To : Jan Re : Carbamide peroxide Carbamide peroxide is a stabilized formulation of hydrogen peroxide linked to urea. It is primarily used for softening and cleansing the ear canal, it is also now used to whiten teeth and treat oral infections. As such very little is absorbed, and that that is would be rapidly destroyed by tissue catalase, hydroperoxidases, and peroxidases present in all tissues of the body, particularly the gut. It is extremely remote, if even possible, that peroxide would reach the plasma and then human milk... unless large quantities were ingested, such as with massive poisoning. Regards Tom Hale, Ph.D.