The pharmacists and doctors on line can respond better, but Pseudoephedrine (sudafed) is a decongestant, not an antihistamine. Therefore I do not think it has as much drying effects, altho when I take it I seem to experience a mild diuretic effect. In general, II think it is better for bf moms to take a single med remedy (like this one) rather than a multi-symptom one when they can. I also think it makes sense to look at the meds our babies/toddlers take (like pseudoephedrine, chlorpheniramine, brompheniramine, diphenhydramine - ingredients in many OTC kids meds for colds, etc) when deciding what would be safe to take. At least that is what I do. Laurie Wheeler, rnc, mn, ibclc