* Valproic acid is principally metabolized by CYP2C9, CYP2C19, CYP2A6 and UDP-glucuronosyltransferases. Valproic acid is an inhibitor of the enzymes CYP2C9, epoxide-hydroxylase and UDP-glucuronosyltransferases.
* Lamotrigine is principally metabolised by UDP-glucuronosyltransferases.
* This combination of drugs may have possible synergistic effects. However, the pharmacokinetic drug interactions will influence the plasma levels. Dose adaptation will be recommended for this combination.{{PossibleSynergisticEffects}}
| start =
* Lamotrigine generally has no significant effect on valproate levels, however caution is recommended.