A candidate gene study of antiepileptic drug tolerability and efficacy identifies an association of<i>CYP2C9</i>variants with phenytoin toxicity

Our study is the first comprehensive candidate gene association study in epilepsy pharmacogenetics. Our results confirm the role of CYP2C9 variants in PHT toxicity. No other definite associations were identified. Large-scale efforts are needed to unravel the genetic determinants of AED response.