fludrocortisone acetate - Florinef is trade name-is a potent corticosteroid used for partial replacement therapy for primary and secondary adrenocortical insufficiency in Addison's disease and for the treatment of salt-losing adrenogenital syndrome. My thought would be that if it is being used to replace what mom is not producing from her own adrenals then it is basically no different than a mom replacing something like insulin or thyroid. My second thought is why is the mom being given this? For one of these conditions? PDR says use with caution in nursing mom, safety & effectiveness not established for children, growth and development of infants and children on prolonged corticosteroid therapy should be carefully observed. Hope Tom or Jack or Frank have some more info.