Table 7. Antiepileptic drugs and their effect on enzyme induction and contraceptive reliability.
Enzyme induction | Drugs | Contraceptive reliability |
Marked | barbiturates, carbamazepine, felbamate, oxcarbazepine, phenytoin, primidone, clonazepam, topiramate | not reliable |
Reciprocal interaction | lamotrigine (dose must be raised; EE induces metabolism of lamotrigine and lamotrigine induces metabolism of LNG) | beware of possible effect |
None | valproic acid, gabapentin, levetiracetam, tiagabine, vigabatrin, zonisamide, pregabalin | fully reliable |
EE, ethinyl estradiol; LNG, levornogestrel; LTG, lamotrigine