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Nickel allergy is a common cause of allergic contact dermatitis — an itchy rash that appears where your skin touches a usually harmless substance.
Nickel allergy is often associated with earrings and other jewelry. But nickel can be found in many everyday items, such as coins, zippers, eyeglass frames, cosmetics, detergents, and even some electronics, including cellphones and laptops.
It may take repeated or prolonged exposure to items containing nickel to develop a nickel allergy. Treatments can reduce the symptoms of nickel allergy. Once you develop a nickel allergy, however, you'll always be sensitive to the metal and need to avoid contact.
An allergic reaction (contact dermatitis) usually begins within hours to days after exposure to nickel. The reaction may last as long as 2 to 4 weeks. The reaction tends to occur only where your skin came into contact with nickel, but sometimes may appear in other places on your body.
Nickel allergy signs and symptoms include:
If you have a skin rash and don't know how you got it, talk to your doctor. If you've already been diagnosed with nickel allergy and are sure you're reacting to nickel exposure, use the over-the-counter treatments and home remedies your doctor has previously recommended.
However, if these treatments don't help, call your doctor. If you think the area may have become infected, see your doctor right away. Signs and symptoms that might indicate an infection include:
The exact cause of nickel allergy is unknown. As with other allergies, nickel allergy develops when your immune system views nickel as a harmful, rather than harmless substance. Normally, your immune system only reacts to protect your body against bacteria, viruses or toxic substances.
Once your body has developed a reaction to a particular agent (allergen) — in this case, nickel — your immune system will always be sensitive to it. That means anytime you come into contact with nickel, your immune system will respond and produce an allergic response.
Your immune system's sensitivity to nickel may develop after your first exposure or after repeated or prolonged exposure.
Common items that may expose you to nickel include:
Some extremely sensitive people may be affected by nickel-containing foods. Some foods that contain high amounts of nickel include soy products, peas, canned foods, cocoa powder, clams and cashews.
Certain factors may increase your risk of developing nickel allergy, including:
Working with metal. If you work in an occupation that constantly exposes you to nickel, your risk of developing an allergy may be higher than it is for someone who doesn't work with the metal.
In addition, people who have regular exposure to nickel while doing "wet work" — as a result of either sweat or frequent contact with water — may be more likely to develop nickel allergy. These people may include bartenders, people who work in certain food industries and domestic cleaners.
Other people who may have an increased risk of nickel allergy include metalworkers, tailors and hairdressers.
The best strategy to prevent a nickel allergy from developing is to avoid prolonged exposure to items containing nickel. If you already have a nickel allergy, the best way to prevent an allergic reaction is to avoid contact with the metal.
However, it's not always easy to avoid nickel because it's present in so many products. Home test kits are available to check for nickel in metal items.
The following tips may help you avoid nickel exposure:
Avoid jewelry that contains nickel. Purchase jewelry that's made of materials that aren't likely to cause allergic reactions. Look for jewelry made from such metals as nickel-free stainless steel, surgical-grade stainless steel, titanium, 18-karat yellow gold, or nickel-free yellow gold and sterling silver.
Surgical-grade stainless steel may contain some nickel, but it's generally considered hypoallergenic for most people. Be sure that your earring backings also are made of hypoallergenic materials.
Before getting a piercing, check to be sure the studio uses sterile, nickel-free or surgical-grade stainless steel needles in sealed packages. If the studio uses a piercing gun, check to see if the part that touches the person getting pierced isn't used on other customers. Check that the studio only sells hypoallergenic jewelry and can provide documentation of metal content of the products for sale.
Look for safer substitutes for common nickel-containing items:
If you have to be exposed to nickel at work, creating a barrier between you and the nickel may help. If your hands have to touch nickel, wearing gloves may help.
Try covering buttons, snaps, zippers or tool handles with duct tape or with a clear barrier, such as Nickel Guard. Clear nail polish on jewelry may help, but may have to be reapplied often.
Your doctor can usually diagnose nickel allergy based on your skin's appearance, and a recent exposure to items that may contain nickel.
If the cause of your rash isn't apparent, however, your doctor may recommend a patch test (contact hypersensitivity allergy test). He or she may refer you to an allergy specialist (allergist) or a skin specialist (dermatologist) for this test.
During a patch test, very small quantities of potential allergens (including nickel) are applied to your skin and covered with small patches. The patches remain on your skin for two days before the doctor removes them. If you have a nickel allergy, the skin under the nickel patch will be inflamed when the patch is removed or in the days after removal of the patch.
Because of the low concentrations of allergens used, patch tests are safe even for people with severe allergies.
The first step in treating nickel allergy is avoiding contact with the metal. There's no cure for nickel allergy. Once you develop a sensitivity to nickel, you'll develop a rash (contact dermatitis) whenever you come into contact with the metal.
Your doctor may prescribe one of the following medications to reduce irritation and improve the condition of a rash from a nickel allergy reaction:
This treatment involves exposing your skin to controlled amounts of artificial ultraviolet light. It's generally reserved for people who haven't gotten better with topical or oral steroids. It can take months for phototherapy to have an effect on a nickel allergy reaction.
You may use some of the following treatments at home to treat contact dermatitis due to nickel allergy. If these treatments don't help or the rash worsens, contact your doctor. Home remedies include the following:
Avoid certain over-the-counter ointments, such as antibiotic creams, which may contain ingredients — particularly neomycin — that can worsen an allergic reaction.
You're likely to see your family doctor first if you're experiencing an itchy rash that may be related to nickel allergy. Preparing for your appointment can help you make the most of your time with your doctor.
Questions that you might want to ask your doctor include:
Your doctor is likely to ask you a number of questions: