Medroxyprogesterone and Rufinamide: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Rufinamide
Medroxyprogesterone
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Reduced contraceptive exposure, reduced efficacy of combination contraceptives and an increased risk of breakthrough bleeding/contraceptive failure
Interaction Deep Dive
Avoid coadministration of rufinamide (CYP3A4 inducer) and contraceptives as it may reduce contraceptive exposure and may increase risk of breakthrough bleeding1. Concomitant use of rufinamide with hormonal contraceptives may result in decreased contraceptive efficacy. One study demonstrated a decrease in the AUC and Cmax of ethinyl estradiol and norethindrone when rufinamide was administered concurrently. Patients should be advised to use an alternative or backup method of contraception during rufinamide therapy 3 and for 28 days after discontinuation of rufinamide 2.
Why it happens (mechanism)
Induction of CYP3A4-mediated metabolism of contraceptive
Literature reports
1 report — tap to read
a) When oral rufinamide 800 mg was given twice daily for 14 days with an oral contraceptive containing ethinyl estradiol 35 mcg and norethindrone 1 mg, the mean ethinyl estradiol AUC and Cmax decreased by 22% and 18%, respectively, and the mean norethindrone AUC and Cmax decreased by 14% and 18%, respectively 3.
Common questions
Can I take Medroxyprogesterone and Rufinamide together?
Reduced contraceptive exposure, reduced efficacy of combination contraceptives and an increased risk of breakthrough bleeding/contraceptive failure Always confirm with your pharmacist or prescriber before making any change.
How serious is the Medroxyprogesterone and Rufinamide interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Medroxyprogesterone or Rufinamide need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (3)
- Product Information: FEMLYV orally disintegrating tablets, norethindrone acetate, ethinyl estradiol orally disintegrating tablets. Millicent U.S. Inc (per FDA), East Hanover, NJ, 2024. DailyMed
- Product Information: NEXPLANON(R) subdermal implant, etonogestrel subdermal implant. Merck Sharp & Dohme Corp. (per FDA), Whitehouse Station, NJ, 2017.
- Product Information: BANZEL(TM) oral tablets, rufinamide oral tablets. Eisai, Inc, Woodcliff Lake, NJ, 2008. DailyMed
Keep reading about Rufinamide
Keep reading about Medroxyprogesterone
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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