Ethinyl Estradiol vs Levonorgestrel: side-by-side comparison
Ethinyl Estradiol (Synthetic estrogen / contraceptive) and Levonorgestrel (Synthetic progestin (emergency contraception)) belong to different therapeutic classes and are rarely substitutes for each other. The comparison is useful when a single patient is weighing both options for adjacent or overlapping needs.
| Property | Ethinyl Estradiol | Levonorgestrel |
|---|---|---|
| Therapeutic class | Synthetic estrogen / contraceptive | Synthetic progestin (emergency contraception) |
| CAS | 57-63-6 | 797-63-7 |
| ATC | G03CA01 | G03AC03 |
| Molecular weight | 296.40 g/mol | 312.5 g/mol |
| Brands with this active ingredient | 1 | 1 |
What they share
Ethinyl Estradiol and Levonorgestrel share the common regulatory framework for prescription active ingredients, bioequivalence standards for generics, and pharmacist oversight. Beyond that, points in common are limited.
Key differences
Ethinyl Estradiol acts by a different mechanism than Levonorgestrel, with indications that barely overlap. Comparing the two is useful when a clinician has mentioned both in the same context or the patient wants to understand why one was prescribed instead of the other.
Mechanisms compared
Ethinyl Estradiol: Ethinyl estradiol binds estrogen receptors and produces estrogenic effects similar to natural estradiol. Levonorgestrel: In emergency contraception, levonorgestrel works primarily by delaying or inhibiting ovulation when taken before the LH surge.
Indications compared
Ethinyl Estradiol: Ethinyl estradiol is approved as the estrogen component of combined hormonal contraceptives for prevention of pregnancy. Levonorgestrel: Levonorgestrel is approved for emergency contraception (single 1.5mg dose), regular oral contraception (combined with ethinylestradiol or as progestin-only), and as the active component of hormonal intrauterine devices f…
Safety profile
Ethinyl Estradiol: Common adverse effects include nausea, breast tenderness, headache, breakthrough bleeding, mood changes and weight changes. Levonorgestrel: Common adverse effects of emergency contraceptive use include nausea, headache, fatigue, dizziness, breast tenderness and menstrual cycle changes.
Frequently asked questions
Is Ethinyl Estradiol better than Levonorgestrel? ▾
Ethinyl Estradiol and Levonorgestrel are not "better or worse" — they treat different things. The sensible question is which fits your specific need.
Can Ethinyl Estradiol and Levonorgestrel be combined? ▾
Whether they can be combined depends on the indications and the interaction profile of each. If both are in a single prescription, the prescriber has weighed it; in self-medication they should never be combined.
Do they have the same side-effect profile? ▾
No — they belong to different classes and have distinct side-effect profiles. Each has its own prescribing information.
Products with Ethinyl Estradiol
Products with Levonorgestrel
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.