The lack of data regarding infant exposure to drugs of abuse consumed by lactating mothers has becomea major health concern. Investigating psychoactive substances and their metabolites in breastmilk is ananalytical approach to estimate the rate at which drugs of abuse are excreted and how much infantsare exposed to them. In this study, we have developed and validated a GC–MS method using disposablepipette tips for simultaneously extracting ten analytes from breastmilk samples obtained from a milk bankin the city of Ribeir ˜ao Preto, Brazil. All the 67 analyzed samples tested negative for all the analytes. Thisis the first study that has applied disposable pipette extraction to analyze drugs of abuse in breastmilksamples.