Common triggers for contact dermatitis include:
Poison ivy, poison oak, and poison sumac
Hair dyes or straighteners
Nickel, a metal found in jewelry and belt buckles
Leather (specifically, chemicals used in tanning leather)
Latex rubber
Citrus fruit, especially the peel
Fragrances in soaps, shampoos, lotions, perfumes, and cosmetics
Some medications you put on your skin