Drugs in lactation Source: LactMed

Trastuzumab Emtansine and Breastfeeding

Summary of use during lactation

No information is available on the clinical use of trastuzumab emtansine during breastfeeding. Because trastuzumab is a large protein molecule with a molecular weight of 145,531 Da, the amount in milk is likely to be very low. It is also likely to be partially destroyed in the infant's gastrointestinal tract and absorption by the infant is probably minimal. However, emtansine (DM1) is a small-molecule microtubule inhibitory drug, which might be excreted into milk. The manufacturer recommends that breastfeeding be discontinued during trastuzumab deruxtecan therapy and for 7 months after the last dose.

Drug levels in milk and infant serum

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.

Source: Drugs and Lactation Database (LactMed®), National Institute of Child Health and Human Development, NCBI Bookshelf. Check LactMed for the most recent revision.

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