Fleet Fosfosoda is a tradename that contains several active ingredients in its composition: Dibasic Sodium Phosphate (Very Low Risk) Monobasic Sodium Phosphate (Very Low Risk) Since each active ingredient of this product may have a different level of risk for breastfeeding, we establish that of the product with higher risk. For more information (pharmacokinetics, references, ...) tap each active ingredient. Note: The composition of certain tradenames varies in each country. Please, make sure this is the composition of the tradename you are looking for..