Action

Reduces serum estradiol levels with no significant effect on adrenocorticoid or aldosterone level; decreases stimulating effect of estrogen on tumor growth

Availability

Tablets: 1 mg

Indications and dosages

➣ Postmenopausal women with hormone receptor-unknown or hormone receptor-positive advanced breast cancer or with advanced breast cancer after tamoxifen therapy; adjuvant treatment for hormone receptor-positive breast cancer

Adults: 1 mg P.O. daily

Contraindications

• Hypersensitivity to drug or its components

• Women of childbearing age

Precautions

Use cautiously in:

• ischemic heart disease

• breastfeeding patients

• children (safety and efficacy not established).

Administration

• Verify that patient isn't pregnant before giving drug.

Adverse reactions

CNS: headache, weakness, dizziness, depression, paresthesia, lethargy

CV: chest pain, peripheral edema, vasodilation, hypertension, thromboembolic disease

EENT: pharyngitis

GI: nausea, vomiting, diarrhea, constipation, abdominal pain, anorexia, dry mouth

GU: vaginal bleeding, leukorrhea, vaginal dryness, pelvic pain

Musculoskeletal: decreased bone mineral density, fractures, bone or back pain, muscle weakness

Respiratory: dyspnea, cough

Skin: rash

Other: food distaste, weight gain, swelling, hot flashes, flulike symptoms, tumor flare hypersensitivity reactions (including anaphylaxis, angioedema, urticaria)

Interactions

Drug-diagnostic tests. Hepatic enzymes, low-density lipoproteins, total cholesterol: increased levels

Patient monitoring

See Monitor patient closely for hypersensitivity reactions.

• Check regularly for signs and symptoms of thromboembolic disease, especially dyspnea and chest pain.

• Monitor for circulatory overload (suggested by peripheral edema, cough, and dyspnea).

• Assess for signs and symptoms of depression. Evaluate patient for suicidal ideation.

• Monitor liver function test results.

Patient teaching

See Instruct patient to immediately notify prescriber if signs and symptoms of hypersensitivity occur (such as itching or swelling of face, lips, or throat).

See Advise patient to immediately report signs and symptoms of thromboembolic disease and circulatory overload.

• Emphasize importance of preventing pregnancy during therapy.

• Tell patient to contact prescriber if she develops signs or symptoms of depression.

• Caution patient to avoid driving and other hazardous activities until she knows how drug affects concentration and alertness.

• Advise patient to minimize GI upset by eating small, frequent servings of food and drinking plenty of fluids.

• Inform patient that she'll undergo regular blood testing during therapy.

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