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Drugs and Lactation Database (LactMed) [Internet]. Bethesda (MD): National Library of Medicine (US); 2006-.
CASRN: 112809-51-5
Drug Levels and Effects
Summary of Use during Lactation
No information is available on the use of letrozole during breastfeeding. The manufacturer recommends that breastfeeding be discontinued during letrozole therapy and for 3 weeks after the last dose.
Drug Levels
Maternal Levels. Relevant published information was not found as of the revision date.
Infant Levels. Relevant published information was not found as of the revision date.
Effects in Breastfed Infants
Relevant published information was not found as of the revision date.
Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.
Substance Identification
Substance Name
Letrozole
CAS Registry Number
112809-51-5
Drug Class
- Breast Feeding
- Antineoplastic Agents
- Aromatase Inhibitors
Disclaimer: Information presented in this database is not meant as a substitute for professional judgment. You should consult your healthcare provider for breastfeeding advice related to your particular situation. The U.S. government does not warrant or assume any liability or responsibility for the accuracy or completeness of the information on this Site.
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