Nickel Allergy: understanding the allergy and managing it
First described in 1930 by Dr Stephen Rothman, Nickel induced contact dermatitis has dramatically increased over the last decades. Hypersentization to Nickel is now widely spread around the world, since the estimations for the percentage of population suffering from it vary between 8% to 15% for adults (with a much larger proportion of women compared to men) and 8% of children [ 1, 2, 3]. This allergen has then be qualified as "the allergen of the year" in 2008 by the American Society of Contact Dermatitis .
This allergy is induced after exposure to Nickel has reached a threshold value, which is different for each one.
For a long time, the mechanism of Nickel sensitisation has remained uncleared, with various hypothesis to explain some particularities of this allergy. Actually, what made this contact dermatitis quite unexpected is the quickness of the appearance of symptoms. It means other pathways than the one generally described to explain contact dermatitis must be involved, to enable a quick activation of the inflammatory cascade. Recent study published in nature has shown the influence of one specific receptor, called Toll-Like-Receptor 4 (TLR-4) with a structure that enable Nickel to bind this molecule at a specific site and then induce the inflammatory response. It would open the path to the development of new drug to help cope with Nickel allergy 
When you are allergic to Nickel, there are some rules and tips that are very useful to know and to follow. Some of them are well-known, while some other much less.
Here are listed some of them that can help to cope with Nickel allergy.
Where do you find Nickel?
Actually, Nickel is being used in lots of manufacturing products, due to its properties (slow rate of oxidation at room temperature, magnetic, hard and ductile). You can then found it in a lot of alloys of stainless steel, for exemple. So it may be present in jewellery and clothing decorations, metal tools or medical device. Recent reports have showed that Nickel is still widely spread in daily items [6,7,8,9]
Oxidised forms of Nickel are in the form of coloured solid. That make this element one of the pigments used in make-up, specially eyelid cosmetics and brown make-up. 
Food can also be a consequent source of nickel uptake. Nickel-rich food include chocolate, peanuts, beans, broccoli and canned food. 
Smocking can also induce systemic nickel exposure 
What to do
1 - Get a medical diagnose
When a nickel allergy is suspected, the first move should be to get diagnosed by a M.D. Only a physician is able to perform a patch test that will enable to diagnose a nickel allergy with a fair accuracy. The principle of the test is easily understood. The skin of people suspected to have nickel allergy will be exposed to a very large amount of Nickel for 48 hours under controlled exposure condition, and the results will be made by colorimetric and clinical assessments just after removal of the patch and generally 2 days after.
2 - Treat the rashes
A moisturiser with eventually also corticosteroidal topical treatment is often enough to get rid of the rashes. Some systemic drug such as antihistaminic and corticoids can also be used under medical guidance.
3 - Avoid Nickel Exposure
This tip may me easier said than done. It may indeed be tricky to determine the source of nickel exposure. A chemical compound called dimethylglyoxime (DMG) is used in tests to quickly determine if an item contains Nickel. While colourless at a natural state, it turns pink when the DMG molecules combined with Nickel. Some solutions of this compound are commercially available  and are easy to handle.
Use a barrier to protect skin from metal containing item. It can be clothes, or some gloves (but not rubber gloves, inefficient to block metals). It can be clothes, or some gloves. Rubber gloves should be avoided, since they does not prevent metals to penetrate. Some polyurethane coating can be applied on items, but should be renewed when a degradation of the coating is appearing. A coating can also be put on the item to isolate it from skin. Applying nail polish is a common tip. One drawback of this technique is the development of sensitisation to chemicals found in these products, that can also trigger contact dermatitis . Again, the coating should be applied regularly.
Finally, you can use some skincare product to reduce exposure to Nickel. It can occlusive product, such as petroleum jelly, that will form a liquid glove on your skin, or skincare product specifically designed to reduce skin exposure to Nickel 
- 1 - Scopus
- 2 - Nickel hypersensitivity: a clinical review and call to action
- 3 - The epidemiology of contact allergy in the general population: prevalence and main findings
- 4 - American Contact Dermatitis Society
Nickel, Allergen of the year, 2008
- 5 - Nickel allergy tracked to a single receptor : Nature News
Nature - the world's best science and medicine on your desktop
- 6 - The New York Times
- 7 - Reuters | Nickel in early iPad likely triggered allergy in boy
SAN FRANCISCO (Reuters) - Nickel in a first-generation iPad likely triggered an allergic skin reaction in an 11-year-old boy, a case that highlights an increasingly common condition linked to the rapid
- 8 - The New York Times
- 9 - Hide and Seek: Hidden Causes of Nickel Allergy | The Dr. Oz Show
by Audrey Kunin, MD
- 10 - Review of Ophthalmology - Solving the Mystery Of the Itchy Eyelid
The cause of an itchy eyelid can be a diagnostic puzzle, but persistence often uncovers some common culprits.
- 11 - whatallergy.com - good and bad food for a nickel allergy
- 12 - The level of nickel in smoker's blood and urine.
Cent Eur J Public Health. 2004 Dec;12(4):187-9.
- 13 - Nickel Alert™ - easy and accurate test for nickel!
- 14 - Nail cosmetics allergy. DermNet NZ
Nail cosmetics allergy. Authoritative facts about the skin from DermNet New Zealand.
- 15 - Testimony of Katia, allergic to everything - Skintifique blog
Katia is a 28 year old pharmacist, who suffers from multiple allergies, which include allergies to Nickel and Chromium.