ā/nas trō/zöl

Brand Name: Arimidex®

• Generic Available

Common Dosage Forms:

  • Tablets: 1 mg

FDA Indications/Dosages:

  • For the adjuvant treatment of postmenopausal women with hormone receptor-positive early breast cancer: 1 mg daily.
  • For the first-line treatment of postmenopausal women with hormone receptor-positive or hormone receptor-unknown locally advanced or metastatic breast cancer: 1 mg daily.
  • For the treatment of advanced breast cancer in postmenopausal women with disease progression following tamoxifen therapy: 1 mg daily.

Monitor: BMD, Lipid Panel

Pharmacology/Pharmacokinetics:

Anastrozole is a selective non-steroidal aromatase inhibitor. Aromatase is responsible for converting androstenedione to estrone in peripheral tissues. This is the primary source of circulating estrogen in postmenopausal women. The growth of some breast cancers rely on the stimulation of estrogen receptors on the tumor by estrogen. Anastrozole is well absorbed orally and absorption is not affected by food. Metabolism occurs via N- dealkylation, hydroxylation, and glucuronidation. Elimination half-life is about 50 hours and steady-state levels are reached in 7 days.

Drug Interactions:

Estrogen and estrogen-containing drugs may inhibit the pharmacological action of anastrozole. Tamoxifen may inhibit the plasma levels of anastrozole.

Contraindications/Precautions:

Use is contraindicated in any patient who has shown a hypersensitivity reaction to the drug or any of its excipients. Anastrozole may cause fetal harm when given to pregnant women. Pregnancy must be excluded before treatment is started. Use is not recommended in premenopausal women. Pregnancy Category D.

Adverse Effects:

The most common adverse effects include vasodilation, nausea, vomiting, asthenia, localized pain, constipation, diarrhea, headache, and flu syndrome. May cause a reduction in bone mineral density because it lowers circulating estrogen levels. May increase total cholesterol levels.

Patient Consultation:

  • Store in a cool, dry place away from sunlight and children.
  • If a dose is missed take it as soon as possible. If it is closer to the time of your next dose than the dose you missed, skip the missed dose and return to your dosing schedule. Do not double doses.
  • Contact a physician if the above side effects are severe or persistent.
  • Notify a physician if marked weakness, drowsiness, pain or swelling of legs, blurred vision, or shortness of breath occur.