21 In the index

Estradiol E2

The main and most powerful human estrogen, FDA-approved for menopause treatment, birth control, and gender-affirming care. Decades of research document both its benefits, like easing menopause symptoms and protecting bones, and its risks, including a higher chance of blood clots depending on dose and delivery method.

Also known as 17-beta estradiol, Estrace, beta-Estradiol, 17beta-Estradiol, Oestradiol, Dihydrofolliculin, Aquadiol, Diogynets

Effects Hormonal

Routes Injectable Oral Topical

Legal status Prescription drug

WADA Not listed

3D Molecular Structure of C₁₈H₂₄O₂

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Chemistry

Formula: C18H24O2
Molar mass: 272.4
CAS: 50-28-2
PubChem CID: 5757
IUPAC name: (8R,9S,13S,14S,17S)-13-methyl-6,7,8,9,11,12,14,15,16,17-decahydrocyclopenta[a]phenanthrene-3,17-diol
InChIKey: VOXZDWNPVJITMN-ZBRFXRBCSA-N

Reported dosing

Approved label

What has been reported in the literature and by users. This is a record of what is done, not a recommendation.

Typical dose 0.5-2 mg/day (oral) or 0.025-0.1 mg/day (patch)

Reported range Varies widely by formulation and indication (menopause, hormone therapy, gender-affirming care)

Route Oral, transdermal patch, gel, or injection

Frequency Once or twice daily (oral/patch) to weekly/biweekly (injectable esters)

Duration Chronic/ongoing (as prescribed)

FDA-approved in multiple formulations; dosing is highly individualized and monitored via bloodwork and symptoms.

Where this comes from FDA prescribing information

These figures are recorded for reference and are not a recommendation. Dosing is a decision for you and a clinician.

Variants

Name	Abbr	Route	Notes
Estradiol valerate	EV	Injectable	An injectable estrogen ester.
Estradiol cypionate	EC	Injectable	A longer-acting injectable estrogen ester.