What the FDA labels say about taking them together
Folic acid and methotrexate
Folic acid's FDA label of July 24, 2026 names methotrexate in its drug interactions section; the methotrexate labels PlainMeds reads (4) do not name folic acid. The folic acid label: “Folate deficiency may result from increased loss of folate, as in renal dialysis and/or interference with metabolism; the administration of anticonvulsants, such as diphenylhydantoin, primidone, and barbiturates; …”
Check it at the source: the folic acid FDA label on DailyMed (effective July 24, 2026, Rising Pharma Holdings, Inc.); the methotrexate FDA label on DailyMed (effective May 27, 2026, Accord Healthcare Inc.).
What does the folic acid label say about methotrexate?
Folic acid label, drug interactionsFolate deficiency may result from increased loss of folate, as in renal dialysis and/or interference with metabolism (e.g., folic acid antagonists such as methotrexate); the administration of anticonvulsants, such as diphenylhydantoin, primidone, and barbiturates; alcohol consumption and, especially, alcoholic cirrhosis; and the administration of pyrimethamine and nitrofurantoin.
Folic Acid label (Ayurax, LLC, February 11, 2026), drug interactionsAcid on Other Drugs Folic acid may interfere with gastrointestinal absorption of methotrexate.
Source: FDA drug label (Folic Acid, NDA216395), Ayurax, LLC, effective February 11, 2026 (SPL set 96618bf8-6c03-4df3-9896-b7ef27ca392a), via openFDA
Source: FDA drug label (Folic Acid), Rising Pharma Holdings, Inc., effective July 24, 2026 (SPL set 0baa10dd-6d1d-4946-8236-566451132da3), via openFDA; the full label on DailyMed
What does the methotrexate label say about folic acid?
Methotrexate's label (effective May 27, 2026) and its 3 other brand-application labels do not name folic acid in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Methotrexate), Accord Healthcare Inc., effective May 27, 2026 (SPL set 874c7f43-a3be-4236-89cc-24c44e3c5813), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Folic acid | Methotrexate | |
|---|---|---|
| Labeled for | n/a | Rheumatoid arthritis, Psoriasis, Leukemia, lymphoma and myeloma, Breast cancer |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.0201 per tablet 1 mg tablet | $0.158 per tablet 2.5 mg tablet |
| Shortage now | No current entry | In shortage |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once