Home Drug Guide Anastrozole

Drug Guide

Generic Name

Anastrozole

Brand Names Arimidex

Classification

Therapeutic: Hormone therapy / Antineoplastic agent

Pharmacological: Non-steroidal Aromatase Inhibitor

FDA Approved Indications

  • Postmenopausal women with hormone receptor-positive breast cancer as adjuvant therapy.
  • Treatment of advanced or metastatic hormone receptor-positive breast cancer in postmenopausal women.

Mechanism of Action

Anastrozole inhibits aromatase, an enzyme responsible for converting androgens to estrogens, thereby reducing estrogen levels and limiting the growth of estrogen receptor-positive breast cancer cells.

Dosage and Administration

Adult: Typically 1 mg orally once daily. Exact dosing should be tailored based on patient response and tolerance.

Pediatric: Not approved for pediatric use.

Geriatric: No specific dosage adjustment required, but monitor for adverse effects as in adults.

Renal Impairment: No specific adjustment needed; use caution.

Hepatic Impairment: Use with caution; no specific dosage adjustment established.

Pharmacokinetics

Absorption: Well absorbed orally.

Distribution: Widely distributed in body tissues.

Metabolism: Primarily hepatic via hydroxylation and conjugation.

Excretion: Renal and fecal routes.

Half Life: Approximately 40-50 hours.

Contraindications

  • Known hypersensitivity to anastrozole or any component of the formulation.

Precautions

  • Use with caution in severe liver impairment, osteoporosis risk, and cardiovascular disease. Monitor bone mineral density regularly.

Adverse Reactions - Common

  • Hot flashes (Common)
  • Arthralgia (Common)
  • Weakness (Common)
  • Nausea (Common)

Adverse Reactions - Serious

  • Osteoporosis and fractures (Serious)
  • Cardiovascular events (Serious)
  • Thromboembolism (Serious)
  • Severe allergic reactions (Serious)

Drug-Drug Interactions

  • Tamoxifen (potentially antagonistic effect on anastrozole)
  • Estrogen-containing medications

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor bone density, lipid profile, and cardiovascular status regularly. Assess for symptoms of osteoporosis or fractures.

Diagnoses:

  • Risk for osteoporosis
  • Risk for cardiovascular disease

Implementation: Administer once daily; recommend calcium and vitamin D supplementation; encourage weight-bearing exercises.

Evaluation: Evaluate bone density periodically; monitor for signs of cardiovascular issues.

Patient/Family Teaching

  • Take medication exactly as prescribed.
  • Report any joint pain, bone pain, or signs of osteoporosis.
  • Use calcium and vitamin D as recommended.
  • Avoid estrogen-containing products.

Special Considerations

Black Box Warnings:

  • Increased risk of osteoporosis and fractures during therapy.

Genetic Factors: No current specific genetic considerations.

Lab Test Interference: May decrease bone density markers; monitor serum lipid profiles and bone mineral density.

Overdose Management

Signs/Symptoms: No specific overdose symptoms identified, but possible excess hormonal suppression.

Treatment: Supportive care; no specific antidote. Consultation with poison control is recommended.

Storage and Handling

Storage: Store at room temperature between 20°C and 25°C (68°F to 77°F).

Stability: Stable for at least 2 years when stored properly.

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.