-based review): vitamin K, folic acid, blood levels, and breastfeeding. Report of the Quality Standards Subcommittee and Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology and American Epilepsy Society. Neurology. 2009;73:142–9.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  4. Voinescu PE, Park S, Chen LQ, et al. Antiepileptic drug clearances during pregnancy and clinical implications for women with epilepsy. Neurology. 2018;91(13):e1228–36. https://doi.org/10.1212/WNL.0000000000006240.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  5. Tomson T, Landmark CJ, Battino D. Antiepileptic drug treatment in pregnancy: changes in drug disposition and their clinical implications. Epilepsia. 2013;54:405–14.

    Article  CAS  PubMed  Google Scholar 

  6. Patsalos PN, Berry DJ, Bourgeois BF, et al. Antiepileptic drugs: best practice guidelines for therapeutic drug monitoring: a position paper by the subcommission on therapeutic drug monitoring, ILAE Commission on Therapeutic Strategies. Epilepsia. 2008;49:1239–76.

    Article  CAS  PubMed  Google Scholar 

  7. Tomson T, Battino D, Bonizzoni E, et al. Dose-dependent risk of malformations with antiepileptic drugs: an analysis of data from the EURAP epilepsy and pregnancy registry. Lancet Neurol. 2011;10:609–17.

    Article  CAS  PubMed  Google Scholar 

  8. Tomson T, Battino D, Bonizzoni E, et al. Comparative risk of major congenital malformations with eight different antiepileptic drugs: a prospective cohort study of the EURAP registry. Lancet Neurol. 2018;17:530–8.

    Article  CAS  PubMed  Google Scholar 

  9. Briggs GG, Freeman RK, Towers CV. Drugs in pregnancy and lactation: a reference guide to fetal and neonatal risk. Philadelphia: Lippincott Williams and Wilkins; 2017.

    Google Scholar 

  10. Campbell E, Kennedy F, Russell A. Malformation risks of antiepileptic drug monotherapies in pregnancy: updated results from the UK and Ireland Epilepsy and Pregnancy Registers. J Neurol Neurosurg Psychiatry. 2014;85:1029–34.

    Article  CAS  PubMed  Google Scholar 

  11. Holmes L, Harvey E, Coull B. The teratogenicity of anticonvulsant drugs. N Engl J Med. 2001;344:1132–8.

    Article  CAS  PubMed  Google Scholar 

  12. Güveli BT, Rosti RO, Güzeltas A, et al. Teratogenicity of antiepileptic drugs. Clin Psychopharmacol Neurosci. 2017;15:19–27.

    Article  PubMed  PubMed Central  Google Scholar 

  13. Meador KJ, Baker GA, Browning N, et al. Foetal antiepileptic drug exposure and verbal versus non-verbal abilities at three years of age. Brain. 2011;134:396–404.

    Article  PubMed  PubMed Central  Google Scholar 

  14. uptodate.com. Available from: https://www.uptodate.com/contents/search. Accessed 21 June 2018.

  15. Johnson EL, Stowe ZN, Ritchie JC, et al. Carbamazepine clearance and seizure stability during pregnancy. Epilepsy Behav. 2014;33:49–53.

    Article  PubMed  PubMed Central  Google Scholar 

  16. Reisinger TL, Newman M, Loring DW, et al. Antiepileptic drug clearance and seizure frequency during pregnancy in women with epilepsy. Epilepsy Behav. 2013;29:13–8.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  17. Battino D, Tomson T, Bonizzoni E, et al. Seizure control and treatment changes in pregnancy: observations from the EURAP epilepsy pregnancy registry. Epilepsia. 2013;54:1621–7.

    Article  CAS  PubMed  Google Scholar 

  18. Thomas S, Syan U, Devi J. Predictors of seizures during pregnancy in women with epilepsy. Epilepsia. 2012;53:2010–3.

    Article  Google Scholar 

  19. Öhman I, Sabers A, de Flon P, et al. Pharmacokinetics of topiramate during pregnancy. Epilepsy Res. 2009;87:124–9.

