Class: Aromatase Inhibitor
Dosage Forms. Tablet: 1 mg
Common FDA Label Indication, Dosing and Titration.
1. Breast cancer, adjuvant, postmenopausal, hormone receptor-positive: 1 mg po daily × 5 y
2. Breast cancer, advanced, postmenopausal, following tamoxifen therapy: 1 mg po daily, until tumor progression
Off-Label Uses.
1. Breast cancer, neoadjuvant, postmenopausal, hormone receptor-positive: 1 mg po daily for 3-6 mo
MOA. Adrenally generated androstenedione is the primary source of estrogen in postmenopausal women and is converted to estrone by aromatase. Anastrozole is a nonsteroidal aromatase inhibitor.
Drug Characteristics: Anastrozole
Medication Safety Issues: Anastrozole
Drug Interactions: Anastrozole
Adverse Reactions: Anastrozole
Efficacy Monitoring Parameters. Decrease in tumor size if used in metastatic or neoadjuvant setting. Absence of tumor recurrence if used in adjuvant setting.
Toxicity Monitoring Parameters. BP, cholesterol panel, BMD panel (serum albumin, calcium and alkaline phosphatase, and phosphate and osteocalcin measurements), dual energy x-ray absorptiometry for monitoring osteoporosis.
Key Patient Counseling Points. Seek medical attention if shortness of breath, swelling, chest pain, vaginal bleeding, blistering rash, rapid weight gain, severe nausea and vomiting, yellowing of the eyes or skin. Take with or without food.
Clinical Pearls. As effective as tamoxifen in treating metastatic breast cancer, but decreased incidence of adverse effects (thromboembolic events and endometrial cancer). Not indicated in premenopausal women.