Estradiol and Isotretinoin: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Isotretinoin
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
Decreased effectiveness of hormonal contraceptives
Interaction Deep Dive
When coadministered with isotretinoin, pharmacokinetic and pharmacodynamic changes to estrogens and progestins are small but highly variable and unpredictable. Pregnancy has been reported in women who have used combined oral contraceptives, as well as topical/injectable/implantable/insertable hormonal birth control products. Such reports have occurred more frequently in those using a single form of contraception. Micro-dosed progestin-only pills elevate the risk of contraceptive failure during concomitant treatment with isotretinoin. During isotretinoin therapy, female patients of child bearing potential must use 2 forms of contraception simultaneously, one form should include: tubal ligation, partner's vasectomy, intrauterine devices, birth control pills, or topical/injectable/implantable/insertable hormonal birth control products123.
Why it happens (mechanism)
Unknown
Literature reports
2 reports — tap to read
a) Isotretinoin did not interact with oral contraceptives in a study. Nine women taking isotretinoin 0.5 mg/kg for severe pustular acne received oral contraceptives (brand unknown) for at least three months prior to starting isotretinoin therapy. Plasma concentrations of ethinyl estradiol and levonorgestrel in the control cycle and in two cycles after starting isotretinoin were similar as determined by radioimmunoassay 4.
b) Pharmacokinetic and pharmacodynamic changes were inconsistent and relatively small when isotretinoin was given with a combination ethinyl estradiol/norethindrone product. In a single-center, open-label drug interaction study, 26 healthy women completed a study in which they were given ethinyl estradiol/norethindrone oral contraceptive (OC) triphasic tablets (35 micrograms and 0.5/0.75/1 milligrams, respectively) daily. At the start of the third month and after the possibility of pregnancy was ruled out, participants were also given isotretinoin 1 milligrams/kilogram/day in two divided doses to complete 16 to 20 weeks of isotretinoin treatment for severe, recalcitrant nodular acne. Ethinyl estradiol and norethindrone plasma concentrations were slightly reduced (9% and 11%, respectively) during the OC plus isotretinoin phase compared with the OC alone phase; patient variability was high, however. Follicle stimulating hormone concentration declined 44% (p=0.03) when isotretinoin was added to the regimen, again with a high degree of variability; serum progesterone and luteinizing hormone levels were unchanged. No pregnancies were reported 5.
Common questions
Can I take Estradiol and Isotretinoin together?
Decreased effectiveness of hormonal contraceptives Always confirm with your pharmacist or prescriber before making any change.
How serious is the Estradiol and Isotretinoin 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.
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 Isotretinoin 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 (5)
- Product Information: Amnesteem(R) oral capsules, isotretinoin oral capsules. Mylan Pharmaceuticals Inc, Morgantown, WV, 2010. DailyMed
- Product Information: Claravis(TM) oral capsules, isotretinoin oral capsules. Barr Laboratories, Inc, Pomona, NY, 2010. DailyMed
- Product Information: Sotret(R) oral capsules, isotretinoin oral capsules. Ranbaxy Laboratories Inc. Jacksonville, FL, 2010. DailyMed
- Orme M, Back DJ, & Shaw MA: Isotretinoin and contraception. Lancet 1984; 2:752-753. PubMed
- Hendrix CW, Jackson KA, Whitmore E, et al: The effect of isotretinoin on the pharmacokinetics and pharmacodynamics of ethinyl estradiol and norethindrone. Clin Pharmacol Ther 2004; 75:464-75. DOI
Keep reading about Isotretinoin
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.
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