bipolar depression
2 interactions related to bipolar depression
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.
grapefruit + lurasidone
Lurasidone is primarily metabolized by CYP3A4 and is highly sensitive to CYP3A4 inhibitors. The FDA-approved Latuda prescribing information specifically states that grapefruit and grapefruit juice should be avoided in patients taking lurasidone because they inhibit CYP3A4 and can substantially raise lurasidone concentrations.