It is composed by bisphosphonates. Most bisphosphonates are acidic compounds that achieve low plasma concentration. Both features make it unlikely excretion into the milk in clinically significant amount. Alendronate has shown very low plasma concentrations (<5 ng / ml). Intestinal absorption of bisphosphonates is very low even during fasting and is considered negligible in the presence of milk due to formation with the calcium of non absorbable compounds. A latest update no published data were found on excretion in the breast milk. Until more data about this drug regarding breastfeeding is available, safer known alternatives (e.g. pamidronate) should be of choice, especially in the neonatal period and in case of prematurity.