No data are available on the medical use of cocaine in nursing mothers. However, because of its chemical nature, high concentrations of cocaine are expected in milk.[1,2] Cocaine and its metabolites are detectable in breastmilk, although data are from random breastmilk screening of mothers who used cocaine recreationally rather than controlled studies. Cocaine breastmilk concentrations have varied over 100-fold in these reports. Newborn infants are extremely sensitive to cocaine because they have not yet developed the enzyme that inactivates it and serious adverse reactions have been reported in a newborn infant exposed to cocaine via breastmilk.
Cocaine should not be used by nursing mothers or smoked (such as with "crack") by anyone in the vicinity of infants because the infants can be exposed by inhaling the smoke.[3,4] Other factors to consider are the possibility of positive urine tests in breastfed infants which might have legal implications, and the possibility of other harmful contaminants in street drugs. A breastfeeding abstinence period of 24 hours has been suggested for women who occasionally use cocaine while breastfeeding, based on the rapid elimination of cocaine by the mother.[5] Some authors have proposed that breastfeeding be discontinued only for those infants who test positive for cocaine exposure.[6]