Nickel is a common cause of allergic contact dermatitis. Contact dermatitis has a different allergic mechanism from that which causes severe, immediate allergic reactions (like bee stings or peanuts). Reactions typically occur 24-48 hours after exposure as an itchy rash in the area exposed. Nickel isn’t only in 5 cent coins – it is a common component of most store-bought jewelry, belt buckles, and pant fasteners, among others. This can be especially troublesome to identify for jewelry or other fashion accessories that are not worn daily. The treatment for allergic contact dermatitis is to avoid exposure, soothing lotions (e.g. calamine), topical antihistamine creams, and in more severe reactions, corticosteroid creams. The rash can take two or more weeks to clear.

For more information on the Allergen of the Month feature, see the overview, and check out the previous post on Soy Products, Roaches and Rodents.