dihydrofolate reductase
2 interactions related to dihydrofolate reductase
lamotrigine + folate
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.
lamotriginefolatefolic acidbipolar depressionanticonvulsantdihydrofolate reductasecequelepilepsy
methotrexate + folate
Methotrexate works by inhibiting dihydrofolate reductase, depleting active folate and causing GI, mucosal, and hepatic side effects. Folic acid supplementation reduces those side effects by 26-77% without compromising efficacy, but must be timed correctly to avoid blunting the drug's action.
methotrexatefolatefolic acidrheumatoid arthritisdihydrofolate reductaseside effectssupplementationtiming