Using a sunscreen is especially important in the mountains and near the equator, but also at the seaside because water reflects the sun’s rays.” And make sure to reapply sunscreen,” Dauber reminded. After 20 minutes in saltwater, even “waterproof” sunscreens wash off to a large extent. Sometimes even sunscreen-protected skin reacts to sunlight with a burning sensation, itching or painful blisters. This is popularly known as a “sun allergy“. It generally affects areas of skin that have not got accustomed to the sun. Its cause is high UVA radiation. Experts recommend sunscreens that give strong protection against UVA radiation and have as few odiferous constituents – which can cause allergic reactions – as possible. For people prone to a sun allergy, doctors suggest taking cortisone or antihistamines, which are also hay-fever remedies. A curd-cheese poultice and aspirin are effective first aids, Dauer noted. Some companies sell UV test strips and UV dosimeters, which you attach to your skin. They signal when your skin type has absorbed a critical amount of UV radiation. But Reinhold said it was more important to develop a feeling for how much sun your skin can take.
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