carbamazepine, carbamazepine-10, 11-epoxide, delivery, therapeutic drug monitoring, drug-drug interaction, epilepsy

Carmbamazepine is one of the three most frequently prescribed antiepileptic frugs in pregnancy. However, data relating to both carbamazepine and carbamazepine-10, 11-epoxide transplacental passage remain sparse. We have analysed in a cohort of 114 women carbamazepine and carbamazepine-10, 11-epoxide levels in maternal and umbilical cord serum at birth during 25 years retrospectively. The data showed the wide interindividual variability of the ratio of the umbilical cord/maternal level of both carbamaziepine and carbamazepine-10,11-epoxide. it is the first study show-ing the significant increase of the ratio of umbilical cord/maternal level of carbamazepine-10, 11-epoxide and carbamazepine-10,11-epoxide/carbamazepine ratio not only in maternal serum but also in umbilical cord in addition of valproic acid. The present study demonstates thal a concomitant administration of enzyme-inducing antiepileptics and valproic acid increases the maternal apparent oral clearance of carbamazepine significantly.