Toremifene
Toremifene is a selective estrogen receptor modulator (SERM) used primarily to treat hormone receptor-positive breast cancer in postmenopausal women. As a nonsteroidal triphenylethylene derivative, it binds to estrogen receptors and can exhibit both estrogenic and antiestrogenic effects depending on the target tissue.
Toremifene is an estrogen receptor modulator used to treat breast cancer by blocking estrogen effects in breast tissue.
This medication carries a boxed (black box) warning — the strongest type of FDA warning. Review the full prescribing information before use.
Key facts at a glance
- ATC
- L02BA02
- RxNorm
- 38409
- Generic
- Toremifene
- Class
- atc-l02
- Brands
- Fareston
- Availability
- rx
- Pregnancy
- D
- Lactation
- unsafe
- Routes
- oral
- Forms
- tablet
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Treatment of metastatic breast cancer in postmenopausal women with estrogen receptor-positive tumors. May also be used in the treatment of breast cancer in premenopausal women in certain contexts.
Toremifene binds to estrogen receptors, acting as an estrogen antagonist in breast tissue while potentially having estrogen-like effects in other tissues such as bone and endometrium.
Common side effects include hot flashes, sweating, nausea, and vaginal discharge. May increase risk of endometrial changes and requires regular monitoring. Contraindicated in patients with known hypersensitivity to the drug. Drug interactions may occur with anticoagulants and other medications metabolized by CYP enzymes.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed July 26, 2026. · Read our editorial policy