Estradiol and Voriconazole: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Voriconazole
Estradiol
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 voriconazole exposure, increased ethinyl estradiol and norethindrone exposure
Interaction Deep Dive
Coadministration of voriconazole with an oral combination contraceptive containing ethinyl estradiol and norethindrone has resulted in increased exposure of , ethinyl estradiol, and norethindrone12. Concomitant use of voriconazole with oral contraceptive (CYP3A4/CYP2C19 inhibitors) may increase voriconazole exposure. Adjust voriconazole dosage 3. When these agents are coadministered, monitor patients for adverse events related to voriconazole (peripheral edema, visual disturbance) and ethinyl estradiol/norethindrone (abnormal menstruation, breast tenderness, edema) 2.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of voriconazole; inhibition of CYP2C19-mediated metabolism of voriconazole; altered CYP450-mediated metabolism of ethinyl estradiol, and norethindrone
Literature reports
1 report — tap to read
a) Concomitant administration of voriconazole and an oral contraceptive in 16 healthy women resulted in increased systemic exposure to all analytes relative to monotherapy, according to an open-label, fixed-sequence, three-period study. In period 1, women (mean age, 25.9 years; range, 19 to 36 years) received voriconazole 400 mg every 12 hours on day 1 and 200 mg every 12 hours on days 2 through 4. During period 2, women were given an oral contraceptive containing ethinyl estradiol 0.035 mg/norethindrone 1 mg every 24 hours on days 12 through 32. In period 3, subjects received combination voriconazole 400 mg every 12 hours on day 57, 200 mg every 12 hours on days 58 through 60, and an oral contraceptive every 24 hours on days 40 through 60. With concurrent administration, there were mean increases in voriconazole AUC and Cmax of 46% (90% confidence interval (CI), 32% to 61%) and 14% (90% CI, 3% to 27%), respectively, compared with monotherapy. Ethinyl estradiol AUC and Cmax increased 61% (90% CI, 50% to 72%) and 36% (90% CI, 28% to 45%), respectively. Norethindrone AUC and Cmax increased 53% (90% CI, 44% to 64%) and 15% (90% CI, 3% to 28%), respectively. Regardless of causality, the most commonly-reported adverse events during combination therapy were headache, abnormal vision, dizziness, nausea, and chromatopsia 2.
Common questions
Can I take Estradiol and Voriconazole together?
Increased voriconazole exposure, increased ethinyl estradiol and norethindrone exposure Always confirm with your pharmacist or prescriber before making any change.
How serious is the Estradiol and Voriconazole interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "delayed". Effects tend to build up gradually over days to weeks.
How strong is the evidence for this interaction?
The evidence is graded "established". Well documented — supported by controlled studies or strong clinical data.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Estradiol or Voriconazole 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: LOESTRIN(R) 24 Fe oral tablets, norethindrone acetate ethinyl estradiol oral tablets, ferrous fumarate oral tablets. Teva Pharmaceuticals USA Inc (per FDA), Parsippany, NJ, 2023. DailyMed
- Andrews E, Damle BD, Fang A, et al: Pharmacokinetics and tolerability of voriconazole and a combination oral contraceptive co-administered in healthy female subjects. Br J Clin Pharmacol 2008; 65(4):531-539. PubMed
- Product Information: VFEND(R) oral tablets, oral suspension, intravenous injection, voriconazole oral tablets, oral suspension, intravenous injection. Roerig (per FDA), New York, NY, 2025. DailyMed
Keep reading about Voriconazole
Keep reading about Estradiol
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.
Check another combination
Our instant two-drug interaction checker is almost here.
Still have questions about this combination?
Every question gets a real answer from a licensed pharmacist — free, and usually within a day.
Ask the pharmacist