Anastrozole is an aromatase inhibitor, an anti-cancer medication use for the adjuvant or initial treatment of breast cancer in post-menopausal women. Estrogen causes or increases growth of certain breast cancers. Anastrozole works by blocking aromatase enzyme, which is involved in estrogen production in the body. This leads to decreased tumor size or delayed progression of tumor growth in some women.

Anastrozole dosage: Anastrozole comes as 1 milligram (mg) tablets and is usually taken once a day for cancer. If you’re a woman taking Anastrozole for infertility, your doctor may prescribe 1 mg to 5 mg for up to five days, beginning on the third day of your period. Take this medication by mouth with or without food as directed by your doctor, usually once a day. Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day.