Can I take folic acid at the same time as methotrexate?
Yes. Many clinicians advise taking folic acid the day of methotrexate or on the days it is prescribed, because folic acid helps reduce side effects such as mouth sores and some blood count effects without blunting methotrexate’s overall benefit in rheumatoid arthritis, psoriasis, or other inflammatory uses. (The exact timing depends on the methotrexate schedule and the folic acid dose.)
What timing schedules are commonly used?
Common real-world approaches include:
- Taking folic acid regularly on non–methotrexate days (for example, daily except the day you take methotrexate).
- Taking folic acid daily, including the day of methotrexate.
- Taking folic acid in a weekly pattern separate from methotrexate.
Because different conditions and dosing regimens use different strategies, the safest rule is to follow the plan your prescriber gave you for your specific methotrexate regimen.
What if my methotrexate dose is weekly?
With weekly methotrexate, folic acid is often prescribed as either:
- Daily folic acid throughout the week (including the methotrexate day), or
- Daily folic acid except on the methotrexate day.
If you were told to “skip the folic acid on methotrexate day,” that usually means: take folic acid the day before and after, not the same day.
What if I miss a dose of folic acid or methotrexate?
- If you miss folic acid: take it when you remember unless your clinician told you to skip on certain days; don’t double up unless instructed.
- If you miss methotrexate: contact your prescriber for guidance. Weekly methotrexate has specific “missed dose” rules that depend on how long ago the scheduled dose was.
Are there safety issues with folic acid and methotrexate?
Folic acid is generally used specifically to reduce methotrexate toxicity, so it’s commonly continued long-term with methotrexate. Still, talk to your clinician before changing timing or dose, especially if you have:
- Kidney disease (methotrexate clearance can be affected)
- Significant low blood counts or recurrent mouth sores
- Other medications that affect folate or blood counts
Does folic acid ever interfere with methotrexate?
Folic acid is intended to protect normal cells from some of methotrexate’s side effects while methotrexate treats the underlying disease. The key is using the folic acid plan your prescriber recommends, not a high-dose change on your own.
Quick practical rule
Use the instruction you were given (for example, “skip folic acid on methotrexate day” versus “take daily”), because weekly methotrexate schedules are often paired with either same-day or separate-day folic acid routines.
If you tell me your methotrexate schedule (weekly or daily) and what directions you were given for folic acid (dose and whether to skip methotrexate day), I can help you translate that into an exact day-by-day timing plan.