No information is available on the clinical use of tirzepatide during breastfeeding. Because tirzepatide is a large peptide molecule with a molecular weight of 4814 Da, the amount in milk is likely to be low and absorption is unlikely because it is probably partially destroyed in the infant's gastrointestinal tract. Until more data become available, tirzepatide should be used with caution during breastfeeding, especially while nursing a newborn or preterm infant.