52-year-old Wang Feng (a pseudonym) recently a bit annoying, because she as long as a wear presbyopia, the metal frame contact skin began to redden and itch. Ms. Wang suffers from a typical metal allergy caused by contact dermatitis, outpatient clinic, there are many patients due to metal ear pins, watch chains, hair clips, zippers, necklaces and other metal jewelry caused by skin allergies. Many metal jewelry are proportionally mixed with a small amount of nickel, copper, chromium and other allergenic metals, hot sweat, pores, capillary expansion of metal jewelry in a small amount of nickel sulfate through the pores and sebaceous glands penetrate into the body, and with the body of certain proteins, resulting in allergic inflammation of the skin. So as soon as the summer, metal allergy patients will be more, generally more than the spring and fall seasons about 20%. Once the metal allergic dermatitis, the most fundamental and effective way is to isolate the allergen, such as non-metallic rim glasses, non-metallic belt buckle, etc., as little as possible to wear all kinds of metal jewelry.