No information is available on the clinical use of tildrakizumab during breastfeeding. Because tildrakizumab is a large protein molecule with a molecular weight of 147,000 Da, the amount in milk is likely to be very low.[1] It is also likely to be partially destroyed in the infant's gastrointestinal tract and absorption by the infant is probably minimal.[2] Some professional guidelines state that the drug is acceptable to use during breastfeeding.[3] Until more data become available, tildrakizumab should be used with caution during breastfeeding, especially while nursing a newborn or preterm infant. Waiting for at least 2 weeks postpartum to resume therapy may minimize transfer to the infant.[4]