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Related to Nolvadex-D: Apo-Tamox

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.

McGraw-Hill Nurse's Drug Handbook, 7th Ed. Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved


(ta-mox-i-fen) ,


(trade name),


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(trade name),


(trade name)


Therapeutic: antineoplastics
Pharmacologic: antiestrogens
Pregnancy Category: D


Adjuvant therapy of breast cancer after surgery and radiation (delays recurrence).Palliative or adjunctive treatment of advanced breast cancer.Prevention of breast cancer in high-risk patients.Treatment of ductal carcinoma in situ following breast surgery and radiation.


Competes with estrogen for binding sites in breast and other tissues.
Reduces DNA synthesis and estrogen response.

Therapeutic effects

Suppression of tumor growth.
Reduced incidence of breast cancer in high-risk patients.


Absorption: Absorbed after oral administration.
Distribution: Widely distributed.
Metabolism and Excretion: Mostly metabolized by the liver. Slowly eliminated in the feces. Minimal amounts excreted in the urine.
Half-life: 7 days.

Time/action profile (tumor response)

PO4–10 wkseveral moseveral wk


Contraindicated in: Hypersensitivity;Concurrent warfarin therapy with history of deep vein thrombosis (patients at high risk for breast cancer only); Obstetric / Lactation: Pregnancy or lactation.
Use Cautiously in: ↓ bone marrow reserve;Women with childbearing potential.

Adverse Reactions/Side Effects

Central nervous system

  • stroke (life-threatening)
  • confusion
  • depression
  • headache
  • weakness

Ear, Eye, Nose, Throat

  • blurred vision


  • thromboembolism (life-threatening)
  • edema


  • nausea (most frequent)
  • vomiting


  • uterine malignancies (life-threatening)
  • vaginal bleeding

Fluid and Electrolyte

  • hypercalcemia


  • leukopenia
  • thrombocytopenia


  • hot flashes (most frequent)


  • bone pain


  • tumor flare


Drug-Drug interaction

Estrogens may ↓ effectiveness of concurrently administered tamoxifen.Blood levels are ↑ by bromocriptine.May ↑ the anticoagulant effect of warfarin.Risk of thromboembolic events is ↑ by concurrent use of other antineoplastics.


Treatment of Breast Cancer
Oral (Adults) 10–20 mg twice daily; doses of 20 mg/day may be taken as a single dose.
Prevention of Breast Cancer/Ductal Carcinoma in situ
Oral (Adults) 20 mg once daily for 5 yr.

Availability (generic available)

Tablets: 10 mg, 20 mg
Enteric-coated tablets: 20 mg

Nursing implications

Nursing assessment

  • Assess for an increase in bone or tumor pain. Confer with health care professional regarding analgesics. This transient pain usually resolves despite continued therapy.
  • Lab Test Considerations: Monitor CBC, platelets, and calcium levels before and during therapy. May cause transient hypercalcemia in patients with metastases to the bone. An estrogen receptor assay should be assessed before initiation of therapy.
    • Monitor serum cholesterol and triglyceride concentrations in patients with pre-existing hyperlipidemia. May cause ↑ concentrations.
    • Monitor hepatic function tests and thyroxine (T4) periodically during therapy. May cause ↑ serum hepatic enzyme and thyroxine concentrations.
    • Gynecologic examinations should be performed regularly; may cause variations in Papanicolaou and vaginal smears.

Potential Nursing Diagnoses

Deficient knowledge, related to medication regimen (Patient/Family Teaching)


  • Oral: Administer with food or fluids if GI irritation becomes a problem. Consult health care professional if patient vomits shortly after administration of medication to determine need for repeat dose.
    • Do not crush, break, chew, or administer an antacid within 1–2 hr of enteric-coated tablet.

Patient/Family Teaching

  • Instruct patient to take medication as directed. If a dose is missed, it should be omitted.
  • If skin lesions are present, inform patient that lesions may temporarily increase in size and number and may have increased erythema.
  • Advise patient to report bone pain to health care professional promptly. This pain may be severe. Analgesics should be ordered to control pain. Inform patient that this may be an indication of the drug’s effectiveness and will resolve over time.
  • Instruct patient to monitor weight weekly. Weight gain or peripheral edema should be reported to health care professional.
  • Advise patient that medication may cause hot flashes. Notify health care professional if these become bothersome.
  • Instruct patient to notify health care professional promptly if pain or swelling of legs, shortness of breath, weakness, sleepiness, confusion, nausea, vomiting, weight gain, dizziness, headache, loss of appetite, or blurred vision occurs. Patient should also report menstrual irregularities, vaginal bleeding, pelvic pain or pressure.
  • This medication may induce ovulation and may have teratogenic properties. Advise patient to use a nonhormonal method of contraception during and for 1 mo after the therapy.

Evaluation/Desired Outcomes

  • Decrease in the size or spread of breast cancer. Observable effects of therapy may not be seen for 4–10 wk after initiation.
Drug Guide, © 2015 Farlex and Partners


A brand name for TAMOXIFEN.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005