Eczema is a chronic inflammatory skin condition that causes itchy, red, dry, and irritated skin. It affects more than 31 million people in the United States, making it one of the most common conditions treated in dermatology.

Eczema can begin in infancy, childhood, or adulthood and may range from mild and occasional to chronic and severe. It commonly appears on the face, hands, arms, elbows, and behind the knees. Symptoms often flare and improve in cycles.

In young children, eczema frequently presents as extremely dry, itchy skin that may become irritated or infected from scratching. In adults, it may first appear in the 20s or later in life — particularly after age 50 — and often follows a pattern of flare-ups and remissions.