IGHE and lactose intolerance: CMPA is a complex disorder caused by an aberrant inflammatory immune reaction to CMP, classified as “immediate” (up to 2 h after allergen ingestion, typically IgE-mediated) or “late onset” (up to 48 h, typically non-IgE or mixed type) adverse reactions that are distinct from those related to cow's milk intolerances (i.e., lactose intolerance) (9–12, 14, 18, 28, 45–47).