LactMed: Drugs and Lactation DatabaseU.S. National Library of Medicine. A peer-reviewed and fully referenced database of drugs to which breastfeeding mothers may be exposed. Among the data included are maternal and infant levels of drugs, possible effects on breastfed infants and on lactation, and alternate drugs to consider. Data are organized into substance-specific records, which provide a summary of the pertinent reported information and include links to other NLM databases.