Nickel sulfate is considered foreign by the immune system -- much like the body would react to a germ. When one of these foreign substances comes into contact with the skin, the body reacts, causing a rash termed an "allergic contact dermatitis." There are many causes of allergic contact dermatitis but they share clinical similarities in the appearance of the rash. Inflammation leads to itching, redness, rough scaly areas, cracking and perhaps weeping or blistered skin.
Repeat insults result in repeat flare-ups. This explains why the earlobes for instance may only develop an itchy rash periodically when certain high-risk earrings are worn versus continuous daily problems with a wedding ring.
Nickel sulfate is considered foreign by the immune system -- much
like the body would react to a germ. When one of these foreign
substances comes into contact with the skin, the body reacts,
causing a rash termed an "allergic contact dermatitis."...
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Dr. Audrey Kunin answered:Nickel sulfate is considered foreign by the immune system -- much like the body would react to a germ. When one of these foreign substances comes into contact with the skin, the body reacts, causing a rash termed an "allergic contact dermatitis." There are many causes of allergic contact dermatitis but they share clinical similarities in the appearance of the rash. Inflammation leads to itching, redness, rough scaly areas, cracking and perhaps weeping or blistered skin.