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Bookshelf ID: NBK500937PMID: 29999996
NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.
Drugs and Lactation Database (LactMed®) [Internet]. Bethesda (MD): National Institute of Child Health and Human Development; 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. An abstract reported that a relative infant dose of 10.2% was found in nursing mother(s) taking letrozole, who provided 8 milk samples over 24 hours, but other details were not supplied.[1]
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.
References
- 1.
- Monfort A, Jutras M, Martin B, et al. New data on the transfer of untested medication into breast milk. Birth Defects Res. 2021;113:831. Abstract.
Substance Identification
Substance Name
Letrozole
CAS Registry Number
112809-51-5
Drug Class
Breast Feeding
Lactation
Antineoplastic Agents
Aromatase Inhibitors
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