EFFICACY AND SAFETY OF ANTIEPILEPTIC DRUGS DURING PREGNANCY: PHARMACOGENETIC ASPECTS

This paper summarises scientific literature on pharmacotherapy of epilepsy in pregnant women from the perspective of clinical pharmacology. It analyses general principles of antiepileptic therapy in pregnant women. It was demonstrated that the optimal conditions for treating epilepsy during pregnancy involve the use of the minimum dose of an anticonvulsant. The article describes specific pharmacokinetic parameters of antiepileptic drugs (valproic acid, carbamazepine, lamotrigine, phenytoin, phenobarbital) that require adjustment of the dose regimen based on therapeutic drug monitoring. It was demonstrated that carriership of «slow» allelic variants of CYP2C9 is associated with a slowdown in hepatic biotransformation of valproic acid, carbamazepine, topiramate, phenytoin, oxcarbazepine, diazepam, phenobarbital, and primidone, and, consequently, with increased drug concentrations in blood plasma and an increased risk of adverse reactions. Taking into account polymorphism of genes encoding metabolic isoenzymes of traditional antiepileptic drugs, it is recommended for pregnant women and women planning a pregnancy to undergo genotyping. It was demonstrated that polymorphism of the ABCB1 gene and genes of other transport proteins can modify the effect of antiepileptic drugs on the foetus, thus increasing the teratogenic risk.

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