Breast cancer:

Indications for: Tamoxifen

Treatment of metastatic breast cancer in men and women. Axillary node-positive breast cancer in postmenopausal women after surgery + irradiation. Axillary node-negative breast cancer in women after surgery + irradiation. Reduction in risk of invasive breast cancer in women with ductal carcinoma in situ (DCIS) after surgery + radiation. Reduction in breast cancer incidence in high-risk women.

Adult Dosage:

Treatment: 20–40mg/day; give doses >20mg in divided doses (AM and PM). Reduction of incidence in high-risk women or DCIS: 20mg once daily for 5 years.

Children Dosage:

McCune-Albright Syndrome, precocious puberty: see literature.

Tamoxifen Contraindications:

For risk reduction: concomitant coumarin anticoagulants, history of deep vein thrombosis or pulmonary embolism, planned pregnancy. Pregnancy (Cat.D). Nursing mothers.

Tamoxifen Warnings/Precautions:

See literature. Do gynecological exam at least annually. DCIS and risk reduction: consider increased risk of uterine cancer (endometrial adenocarcinoma, uterine sarcoma) and thrombotic events. Women with advanced disease: discontinue if severe hypercalcemia occurs. Monitor blood, lipids, liver function, for thromboembolism symptoms (eg, leg swelling, unexplained shortness of breath), and for uterine changes/cancer (eg, pelvic pain or pressure); promptly investigate any abnormal vaginal bleeding. Breast cancer treatment: history of thromboembolic events. Premenopausal: use effective non-hormonal contraception during and within 2 months of discontinuing therapy; begin therapy during menses or, if irregular menses, obtain (–) B-hCG pregnancy test first.

Tamoxifen Classification:


Tamoxifen Interactions:

May potentiate oral anticoagulants (see Contraindications). Antagonizes anastrozole (avoid concomitant use); letrozole. Plasma levels reduced by CYP3A4 inducers (eg, rifampin). Cytotoxic drugs increase risk of thrombotic events. Potentiated by bromocriptine.

Adverse Reactions:

Hot flashes, vaginal discharge, altered menses, rash, headache, nausea, cough, edema, fatigue, abdominal cramps, bone and tumor pain (in advanced disease), local disease flare, hypercalcemia, thrombotic events, ovarian cysts, uterine fibroids or cancer (endometrial adenocarcinoma, uterine sarcoma), endometrial or visual changes, jaundice, hypertriglyceridemia, blood dyscrasias, hair loss.


Formerly known under the brand name Nolvadex.

How Supplied:

Contact supplier.