Levonorgestrel vs Ethinyl Estradiol: side-by-side comparison
Levonorgestrel (Synthetic progestin (emergency contraception)) and Ethinyl Estradiol (Synthetic estrogen / contraceptive) 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 | Levonorgestrel | Ethinyl Estradiol |
|---|---|---|
| Therapeutic class | Synthetic progestin (emergency contraception) | Synthetic estrogen / contraceptive |
| CAS | 797-63-7 | 57-63-6 |
| ATC | G03AC03 | G03CA01 |
| Molecular weight | 312.5 g/mol | 296.40 g/mol |
| Brands with this active ingredient | 1 | 1 |
What they share
Levonorgestrel and Ethinyl Estradiol 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
Levonorgestrel acts by a different mechanism than Ethinyl Estradiol, 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
Levonorgestrel: In emergency contraception, levonorgestrel works primarily by delaying or inhibiting ovulation when taken before the LH surge. Ethinyl Estradiol: Ethinyl estradiol binds estrogen receptors and produces estrogenic effects similar to natural estradiol.
Indications compared
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… Ethinyl Estradiol: Ethinyl estradiol is approved as the estrogen component of combined hormonal contraceptives for prevention of pregnancy.
Safety profile
Levonorgestrel: Common adverse effects of emergency contraceptive use include nausea, headache, fatigue, dizziness, breast tenderness and menstrual cycle changes. Ethinyl Estradiol: Common adverse effects include nausea, breast tenderness, headache, breakthrough bleeding, mood changes and weight changes.
Frequently asked questions
Is Levonorgestrel better than Ethinyl Estradiol? ▾
Levonorgestrel and Ethinyl Estradiol are not "better or worse" — they treat different things. The sensible question is which fits your specific need.
Can Levonorgestrel and Ethinyl Estradiol 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 Levonorgestrel
Products with Ethinyl Estradiol
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.