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trademark for a preparation of tamoxifen, an antiestrogen used for breast cancer.

tamoxifen citrate

Apo-Tamox, Gen-Tamoxifen, Nolvadex, Nolvadex-D, Novo-Tamoxifen, PMS-Tamoxifen, Soltamox, Tamofen

Pharmacologic class: Nonsteroidal antiestrogen

Therapeutic class: Antineoplastic

Pregnancy risk category D

FDA Box Warning

For women with ductal carcinoma in situ or high risk of breast cancer, serious and life-threatening events associated with drug use in riskreduction setting include stroke, pulmonary embolism, and uterine cancer. Some of these events were fatal. Discuss potential benefits versus potential risks of these events with these patients. In women already diagnosed with breast cancer, drug's benefits outweigh risks.


Competes with estrogen receptors in tumor cells for binding to target tissues (such as breast); reduces DNA synthesis and estrogen response


Oral solution: 10 mg/5 ml

Tablets: 10 mg, 20 mg

Tablets (enteric-coated): 20 mg

Indications and dosages

Adjunctive treatment of breast cancer

Adults: 20 to 40 mg P.O. daily for 5 years. Daily dosages of 20 mg may be taken as a single dose; daily dosages above 20 mg should be divided and taken b.i.d. (morning and evening).

To reduce breast cancer incidence in high-risk women; treatment of ductal carcinoma in situ

Adults: 20 mg P.O. daily for 5 years

Off-label uses

• Mastalgia

• Ovulation stimulation


• Hypersensitivity to drug

• Concurrent warfarin use

• Women with a history of deep-vein thrombosis or pulmonary embolism

• Pregnancy or breastfeeding


Use cautiously in:

• decreased bone marrow reserve, leukopenia, thrombocytopenia, cataracts, hyperlipidemia

• females of childbearing age.


• Don't break or crush enteric-coated tablets.

• Know that drug is indicated for reducing breast cancer risk only in high-risk women, defined as those older than age 35 who have at least a 1.67% chance of developing breast cancer over 5 years.

Adverse reactions

CNS: confusion, depression, headache, weakness, fatigue, light-headedness

CV: chest pain, deep-vein thrombosis

EENT: blurred vision, ocular lesion, retinopathy, corneal opacity

GI: nausea, vomiting, abdominal cramps, anorexia

GU: vaginal bleeding, discharge, or dryness; irregular menses; amenorrhea; oligomenorrhea; ovarian cyst; pruritus vulvae; endometrial or uterine cancer

Hematologic: leukopenia, thrombocytopenia

Metabolic: hypercalcemia, fluid retention

Musculoskeletal: bone pain

Respiratory: cough, pulmonary embolism

Skin: skin changes, hair thinning or partial hair loss

Other: altered taste, weight loss, tumor flare, tumor pain, hot flashes, edema


Drug-drug. Aminoglutethimide, estrogens: decreased tamoxifen effects

Antineoplastics: increased risk of thromboembolic events

Bromocriptine: increased tamoxifen blood level

Warfarin: increased anticoagulant effect

Drug-diagnostic tests. Aspartate aminotransferase, bilirubin, calcium, creatinine, hepatic enzymes: increased levels

Platelets, white blood cells: decreased counts

Patient monitoring

• Monitor lipid panel, calcium level, mammography results, and gynecologic exam results.

Watch for signs and symptoms of thromboembolic events, including cerebrovascular accident and pulmonary embolism.

• Monitor menstrual cycle pattern for changes that may signal endometrial or uterine cancer.

Patient teaching

• Tell patient to swallow enteric-coated tablets whole without breaking or crushing.

Instruct patient to immediately report leg or calf pain, swelling, or tenderness; unexpected shortness of breath; sudden chest pain; coughing up blood; new breast lumps; vaginal bleeding; menstrual irregularities; changes in vaginal discharge; pelvic pain or pressure; and vision changes.

• Inform patient that increase in bone or tumor pain usually means drug will be effective. Advise her to discuss pain management with prescriber.

• Stress importance of undergoing regular blood tests, mammograms, and gynecologic exams to identify early signs of serious adverse reactions.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.


A trademark for the drug tamoxifen.
References in periodicals archive ?
(285) Side effects from Nolvadex include hot flashes, night sweats, vaginal dryness, as well as musculoskeletal pain, depression, and hair loss.
Chief executive Tom McKillop, who has always warned 2003 would be a trough year, said the reshaping of AstraZeneca's business was clearly on track with pounds 750 million in US sales of Prilosec, Zestril and Nolvadex replaced in the first half by new products.
AstraZeneca has seen its Zestril drug hit by generic competition since July while Prilosec was affected from early December and Nolvadex will be hit from February.
They summarize in their complaint against Barr and AstraZeneca: "As the seller of the only generic version of tamoxifen available, Barr is able to capture approximately 80 percent of the market by pricing the drug slightly below the price Zeneca charges for Nolvadex. Zeneca is able to maintain 100 percent of the market for tamoxifen because it sells the brand name, Nolvadex, itself, and the generic version to Barr.
The major concern appeared to be not whether chemoprevention with agents like tamoxifen (Nolvadex, Zeneca) for postmenopausal women actually work, but rather for which groups of women they work best, and for how long they should be given.
Under the trade name Nolvadex, manufacturer Zeneca Pharmaceuticals has sold tamoxifen for more than 20 years as a treatment for breast cancer.
A leading maker of cardiovascular and anti-cancer treatments such as Casodex and Zoladex for prostate cancer and Nolvadex for breast cancer, the $8.7 billion drag and agrochemicals firm has enjoyed better than 15 percent average annual operating profit growth since its "de-merger." Nonetheless, the recent fall-off in its share price has led observers wonder whether Zeneca's rise has come to a halt.
United Kingdom-based Zeneca Group PLC is the undisputed leader in the breast cancer business, selling $470 million a year of a controversial treatment drug called Nolvadex. Zeneca also sells a carcinogenic herbicide called acetochlor, whose market is estimated at $300 million annually.
Early detection is your best protection." And those who are found to have breast cancer can turn to ICI's spinoff, Zeneca Pharmaceuticals, for the leading treatment drug for breast cancer, Nolvadex (Zeneca's trade name for tamoxifen citrate), an anti-estrogen drug.
Zeneca manufacturers Nolvadex, a breast cancer treatment drug with annual sales approaching $400 million--the best-selling cancer drug of all time.
Recent FDA approval of tamoxifen citrate (Nolvadex) as an adjunct form of therapy in some breast cancer patients provides a welcome addition to the various forms of therapy currently available to women suffering from this all-too-common disease.
The medications include tamoxifen (Nolvadex, Soltamox) and the aromatase inhibitors anastrozole (Arimidex), exemestane (Aromasin), and letrozole (Femara).