The most common allergic reaction is the "polymorphic light dermatosis", which occurs due to too much sun, especially on the face, dйcolletage and arms. Responsible for the allergies are mainly UVA rays, which can also penetrate through glass (car windows). Different forms of sun allergy: Polymorphic photodermatosis (PMD): The most common form of sun allergy affects mainly areas of the skin that are not yet used to the sun. These are, for example, neckline, shoulders or neck. Mostly wheals, itchy spots or blisters appear. Responsible for this is the UVA radiation. For prevention, the use of beta carotenes – and even before departure – is recommended. Mallorca Acne: With 10 to 20 percent is rather a rare form of sun allergy, which occurs especially in holidays in the south. It is not a true allergy, but an intolerance. It occurs through reactions between the sun's UV light and ingredients of sunscreen or other personal care products. On the neck, neck, shoulders or back small achene nodules arise. The sunscreen should be free of emulsifiers, the skin free of cosmetics. Photoallergic reactions Many substances react with sunlight to form decomposition products that can cause allergies or skin discoloration, which is called a "photoallergic reaction". These include certain medicines (eg antibiotics), or contact with some plants (celery, parsley, citrus fruits) or perfumes. Tip against sun allergy: Use only sunscreens with high UVA protection factor and possibly take calcium tablets before sunbathing. Antihistamines and cortisone creams (by the doctor) help when the allergy is there. When sunscreen, make sure that instead of a chemical rather a physical sunscreen (mineral filters, micropigments such as titanium dioxide or zinc oxide) is used! In any case avoid the midday sun (12 to 15 o'clock) and change more often in the shade. Relieve the itching provide cooling antihistaminic or over-the-counter cortisone gels.