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...

