Ascorbic Acid (Vitamin C) and Ethinyl Estradiol: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Ethinyl Estradiol
No brand names on recordAscorbic Acid (Vitamin C)
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
Increased ethinyl estradiol exposure
Interaction Deep Dive
Concomitant use of ascorbic acid and ethinyl estradiol (hormonal contraceptive) may cause elevated plasma concentrations of ethinyl estradiol, possibly by inhibition of conjugation1.
Why it happens (mechanism)
Inhibition of conjugation of ethinyl estradiol
Common questions
Can I take Ascorbic Acid (Vitamin C) and Ethinyl Estradiol together?
Increased ethinyl estradiol exposure Always confirm with your pharmacist or prescriber before making any change.
How serious is the Ascorbic Acid (Vitamin C) and Ethinyl Estradiol interaction?
It is rated moderate. Can be significant — usually manageable with 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 Ascorbic Acid (Vitamin C) or Ethinyl Estradiol 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 anything you'd monitor while I'm on both?
References (1)
- Product Information: NuvaRing(R) vaginal ring, etonogestrel ethinyl estradiol vaginal ring. Organon & Co. (per FDA), Jersey City, NJ, 2024.
Keep reading about Ethinyl Estradiol
Keep reading about Ascorbic Acid (Vitamin C)
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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