Antibacterial glycopeptide, administered via intravenous or intramuscularinjection. Its pharmacokinetic data (high molecular weight, high percentage of plasma protein binding and no oral bioavailability) explain the negligible passage into milk observed (Fraissinet 2017) and the absence of side effects in a 52-day-old infant whose mother was being treated with teicoplanin (Kaplan 2017). Not being absorbed orally, there would be no passage to the infant's plasma from ingested breast milk. It is an antibiotic that is administered, if necessary, to newborns. The possible negativity of cultures in febrile infants whose mothers take antibiotics should be taken into account, as well as the possibility of gastroenteritis due to altered intestinal flora.