Tamoxifen: How It Works, What It's Studied For & Safety
Tamoxifen is a selective estrogen receptor modulator FDA-approved for hormone-receptor-positive breast cancer treatment and prevention; used off-label in male HPG-axis protocols. Clinicians consider it for adjuvant and metastatic hormone-receptor-positive breast cancer (FDA-approved). Compounded variants are dispensed by Wells Pharmacy Network only after a clinician evaluation.
Also known as: Nolvadex
How does Tamoxifen work?
Tamoxifen is metabolized to endoxifen, which competitively binds estrogen receptors. It acts as an estrogen antagonist in breast tissue and as a partial agonist in bone and uterine endometrium.
What is Tamoxifen studied for?
- Adjuvant and metastatic hormone-receptor-positive breast cancer (FDA-approved)
- Risk reduction in women at high risk of breast cancer (FDA-approved)
- Off-label gynecomastia management and HPG-axis support in men
How is Tamoxifen taken?
FDA-approved as oral tablets (10 mg, 20 mg). Compounded liquid preparations exist for non-standard dosing.
Is Tamoxifen FDA-approved? Is it safe?
FDA-approved as a finished drug product when prescribed under its labeled indications. Compounded variants on this site are separate from the branded product and are dispensed only when a clinician determines a compounded preparation is appropriate. Boxed warning regarding endometrial cancer, stroke, and pulmonary embolism. Compounded prescription-only preparations are dispensed by Wells Pharmacy Network. Eligibility is decided by a licensed clinician based on intake and labs, not by checkout. Compounded products on this site are not FDA-approved and are not generic equivalents of any branded medication.
In the Regen Therapy catalog
This compound does not currently appear in an active Regen Therapy protocol. Browse the full catalog for adjacent options.
What does the research say about Tamoxifen?
Decades of breast-cancer trial data; off-label male use is clinical-experience-driven.
Citations & further reading
Considering Tamoxifen as part of a protocol?
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