Levonorgestrel vs Conjugated Estrogens: side-by-side comparison
Levonorgestrel (Synthetic progestin (emergency contraception)) and Conjugated Estrogens (Hormone replacement therapy (estrogen mixture)) 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 | Conjugated Estrogens |
|---|---|---|
| Therapeutic class | Synthetic progestin (emergency contraception) | Hormone replacement therapy (estrogen mixture) |
| CAS | 797-63-7 | 12126-59-9 |
| ATC | G03AC03 | G03CA57 |
| Molecular weight | 312.5 g/mol | 265-272 g/mol (mixture) |
| Brands with this active ingredient | 1 | 1 |
What they share
Levonorgestrel and Conjugated Estrogens 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 Conjugated Estrogens, 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: En contraception d'urgence, le lévonorgestrel agit principalement en retardant ou en inhibant l'ovulation lorsqu'il est pris avant le pic de LH. Conjugated Estrogens: Les estrogènes conjugués agissent sur les récepteurs des estrogènes de l'ensemble de l'organisme, restaurant la signalisation estrogénique perdue après la ménopause.
Indications compared
Levonorgestrel: Le lévonorgestrel est autorisé en contraception d'urgence (dose unique de 1,5 mg), en contraception orale régulière (associé à l'éthinylestradiol ou en progestatif seul), et comme principe actif des dispositifs intra-uté… Conjugated Estrogens: Les estrogènes conjugués sont autorisés dans les symptômes vasomoteurs modérés à sévères de la ménopause, l'atrophie vulvovaginale liée à la ménopause, la prévention de l'ostéoporose chez la femme ménopausée à risque sig…
Safety profile
Levonorgestrel: Les effets indésirables fréquents de la contraception d'urgence comprennent nausées, céphalées, fatigue, vertiges, tension mammaire et modifications du cycle menstruel. Conjugated Estrogens: Les effets indésirables fréquents comprennent nausées, tension mammaire, rétention hydrique, céphalées et saignements intercurrents.
Questions fréquentes
Is Levonorgestrel better than Conjugated Estrogens? ▾
Levonorgestrel and Conjugated Estrogens are not "better or worse" — they treat different things. The sensible question is which fits your specific need.
Can Levonorgestrel and Conjugated Estrogens 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 Conjugated Estrogens
Les informations publiées sur ce site sont fournies à titre documentaire et pédagogique. Elles ne remplacent pas l'avis d'un professionnel de santé qualifié.