    Article  CAS  PubMed  Google Scholar 

  20. Patsalos PN, Gougoulaki M, Sander JW. Perampanel serum concentrations in adults with epilepsy: effect of dose, age, sex and concomitant anti-epileptic drugs. Ther Drug Monit. 2016;38:358–64.

    Article  CAS  PubMed  Google Scholar 

  21. López-Fraile IP, Cid AO, Juste AO, et al. Levetiracetam plasma level monitoring during pregnancy, delivery, and postpartum: clinical and outcome implications. Epilepsy Behav. 2009;15:372–5.

    Article  PubMed  Google Scholar 

  22. Sabers A, Buchholt J, Uldall P, et al. Lamotrigine plasma levels reduced by oral contraceptives. Epilepsy Res. 2001;47:151–4.

    Article  CAS  PubMed  Google Scholar 

  23. Sabers A, Ohman I, Christensen J, et al. Oral contraceptives reduce lamotrigine plasma levels. Neurology. 2003;61:570–1.

    Article  CAS  PubMed  Google Scholar 

  24. Vajda F, O’Brien T, Lander C, et al. The efficacy of the newer antiepileptic drugs in controlling seizures in pregnancy. Epilepsia. 2014;55:1229–34.

    Article  CAS  PubMed  Google Scholar 

  25. Öhman I, Beck O, Vitols S. Plasma concentrations of lamotrigine and its 2-N-glucuronide metabolite during pregnancy in women with epilepsy. Epilepsia. 2008;49:1075–80.

    Article  CAS  PubMed  Google Scholar 

  26. Pennell PB, Peng L, Newport DJ, et al. Lamotrigine in pregnancy: clearance, therapeutic drug monitoring, and seizure frequency. Neurology. 2008;70:2130–6.

    Article  CAS  PubMed  Google Scholar 

  27. Wegner I, Edelbroek P, De Haan GJ, et al. Drug monitoring of lamotrigine and oxcarbazepine combination during pregnancy. Epilepsia. 2010;51:2500–2.

    Article  PubMed  Google Scholar 

  28. Sabers A, Petrenaite V. Seizure frequency in pregnant women treated with lamotrigine monotherapy. Epilepsia. 2009;50:2163–6.

    Article  PubMed  Google Scholar 

  29. Reimers A, Brodtkorb E. Second-generation antiepileptic drugs and pregnancy: a guide for clinicians. Expert Rev Neurother. 2012;12:707–17.

    Article  CAS  PubMed  Google Scholar 

  30. Polepally AR, Pennell PB, Brundage RC, et al. Model-based lamotrigine clearance changes during pregnancy: clinical implication. Ann Clin Transl Neurol. 2014;1:99–106.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  31. Fotopoulou C, Kretz R, Bauer S, et al. Prospectively assessed changes in lamotrigine-concentration in women with epilepsy during pregnancy, lactation and the neonatal period. Epilepsy Res. 2009;85:60–4.

    Article  CAS  PubMed  Google Scholar 

  32. Tomson T, Battino D. Pharmacokinetics and therapeutic drug monitoring of newer antiepileptic drugs during pregnancy and the puerperium. Clin Pharmacokinet. 2007;46:209–19.

    Article  CAS  PubMed  Google Scholar 

  33. Novy J, Hubschmid M, Michel P, et al. Impending status epilepticus and anxiety in a pregnant woman treated with levetiracetam. Epilepsy Behav. 2008;13:564–6.

    Article  PubMed  Google Scholar 

  34. Westin A, Reimers A, Helde G, et al. Serum concentration/dose ratio of levetiracetam before, during and after pregnancy. Seizure. 2008;17:192–8.

