Folic acid (folate) and Leucovorin interaction
Folic acid (folate) and Leucovorin: the Leucovorin prescribing label flags this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Leucovorin (VYKOURA) label · effective 2026-03-12
VYKOURA is contraindicated in patients who have had a severe hypersensitivity reaction to leucovorin (folinic acid), levoleucovorin, or folic acid [see Warnings and Precautions (5.1) ].
VYKOURA is contraindicated in patients who have had a severe hypersensitivity reaction to leucovorin, levoleucovorin, or folic acid [see Contraindications (4) ].
Risk of Administration Errors In the treatment of accidental overdosages of intrathecally administered folic acid antagonists, do not administer VYKOURA intrathecally.
Folic acid in high doses may reduce the effectiveness of certain antiepileptic drugs (e.g., phenobarbital, phenytoin, and primidone) and thereby increase the frequency of seizures.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.