INDICATIONS FOR USE

Estradiol is used in hormone replacement therapy (HRT) for postmenopausal women to treat vasomotor symptoms, vaginal atrophy, and osteoporosis prevention. It may also be used for hypoestrogenism due to primary ovarian insufficiency.

LEVEL OF EVIDENCE

✦✦ : Injections : Off-label / non-FDA-approved therapy with early but compelling human efficacy and safety data.

✦✦✦ : Topical / Transdermal : FDA approved therapy with extensive human efficacy and safety data.

ROUTE OF ADMINISTRATION

• Subcutaneous injection, topical gel, cream, or transdermal patch.

COMMON INITIAL DOSING REGIMENS

• Topical Gel/Cream: Typically 0.5–1.5 mg applied once daily to the inner thighs or arms.

• Transdermal Patch: 0.025–0.1 mg estradiol released daily, replaced once or twice weekly.

MECHANISM OF ACTION

• Estradiol binds to estrogen receptors, regulating gene expression and mimicking endogenous estrogen effects. It alleviates menopausal symptoms by maintaining vaginal epithelium, reducing hot flashes, and supporting bone density.

COMMON SIDE EFFECTS

• Endocrine: Breast tenderness, increased vaginal discharge, or breakthrough bleeding.

• Metabolic: Fluid retention, weight changes, or mild bloating.

• Cardiovascular: Rare risks include venous thromboembolism (VTE) and hypertension.

• Dermatological: Local skin irritation with transdermal patches.

• Rare: Long-term use may increase risks of endometrial hyperplasia or estrogen-dependent cancers.

CONTRAINDICATIONS

• Absolute: Active or history of estrogen-dependent cancer, thromboembolic disorders, or undiagnosed vaginal bleeding.

• Relative: Caution in women with liver dysfunction, gallbladder disease, or significant cardiovascular risk factors.