    Article  PubMed  Google Scholar 

  35. Garrity LC, Turner M, Standridge SM. Increased levetiracetam clearance associated with a breakthrough seizure in a pregnant patient receiving once/day extended-release levetiracetam. Pharmacotherapy. 2014;34:e128–32.

    Article  CAS  PubMed  Google Scholar 

  36. Cappellari AM, Cattaneo D, Clementi E, et al. Increased levetiracetam clearance and breakthrough seizure in a pregnant patient successfully handled by intensive therapeutic drug monitoring. Ther Drug Monit. 2015;37:285–7.

    Article  PubMed  Google Scholar 

  37. Tomson T, Palm R, Källén K, et al. Pharmacokinetics of levetiracetam during pregnancy, delivery, in the neonatal period, and lactation. Epilepsia. 2007;48:1111–6.

    Article  CAS  PubMed  Google Scholar 

  38. Petrenaite V, Sabers A, Hansen-Schwartz J. Seizure deterioration in women treated with oxcarbazepine during pregnancy. Epilepsy Res. 2009;84:245–9.

    Article  CAS  PubMed  Google Scholar 

  39. Westin AA, Nakken KO, Johannessen SI, et al. Serum concentration/dose ratio of topiramate during pregnancy. Epilepsia. 2009;50:480–5.

    Article  CAS  PubMed  Google Scholar 

  40. Ornoy A, Zvi N, Arnon J, et al. The outcome of pregnancy following topiramate treatment: a study on 52 pregnancies. Reprod Toxicol. 2008;25:388–9.

    Article  CAS  PubMed  Google Scholar 

  41. Johannessen Landmark C, Huuse Farmen A, Larsen Burns M, et al. Pharmacokinetic variability of valproate during pregnany: implications for the use of therapeutic drug monitoring. Epilepsy Res. 2018;141:31–7.

    Article  CAS  PubMed  Google Scholar 

  42. Reimers A, Helde G, Becser Andersen N, et al. Zonisamide serum concentrations during pregnancy. Epilepsy Res. 2018;144:25–9.

    Article  CAS  PubMed  Google Scholar 

  43. Oles KS, Bell WL. Zonisamide concentrations during pregnancy. Ann Pharmacother. 2008;42:1139–41.

    Article  CAS  PubMed  Google Scholar 

  44. Anderson GD. Pregnancy-induced changes in pharmacokinetics: a mechanistic-based approach. Clin Pharmacokinet. 2005;44:989–1008.

    Article  CAS  PubMed  Google Scholar 

  45. Wegner I, Edelbroek P, Bulk S, et al. Lamotrigine kinetics within the menstrual cycle, after menopause, and with oral contraceptives. Neurology. 2009;73:1388–93.

    Article  CAS  PubMed  Google Scholar 

  46. Herzog AG, Blum AS, Farina EL, et al. Valproate and lamotrigine level variation with menstrual cycle phase and oral contraceptive use. Neurology. 2009;72:911–4.

    Article  CAS  PubMed  Google Scholar 

  47. Thangaratinam S, Marlin N, Newton S, et al. AntiEpileptic drug Monitoring in PREgnancy (EMPiRE): a double-blind randomised trial on effectiveness and acceptability of monitoring strategies. Health Technol Assess. 2018;22:1–152.

    Article  PubMed  PubMed Central  Google Scholar 

  48. FDA, CDER, CVM. Bioanalytical method validation guidance for industry. Silver Spring: Food and Drug Administration (FDA), Center for Drug Evaluation and Research (CDER) and Center for Veterinary Medicine (CVM); 2018.

  49. EMA. Guideline on bioanalytical method validation. Eur Med Agency Comm Med Prod Hum Use. 2015;44:1–23.

  50. Art. 3 van het Besluit Geneesmiddelenwet. 2018. Available from: http://wetten.overheid.nl/BWBR0021672/2018-01-01#Paragraaf2. Accessed 22 Nov 2019.

