Dermatitis (eczema) is inflammation of the upper layers of the skin, causing itching, blisters, redness, swelling, and often oozing, scabbing, and scaling.

Dermatitis is a broad term covering many different disorders that all result in a red, itchy rash. The term eczema is sometimes used for dermatitis. Some types of dermatitis affect only specific parts of the body, whereas others can occur anywhere. Some types of dermatitis have a known cause, whereas others do not. However, dermatitis is always the skin's way of reacting to severe dryness, scratching, an irritating substance, or an allergen. Typically, that substance comes in direct contact with the skin, but sometimes the substance is swallowed. In all cases, continuous scratching and rubbing may eventually lead to thickening and hardening of the skin.