LactMed This link opens in a new windowResiding within TOXNET, this is a peer-reviewed reference tool to help patients and healthcare professionals answer questions about drugs to which breastfeeding mothers may be exposed, whether prescription, over-the-counter or illicit. Information is focused on the possible effects for lactating mothers and breastfed infants and includes links to related and/or alternate drugs. These detailed articles include references, chemical structure and registry numbers, and drug classification.