What is eczema?
Eczema is a general term for a group of conditions that cause the skin to become inflamed, red, dry, bumpy, and itchy. However, this term is most often used to refer to a condition called atopic dermatitis. In atopic dermatitis, skin barrier function (the "glue" of the skin) is damaged. This loss of barrier function makes the skin more sensitive and more prone to infection and to becoming dry.
How common is eczema?
Eczema is a common skin condition, affecting as many as 15 million Americans. It most often occurs in very young children. Ten percent to 20 percent of all infants have eczema, according to the National Institutes of Health. However, nearly half outgrow the condition or have significant improvement as they get older. Eczema affects males and females equally, and is more common in people who have a personal or family history of asthma and allergies.
What are the symptoms of eczema?
Common symptoms of eczema include:
- Skin redness
- Dry, scaly, or crusted skin that might become thick and leathery from scratching
- Formation of bumps or small, fluid-filled blisters that might ooze when scratched
In adults, eczema most often affects the hands. In children, eczema is more common in "bending" areas such as the insides of the elbows and backs of the knees. In babies, eczema is usually worst on the face, neck, and scalp.
What causes eczema?
The exact cause of eczema is not known. However, it appears to run in families and occurs more often in people who have a personal or family history of asthma, hay fever, and other allergies. This suggests that there is a genetic (hereditary) factor in the development of eczema (runs in the family).
In addition, eczema symptoms tend to flare up or get worse when the person is exposed to certain substances and situations, called triggers. Eczema triggers might include:
- Skin irritants: Irritants are substances that cause burning, itching, or redness. They include harsh soaps, chemicals, perfumes, and skin care products that contain fragrance or alcohol. Some fabrics, such as wool, and tight clothing can also irritate the skin.
- Allergens: Allergens are substances that trigger an allergic reaction, which may include sneezing, itching, watery eyes, and a stuffed or runny nose. Some allergens such as pollens, pet hair, or foods (in rare cases) can also trigger or worsen eczema symptoms.
- Climate and environment: Low humidity (dry air) can cause the skin to become dry and itchy. Heat and high humidity cause sweating, which can make itching worse.
- Stress: Stress has been shown to trigger flare-ups in some people with eczema. In addition, it may be more difficult to avoid scratching irritated skin when under stress.