Conjugated Estrogens

What it is and how it works

Mechanism of Action Endogenous estrogens are largely responsible for the development and maintenance of the female reproductive system and secondary sexual characteristics. Although circulating estrogens exist in a dynamic equilibrium of metabolic interconversions, estradiol is the principal intracellular human estrogen and is substantially more potent than its metabolites, estrone and estriol, at the receptor level. The primary source of estrogen in normally cycling adult women is the ovarian follicle, which secretes 70 to 500 mcg of estradiol daily, depending on the phase of the menstrual cycle.

Mechanism class: Estrogen Receptor Agonists

Indications

(conjugated estrogens) vaginal cream is a mixture of estrogens indicated for: • Treatment of Atrophic Vaginitis and Kraurosis Vulvae • Treatment of Moderate to Severe Dyspareunia, a Symptom of Vulvar and Vaginal Atrophy, due to Menopause Treatment of Atrophic Vaginitis and Kraurosis Vulvae Treatment of Moderate to Severe Dyspareunia, a Symptom of Vulvar and Vaginal Atrophy, due to Menopause

Dosage and administration (summary)

Generally, when estrogen is prescribed for a postmenopausal woman with a uterus, a progestin should also be considered to reduce the risk of endometrial cancer . A woman without a uterus does not need a progestin. In some cases, however, hysterectomized women with a history of endometriosis may need a progestin . Use of estrogen-alone, or in combination with a progestin, should be with the lowest effective dose and for the shortest duration consistent with treatment goals and risks for the individual woman. Postmenopausal women should be re-evaluated periodically as clinically appropriate to determine if treatment is still necessary.

Contraindications

vaginal cream is contraindicated in women with any of the following conditions: • Undiagnosed abnormal genital bleeding • Breast cancer or a history of breast cancer • Estrogen-dependent neoplasia • Active DVT, PE, or a history of these conditions • Active arterial thromboembolic disease (for example, stroke and MI), or a history of these conditions • Known anaphylactic reaction or angioedema to PREMARIN • Hepatic impairment or disease • Protein C, protein S or antithrombin deficiency or other k…

Warnings and precautions

• Estrogens increase the risk of gallbladder disease • Discontinue estrogen if severe hypercalcemia, loss of vision, severe hypertriglyceridemia or cholestatic jaundice occurs ( 5.6 , 5.7 , 5.10 , 5.11 ) • Monitor thyroid function in women on thyroid replacement therapy ( 5.12 , 5.21 ) Risks from Systemic Absorption Systemic absorption occurs with the use of PREMARIN vaginal cream. The warnings, precautions, and adverse reactions associated with oral PREMARIN treatment should be taken into account.

Pregnancy

Pregnancy Risk Summary PREMARIN vaginal cream is not indicated for use during pregnancy. There are no data with the use of PREMARIN vaginal cream in pregnant women; however, epidemiologic studies and meta-analyses have not found an increased risk of genital or nongenital birth defects (including cardiac anomalies and limb-reduction defects) followi…

Storage and supply

Storage and Handling Store at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) .

Source: Conjugated Estrogens (Premarin Vaginal) — US FDA prescribing information, 2025-05-30, DailyMed. Summarised and shortened; the full label governs. Iranian registration, indications and labelling may differ.