Abstract Cow‘s milk and hen‘s egg are among the most com-mon triggers of IgE-mediated allergic reactions in childhood. Since not all IgE sensitizations are clini-cally relevant, it is important to conrm or exclude manifest allergy. ereby the burden of an elimina-tion diet will be restricted to only those cases where such a measure is essential. A number of proteins have been identied in cow‘s milk and hen‘s egg as single allergens (Bos d 1–12 in cow‘s milk and
Gal d 1–6 in hen‘s egg). However, measuring IgE to these single allergens does neither predict on clini-cal relevance nor prognosis of the individual allergy. In terms of ascertaining whether cooked hen‘s egg is tolerated, measuring sIgE to ovomucoid (Gal d 1) can be useful. Measuring sIgE to lysozyme (Gal d 4) can be helpful to decide whether lysozyme-treated foodstu s (e.g., cheese) should be avoided. Single allergen determination is not able to answer the question of whether cow‘s milk or hen‘s egg are tol-erated in baked form (e.g., in mu˜ns). If the food-stu s in question are tolerated in baked form, their regular consumption has a favorable e ect on prog-nosis.