All nonsteroidal anti-inflammatory drugs (NSAIDs) and antirheumatic drugs are likely to be distributed into human milk to some extent; whether they are detected is a function of the assay sensitivity. For minimal infant exposure, the ideal drug for lactating women is one which (a) has a short half-life, (b) is found in minimal quantities in human milk and (c) has inactive metabolites which also are present only in small amounts. In order to reduce the quantity of drug presented to the child, the drug should be taken by the mother at the time of breast-feeding with the next feed occurring after a time period equivalent to one half-life of the drug. Using the above-mentioned criteria, the choice of NSAIDs would be between a short half-life propionic acid derivative, with little biotransformation, such as ibuprofen or flurbiprofen. Diclofenac is also suitable. Gold salts and corticosteroids would seem safe to prescribe. However, the infant should be closely monitored if antimalarials are being used by lactating women.