Nickel allergy: symptoms, causes and treatment

Nickel allergy is an inflammatory reaction that occurs due to an exaggerated immune system response to this mineral, causing symptoms such as skin irritation and itching.

Nickel, or nickel sulfate, is a mineral that can be found in some accessories and jewelry, such as earrings, necklaces, bracelets or watches, as well as metal utensils that contain nickel in their composition, and some foods, such as bananas, peanuts and chocolate, for example.

Nickel allergy occurs mainly in women during adolescence and adulthood. However, people who work with metals, have piercings or have a family history of allergies can also develop this allergy.

Main symptoms

The main symptoms of nickel allergy are:

• Lumps on the skin;
• Swelling at the site;
• Itching and redness of the skin, which can be very intense;
• Blisters on the skin that contain liquid;
• Burn-like spots on the skin.

Allergy symptoms may appear a few hours or days after exposure to nickel, and may take up to 1 month to disappear. It is important that a dermatologist or allergist is consulted to confirm the diagnosis and initiate the most appropriate treatment.

Online symptom test

To find out if you have an allergy, please select the symptoms you are experiencing:

This test is a tool that serves as a means of guidance only. Therefore, it is not intended to provide a diagnosis and does not replace consultation with an allergist, immunologist or general practitioner.

Main causes

Nickel allergy can occur after consuming food or coming into contact with objects that have nickel in their composition.

1. Foods with nickel

Foods that contain nickel in their composition should be eaten in moderation and avoided during the disease crisis, such as:

• Cocoa and chocolate;
• Dried fruits, such as walnuts, almonds, pistachios, hazelnuts, cashews, Brazil nuts, macadamia nuts;
• Legumes, such as beans, lentils, peas and chickpeas;
• Soy, soy milk, tofu and soy flour;
• Rolled oats, oat flour and cassava flour;
• Seeds, such as chia, sesame, pumpkin, sunflower and alfalfa;
• Canned foods, as nickel can be dissociated from the can and increase the nickel content in the food;
• Fruits, such as banana, passion fruit, avocado, coconut, peach, blackberry, raspberry, figs and goji berries;
• Drinks and vitamin supplements with nickel;
• Fish with a high concentration of nickel, such as tuna, herring, salmon and mackerel;
• Shellfish, such as oysters and canned mussels;
• Onion, garlic, chayote, asparagus, okra and green leafy vegetables.

During food preparation, it is important that utensils with nickel should not be used. Furthermore, acidic foods should not be cooked in stainless steel pans, because acids can lead to the dissociation of nickel from the pan and increase the nickel content of the food.

People who drink tap water should reject the initial flow of tap water in the morning, which should not be drunk or used for cooking, as nickel can be released from the tap overnight.

2. Objects with nickel

The main objects that contain nickel in their composition are:

• Metal accessories such as bra and dress clasps, metal buttons, clips, suspenders, hooks, sandal and watch buckles, rings, earrings, bracelets, chains, medals and necklace clasps;
• Objects for personal use, such as lighters, metal eyeglass rings, keys and key chains, metal pens, thimbles, needles, pins and scissors;
• Metal furniture, such as doorknobs and drawers;
• Office supplies such as typewriters, paper clips, staplers and metal pens;
• Cosmetics, such as blue or green eyeshadow and paints;
• Some kitchen utensils.

It is important to pay attention to the appearance of any symptoms on the skin and, if necessary, suspend the use of these objects.

How to confirm the diagnosis

To confirm whether it is indeed a nickel allergy, it is necessary to take an allergy test prescribed and monitored by an allergist or dermatologist, who can also test other substances and foods to assess whether there are other causes of the dermatitis. See how the allergy test is done.

How the treatment is carried out

Initially, it is important to avoid contact with materials that contain nickel. In the presence of an allergic reaction, a dermatologist or allergist should be consulted so that treatment can be indicated, which can include the use of corticosteroid creams and antihistamines. In more severe cases, the use of daily oral corticosteroids, such as prednisone, may be indicated.

In cases where the use of medication is not sufficient, the doctor may recommend phototherapy.