Serum concentration/dose ratio of levetiracetam before, during and after pregnancy

Seizure. 2008 Mar;17(2):192-8. doi: 10.1016/j.seizure.2007.11.027. Epub 2008 Jan 3.


Purpose: To investigate changes in levetiracetam (LEV) serum concentration/dose ratio (C/D-ratio) in relation to pregnancy.

Methods: Altogether 21 consecutive pregnancies in 20 women with epilepsy receiving LEV during gestation were studied retrospectively. The main target variable was the C/D-ratio before and during pregnancy, and in the post partum period. Secondary target variables were changes in LEV dose, concomitant use of other antiepileptic drugs and seizure frequency. Student's paired t-test and two-sample t-test for independent samples were used to test for statistically significant changes in C/D-ratio means.

Results: Mean C/D-ratio in the third trimester was 50% of the mean C/D-ratio at baseline (p<0.001, n=11). Baseline levels were reached within the first weeks after pregnancy. The interindividual variability was pronounced.

Conclusions: Serum concentrations of LEV declined significantly in the third trimester of pregnancy and increased rapidly after delivery.

MeSH terms

  • Adult
  • Anticonvulsants / blood*
  • Anticonvulsants / therapeutic use
  • Epilepsy / blood*
  • Epilepsy / drug therapy
  • Female
  • Humans
  • Levetiracetam
  • Piracetam / analogs & derivatives*
  • Piracetam / blood
  • Piracetam / therapeutic use
  • Pregnancy / blood*
  • Pregnancy / drug effects
  • Retrospective Studies
  • Time Factors


  • Anticonvulsants
  • Levetiracetam
  • Piracetam