Contact dermatitis, otherwise known as contact eczema, is a reaction of the skin to direct contact with an allergen. Most commonly, hypersensitivity occurs when the skin comes into contact with chemicals or sunlight.

Contact dermatitis is divided into four types: allergic, irritant, occupational and phototoxic. Inflammation can be caused by a wide variety of objects, such as jewellery, tanned leather, perfumes, dyes in fabrics and cosmetics and many others.