  51. Sabers A. Algorithm for lamotrigine dose adjustment before, during, and after pregnancy. Acta Neurol Scand. 2012;126:e1–4.

    Article  CAS  PubMed  Google Scholar 

  52. European Medicines Agency. New measures to avoid valproate exposure in pregnancy endorsed. London: European Medicines Agency (EMA); 2018. p. 1–4.

  53. International League Against Epilepsy (ILAE) and European Academy of Neurology (EAN). Valproate in the treatment of epilepsy in women and girls. Pre-publication summary of recommendations from a joint Task Force of ILAE-Commission on European Affairs and European Academy of Neurology (EAN). 2018. Available from: https://www.ilae.org/files/ilaeGuideline/ValproateCommentILAE-0315.pdf. Accessed 22 Nov 2019.

  54. Hernandez-Diaz S, Smith C, Shen A. Comparative safety of antiepileptic drugs during pregnancy. Neurology. 2012;78:1692–9.

    Article  CAS  PubMed  Google Scholar 

  55. Patsalos PN, Zugman M, Lake C, et al. Serum protein binding of 25 antiepileptic drugs in a routine clinical setting: a comparison of free non-protein-bound concentrations. Epilepsia. 2017;58:1234–43.

    Article  CAS  PubMed  Google Scholar 

  56. Kacirova I, Grundmann M, Brozmanova H. Concentrations of carbamazepine and carbamazepine-10,11-epoxide in maternal and umbilical cord blood at birth: influence of co-administration of valproic acid or enzyme-inducing antiepileptic drugs. Epilepsy Res. 2016;122:84–90.

    Article  CAS  PubMed  Google Scholar 

  57. de Leon J, Spina E, Diaz FJ. Clobazam therapeutic drug monitoring: a comprehensive review of the literature with proposals to improve future studies. Ther Drug Monit. 2013;35:30–47.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  58. Burns M, Baftiu A, Opdal M, et al. Therapeutic drug monitoring of clobazam and its metabolite: impact of age and comedication on pharmacokinetic variability. Ther Drug Monit. 2016;38:350–7.

    Article  CAS  PubMed  Google Scholar 

  59. Shorvon S, Perucca E, Engel J Jr. The treatment of epilepsy. 4th ed. Chichester: Wiley; 2016.

    Google Scholar 

  60. Kacirova I, Grundmann M, Brozmanova H. Serum levels of lamotrigine during delivery in mothers and their infants. Epilepsy Res. 2010;91:161–5.

    Article  CAS  PubMed  Google Scholar 

  61. Lyseng-Williamson K, Yang L. Spotlight on topiramate in epilepsy. CNS Drugs. 2008;22:171–4.

    Article  CAS  PubMed  Google Scholar 

  62. Sills G, Brodie M. Pharmacokinetics and drug interactions with zonisamide. Epilepsia. 2007;48:435–41.

    Article  CAS  PubMed  Google Scholar 

  63. Kawada K, Itoh S, Kusaka T, et al. Pharmacokinetics of zonisamide in perinatal period. Brain Dev. 2002;24:95–7.

    Article  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Elisabeth A. Wammes-van der Heijden.

Ethics declarations

Funding

No external funding was used in the preparation of this article.

Conflict of interest

Inge J. Arfman, Elisabeth A. Wammes-van der Heijden, Peter G.J. ter Horst, Danielle A. Lambrechts, Ilse Wegner, and Daan J. Touw have no conflicts of interest that are directly relevant to the content of this article.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Arfman, I.J., Wammes-van der Heijden, E.A., ter Horst, P.G.J. et al. Therapeutic Drug Monitoring of Antiepileptic Drugs in Women with Epilepsy Before, During, and After Pregnancy. Clin Pharmacokinet 59, 427–445 (2020). https://doi.org/10.1007/s40262-019-00845-2

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s40262-019-00845-2

Navigation