Anastrozole is a tablet preparation of the third generation, a powerful aromatase inhibitor. This highly selective non-steroid drug is used in sports to prevent the appearance of gynecomastia and water retention in the body. Used only for long-term steroid courses with high doses of drugs. One of the most popular and effective drugs to prevent the side effects of feminization. Acts much more efficiently than the known Tamoxifen, since it is based on a different principle of action.
Anastrozole is a highly selective non-steroidal aromatase inhibitor that in the body of postmenopausal women turns androstenedione in peripheral tissues to estrone and then to estradiol. The therapeutic effect in patients with breast cancer is achieved by reducing the level of circulating estradiol. In postmenopausal women, anastrozole in a daily dose of 1 mg causes a decrease in the level of estradiol by 80%.
Does not possess progestogen, androgenic and estrogenic activity. The daily dose of up to 10 mg does not affect the secretion of cortisol and aldosterone. No replacement for corticosteroids is required. Anastrozole can cause a decrease in bone mineral density in patients with hormone-positive early breast cancer in postmenopausal women. Anastrazole alone, and also in combination with bisphosphonates does not change the level of lipids in the plasma.
Quickly absorbed, the maximum concentration in the plasma is reached within 2 hours after ingestion on an empty stomach. Food slightly reduces the suction speed. The degree of reduction has no clinically significant effect on the equilibrium concentration of the drug in plasma with a single daily dose. Approximately 90-95% of the equilibrium concentration of anastrozole is achieved after 7 days of taking the drug. Data on the dependence of pharmacokinetic parameters on time and dose are absent. The age of postmenopausal women does not affect the pharmacokinetics. Connection with plasma proteins – 40%.
Anastrozole is excreted slowly from the body. The half-life of plasma is 40-50 hours. Extensively metabolized in postmenopausal women. Unchanged, 10% of the dose is given with urine within 72 hours after admission. Metabolized by N-dealkylation, hydroxylation and glucuronization. The main metabolite of triazole does not have activity. Excretion of metabolites occurs in the urine. Cirrhosis of the liver or impaired renal function does not change the clearance of anastrozole after oral administration.
Indications for use
Adjuvant therapy for early hormone-positive breast cancer in postmenopausal women. Common breast cancer in postmenopausal women.
Adjuvant therapy for early hormone-positive breast cancer in postmenopausal women after tamoxifen therapy for 2-3 years.
Interaction with other drugs
There was no clinically significant interaction with phenazone (antipyrine), cimetidine and other commonly prescribed drugs. There is no information on combined use with other antitumor drugs.
Preparations containing estrogens, reduce the pharmacological effect of anastrozole, and therefore, they should not be administered concomitantly with the drug.
The joint use of tamoxifen with anastrozole may weaken the pharmacological action of tamoxifen.