Estradiol (Transdermal)

Generic name:

Estradiol (Transdermal)

Drug class:

Estrogens

Dosage form:

Transdermal patch delivering 0.025 mg/day to 0.1 mg/day estradiol

Route of administration:

Transdermal (topical skin application)

Dose:

• 0.025–0.1 mg/day delivered via patch
• Apply one patch to clean, dry skin twice weekly
• Higher doses (up to 0.2 mg/day) may be used for severe symptoms
• Varies by indication; consult label

Mechanism of action:

Estradiol binds to intracellular estrogen receptors (ERα and ERβ), modulating gene transcription and restoring estrogenic activity in target tissues.

Drug usage cases:

• Treatment of moderate to severe vasomotor symptoms (hot flashes) in postmenopausal women
• Prevention of postmenopausal osteoporosis
• Atrophic vaginitis and vulvar atrophy
• Hypoestrogenism due to hypogonadism, castration, or ovarian failure
• Hormone therapy for transgender women (off-label)
• Primary ovarian insufficiency (off-label)
• Cycle regulation in polycystic ovary syndrome (off-label)

Drug contraindications:

• Known or suspected breast cancer
• Known or suspected estrogen-dependent neoplasia (e.g., endometrial carcinoma)
• Undiagnosed abnormal vaginal bleeding
• Active or history of venous thromboembolism (DVT/PE)
• Active or history of arterial thromboembolic disease (e.g., MI, stroke)
• Severe hepatic impairment or liver disease
• Pregnancy
• Hypersensitivity to estradiol or patch components
• Porphyria

Side effects:

• Headache and migraine
• Nausea and vomiting
• Breast tenderness, enlargement, or pain
• Abdominal cramps and bloating
• Vaginal bleeding or spotting
• Edema and fluid retention
• Weight changes
• Mood changes (depression, irritability, nervousness)
• Acne and oily skin
• Skin irritation or erythema at patch site
• Hypercalcemia
• Hypertension
• Thromboembolic events (e.g., DVT, PE)
• Gallbladder disease
• Hypertriglyceridemia
• Endometrial hyperplasia (in women with intact uterus without progestogen)
• Impaired glucose tolerance
• Changes in libido
• Back pain and leg cramps
• Pruritus

Warnings:

• Increased risk of endometrial cancer in women with uterus if unopposed by progestogen
• Increased risk of cardiovascular events (stroke, myocardial infarction), especially in women ≥60 years
• Thromboembolism risk (DVT, PE); use lowest effective dose for shortest duration
• Monitor for breast cancer and cervical/endometrial pathology with regular exams and mammography
• Increased risk of gallbladder disease
• Monitor blood pressure regularly
• May exacerbate asthma, epilepsy, migraine, systemic lupus erythematosus, porphyria
• May cause fluid retention and worsen heart failure
• Caution in hepatic impairment and hypertriglyceridemia
• May increase risk of ovarian cancer with long-term use

Use during pregnancy or breastfeeding:

Pregnancy: Contraindicated (Pregnancy Category X); may cause fetal harm due to hormonal imbalance. Discontinue if pregnancy occurs.

Breastfeeding: Estradiol is excreted in breast milk and may suppress lactation. Use only if benefits outweigh risks; monitor infant for estrogenic effects.