overview Eczema Eczema is the most common type of dermatitis (inflammation of the skin). Eczema refers to several conditions that share a pattern of changes in the surface of the skin. contact Contact Dermatitis Contact dermatitis is a form of skin inflammation that occurs because the skin has been exposed to a substance that irritates it or that causes an allergic reaction. seborrheic Seborrheic Dermatitis Seborrheic dermatitis is a form of skin inflammation (dermatitis). eczema Eczema Eczema is the most common type of dermatitis (inflammation of the skin). Eczema refers to several conditions that share a pattern of changes in the surface of the skin.