Updated April 08, 2015.
Written or reviewed by a board-certified physician. See About.com's Medical Review Board.
Eczema is a skin rash that is itchy and red, dry and scaly, and may be accompanied by blisters surrounded by red or discolored areas due to scratching of the affected areas. It is most common in children under age five and appears most frequently around the knees, elbows, cheeks, scalp, wrists, ankles, and extremities. It is also called atopic dermatitis.
Scratching the affected area is a common challenge for many people with eczema, especially children.
The intense itchiness and scratching can cause oozing and infection. Scratching can also thicken and scar the skin over time. If untreated, the rash can be unsightly and be socially difficult.
Eczema may be aggravated by heat, skin irritants such as wool clothing; chemicals or perfumes in soap, lotion or detergents; dry skin; and stress.
Who gets eczema?
The tendency to develop eczema appears to be inherited, so if close family members have had eczema, asthma, or food allergies, a child may be more inclined to have eczema as well.
Eczema occurs most commonly in children. Some 10% to 20% of children will develop eczema worldwide, with about half of those being diagnosed before the age of one. Most children with eczema will either completely outgrow their symptoms or find that their symptoms improve significantly by the time they reach adulthood. About 10% of eczema cases occur for the first time in adolescents or adults.
Many young children with eczema have food allergies -- often to egg or nuts.
Why do people develop eczema?
As mentioned above, eczema has a genetic component: children born into families with a history of asthma, hay fever, eczema, food allergies, or other allergic disorders are more likely to develop eczema.
Other triggers for eczema include animal dander, dust mites, sweating or contact with skin irritants such as wool or soaps.
About one-third of people with eczema are responsive to a food trigger. Eczema may make allergy testing difficult. It can make skin testing almost impossible. (In these cases, RAST tests may be useful). Food allergens can sometimes cause eczema to worsen or "flare up." In people with eczema and food allergies, strictly avoiding food allergens may help reduce or, occasionally, eliminate symptoms.
The most common food triggers for eczema are eggs, milk, peanuts, soy, and wheat. Among these, eggs are strongly associated with eczema. Because of the high number of eczema patients who have food allergies, studies recommend that food allergy screening be a part of the medical evaluation for anyone newly diagnosed, especially children.
How can eczema be managed?
Taking good care of the skin, preventing the itch, and avoiding known triggers for eczema are the best ways to treat and prevent its flare-ups. Avoid any known triggers or irritants such as food allergens, emotional stress, or skin irritants such as perfumes or chemicals. Treat skin dryness using lukewarm baths for young children and milk soaps or cleansers. Pat excess water from the skin and apply a liberal amount of moisturizer or emollient (a cream or ointment that seals in moisture). Use cold compresses to decrease the itchiness of the rash.
Keep the skin cool and able to breathe by using cotton clothing or other natural materials (avoid wool) and avoid overdressing, which can overheat the body. Use fragrance-free soaps, shampoos and laundry detergent and avoid fabric softeners.
Sometimes, corticosteroid and other anti-inflammatory creams must be used to treat the rash. Antihistamines may also be recommended to reduce the itchiness. Antibiotics may be recommended if a skin infection occurs.
Can I preventeczema?
Studies have examined whether late introduction of solid foods, breastfeeding, or supplements of probiotics (helpful bacteria that live in the small intestines) can help prevent eczema in high-risk children. While studies have not found a compelling reason for parents to delay introducing solid foods beyond the current American Academy of Pediatrics recommendation of six months, exclusive breastfeeding for four to six months does seem to help. Several studies have shown that probiotic supplements in infants might help prevent eczema, but this research is not considered conclusive. Ask your doctor before giving your infant probiotics.
Living with Eczema and Food Allergies:
Eczema is a major "quality-of-life" disorder for families dealing with it; it can be quite painful and can be distressing for both children and parents.
Allergy testing may determine whether food allergies are a trigger for eczema and can be useful in understanding the source of eczema, prevention, and treatment of it. If you or your child have eczema and are found through testing to be allergic to a food, strictly avoiding that food may help you reduce eczema symptoms.
Families may be disappointed, though, to find that a food allergen-free diet isn't a "magic bullet." Not everyone with food allergies and eczema finds that abstaining from food triggers eliminates or even substantially alleviates their eczema (although many do).
Your allergist can give you guidance about what to expect after your allergy testing and can help you relieve symptoms of eczema through medication and home treatment. Your doctor needs to know if an eczema rash becomes painful, unusually swollen, or accompanied by a fever, since these are all signs of bacterial infection. Keep in mind that eczema tends to be most severe in children under the age of five, and that many families will find that children's symptoms are, if not completely outgrown, far less severe as they grow older.
Joneja JV. The Health Professional’s Guide to Food Allergies and Intolerances.