It is impossible consider cross allergy as an individual type of allergy. it is probably a specific property. Peculiarity of cross allergy is that organism has a hyper sensibility not just to one allergen, but to some group of allergens which have a similar structure. The surprising thing is that person suffering from allergy to dust can also suffer from allergic reaction on a shrimp. It has a simple answer: similar set of amino acids in composition of shrimp and household dust. The most widespread pairs of allergens are already known to physicians. It is, for example, camomile and banana, pollen and apples. However cross allergy is so insidious that absolutely unexpected for you substance can act as a twin-allergen. Symptoms of cross allergy differ in nothing from common allergic reactions. However, the more person lives with cross allergy, the more twin-allergens are rejected by his organism. The problem becomes global. Therefore in treatment of cross allergy a proper diagnostics and urgent course of treatment are important. Prophylaxis measures of cross allergy directly depend on detection of primary allergen. Subsequent course of actions becomes more and more clear. If some foodstuff acts as allergen it should be excluded from ration, if some cosmetic – throw it out, if sunshine – wear sunglasses and if possible stay on sun as little time as possible. Anyway, only allergist will be able to develop the most effective allergy prophylaxis program measures for you. And therefore do not be too lazy and ask the experienced doctor for help!