Inhibitor of BCR-ABL and SRC tyrosine kinase that is used for treatment of several neoplastic diseases. At latest update, relevant published data on excretion into breast milk were not found. Because of high serum protein-binding capacity, excretion into breast milk in significant amount is seemingly unlikely. If continuation of safely breastfeeding is desired without assuming high risk for potentially severe side-effects, elimination of total burden of drug should be kept. For this to happen, it should be wait for 10 half-lives (T ½). It means that 13 days should be waited before resuming breastfeeding. Meanwhile, frequent pump-and-dump is recommended for maintenance of milk production.