Conditions InDepth: Eczema

Eczema is another word for dermatitis, which is inflammation of the skin. There are many types of eczema, although the term has incorrectly come to be associated with a specific type of dermatitis called atopic dermatitis. Atopic dermatitis is a chronic, noncontagious condition that causes itchy, inflamed skin. Atopic dermatitis (eczema) most commonly affects the insides of the elbows, the backs of the knees, and the face, but it can affect any area of the body. In rare cases, it may cover most of the body.

Although atopic dermatitis can develop at any age, it is most common in infants and children. More than half of people with atopic dermatitis develop symptoms in the first year of life, and almost all develop symptoms before age 5. The condition often improves in adulthood, but half of those affected as children are affected throughout life.

A Baby With Eczema

Copyright © Nucleus Medical Media, Inc.

In the United States, it is estimated that 28 million people have eczema.

The exact cause of atopic dermatitis is still unknown, but current theories suggest that it is related to an abnormal immune response and genetic factors. Atopic dermatitis is often associated with other hereditary allergic disorders, such as hay fever and asthma.

Flare-ups may be triggered by:

  • Extremes in temperature and climate
  • Emotional stress
  • Skin irritants
  • Airborne and contact allergens
  • Viral, bacterial, and possibly fungal infections of the skin
  • Dry skin


Atopic dermatitis. EBSCO DynaMed Plus website. Available at: . Updated July 3, 2017. Accessed December 21, 2017.
Eczema. Kids Health—Nemours Foundation website. Available at:
...(Click grey area to select URL)
Updated June 2015 . Accessed December 21, 2017.
Eczema. National Eczema Association website. Available at:
...(Click grey area to select URL)
Accessed December 21, 2017.
Eczema and atopic dermatitis. Family Doctor—American Academy of Family Physicians website. Available at: Updated June 2017. Accessed December 20, 2017.
Plötz S, Wiesender M, et al. What is new in atopic dermatitis/eczema? Expert Opin Emerg Drugs. 2014 Dec;19(4):441-58.
Understanding your child’s eczema. National Eczema Association website. Available at: Accessed December 21, 2017.
Last reviewed November 2018 by EBSCO Medical Review Board Michael Woods MD, FAAP

EBSCO Information Services is fully accredited by URAC. URAC is an independent, nonprofit health care accrediting organization dedicated to promoting health care quality through accreditation, certification and commendation.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

To send comments or feedback to our Editorial Team regarding the content please email us at Our Health Library Support team will respond to your email request within 2 business days.