1 interaction related to lamotrigine
Lamotrigine inhibits dihydrofolate reductase, the enzyme that converts dihydrofolate to active tetrahydrofolate, and high-dose folic acid supplementation has been shown to blunt lamotrigine's antidepressant effect in bipolar depression (CEQUEL trial), particularly in COMT Met allele carriers. The interaction is pharmacodynamic rather than pharmacokinetic, so lamotrigine blood levels remain unchanged.