Letrozole
- Atc Codes:L02BG04
- CAS Codes:112809-51-5
- PHARMGKB ID:112809-51-5
Table of contents
- Brand Names
- Chemistry
- Pharmacologic Category
- Mechanism of Action
- Therapeutic Use
- Unlabeled Use
- Pregnancy and Lactation Implications
- Contraindications
- Warnings and Precautions
- Adverse Reactions
- Caution and personalized dose adjustment in patients with the following genotypes
- Other genes that may be involved
- Substrate of
- Inhibits
- Drug Interactions
- Dosage
- Pharmacokinetics and Pharmacodynamics
- Special Considerations
Brand Names
Europe
Austria: Femara, Letrofam, Letrozol; Belgium: Femara; Bulgaria: Femara, Letrofemin, Letrosander; Cyprus: Femara; Czech Republic: Aletro, Arofek, Attozette, Brenea, Britagal, Britapons, Clarzole, Dracenax, Etruzil, Femara, Femtozette, Helzette, Lerana, Lestara, Letroger, Letrozette, Letrozol, Letrozole, Letrozolum, Loosyn, Oncozol, Oralet, Trozara, Trozel; Denmark: Femar, Femara, Letrozol; Estonia: Femara, Femtozette, Letroger, Letrozol, Letrozole, Mionic, Picozette, Trozel; Finland: Femar, Femara, Letrolan; France: Femara; Germany: Femar, Femara, Femtozone, Letrobeta, Letrostad, Letrozac, Letrozol, Letrozomic, Letrozonam, Letrozoter, Letrozozett, Mionic, Petazone, Picozone, Ribotrozol, Terazone, Yoktozone; Greece: Femaplex, Femara, Leoncon, Letropen, Letrozin, Letrozol, Letrozole, Levinox, Linol, Mimor, Religan, Stefaplex; Hungary: Femara; Ireland: Eirfem, Femara, Letrozole; Italy: Femara; Latvia: Letrozole, Lithuania: Femara, Femtozone, Letrozol, Letrozole, Mionic, Picozone, Trozel; Luxembourg: Femara; Malta: Letrozole, Femara; Netherlands: Etruzil, Femara, Letaris, Letrozin, Letrozol; Poland: Aromek, Attozone, Etruzil, Femara, Femtozone, Lametta, Letrozol, Letrozole, Letrozone, Lostar, Picozone; Portugal: Femara, Letrozol; Romania: Estronal, Etruzil, Falvax, Femara, Letralan, Letrozol, Letrozole, Loosyn, Trozara, Trozel, Zotrol; Slovakia: Aletro, Brenea, Etruzil, Femara, Femtozone, Letroger, Letromedac, Letrozac, Letrozol, Letrozole, Letrozolum, Lidiozol, Loosyn, Oralet, Trozel; Slovenia: Femara, Femtozone, Letrozol, Picozone; Spain: Femara, Letrozol, Loxifan; Sweden: Femar, Letralan, Letrozol; UK: Femara.
North America
Canada: Femara; USA: Femara, Letrozole.
Latin America
Argentina: Cendalon, Fecinole, Femara, Kebirzol, Letrozol; Brazil: Femara; Mexico: Femara.
Asia
Japan: Femara.
Drug combinations
Chemistry
Letrozole: C~17~H~11~N~5~. Mw: 285.30. (1) Benzonitrile, 4,4′-(1H-1,2,4-triazol-1-ylmethylene)bis-; (2) 4,4′-(1H-1,2,4-Triazol-1-ylmethylene)dibenzonitrile. CAS-112809-51-5. 20267 (1993).
Pharmacologic Category
Antineoplastic Agents; Endocrine Therapy; Aromatase Inhibitor. (ATC-Code: L02BG04).
Mechanism of action
Nonsteroidal competitive inhibitor of the aromatase enzyme. Inhibits the enzyme and reduces estrogen levels.
Therapeutic use
For use in postmenopausal women in adjuvant treatment of hormone receptor-positive early breast cancer, extended adjuvant treatment of early breast cancer after 5 years of tamoxifen, advanced breast cancer with disease progression following antiestrogen therapy, hormone receptor-positive or hormone receptor unknown, locally-advanced, or metastatic breast cancer.
Pregnancy and lactiation implications
May cause fetal harm. Embryotoxic, fetotoxic, and teratogenic in animals. Use with caution during lactation.
Unlabeled use
Treatment of ovarian (epithelial) cancer, endometrial cancer.
Contraindications
Hypersensitivity to letrozole or any component of the formulation. Women of premenopausal endocrine status. Pregnancy.
Warnings and precautions
Hazardous agent. May cause dizziness, fatigue, and somnolence. May cause decreases in bone mineral density. May increase total serum cholesterol. Use with caution in hepatic impairment. Risk of osteoporosis.