Last Updated: September 11, 2017
Eczema is a catchall word for a number of skin conditions that cause a very itchy, red rash.
The most common form of eczema is atopic dermatitis, or AD. People with AD develop an intensely itchy skin rash that tends to come and go over time. It can affect any part of the body, but is most common on the neck, wrists, ankles, hands and the insides of the knees and elbows. Babies and young children young children with AD usually develop a rash on their faces and scalps.
AD isn’t contagious, and it’s usually not dangerous in itself. However, the intense itching makes it very uncomfortable to live with. Scratching the rash only intensifies the inflammation and can also cause complications like skin infections. Over time, scratching can cause thick, discolored patches to form on the skin - a condition called neurodermatitis. In rare cases, severe eczema on the face can cause permanent damage to the eyes. Treating AD early and practicing good skin care is essential to prevent these problems from developing.
AD affects an estimated 17 million people in the United States, including about 10-20 percent of children and 1-3 percent of adults. Most cases appear before age five, and about half continue into adulthood.
No one knows exactly what causes atopic dermatitis, but research suggests that inherited sensitivities of the skin and immune system play a role.
Some experts believe AD is related to other atopic (allergic) conditions like hay fever and asthma. About half of all people with AD eventually develop one of these conditions, and many have close family members with these allergies.
AD “flares” are usually set off by certain triggers that differ from person to person. Many substances in the environment (called irritants) can trigger a rash in susceptible people, including:
Other possible triggers include:
There’s evidence that AD flare-ups can be worsened by allergies, which are sensitivities to environmental substances like foods, pollen, pets, and dust mites. Exposure causes the allergic person’s immune system to respond as it would to a dangerous substance like bacteria. Immune cells rush to the skin and release inflammatory chemicals that cause swelling, itching and redness.
The AD rash varies from person to person, and can even look different on different body parts of the same person. Common signs include:
Atopic dermatitis usually recurs in flare-ups with symptom-free periods in between. These “remissions” can last weeks, months, or even years.
Some eczema flares can be treated at home, but see a doctor if:
AD is usually diagnosed by history and physical examination. There is no definitive test for the condition. Allergy tests (blood tests, scratch tests) are sometimes used to identify potential triggers.
If AD is suspected, your physician may refer you to a dermatologist or allergist for specialized diagnosis and treatment.
At present, there is no cure for atopic dermatitis. The goals of treatment are to relieve discomfort, prevent complications and minimize future flares.
The best thing people with AD can do for their condition is to practice good skin care. Not only does it help prevent flares, it makes all other treatments more effective. Some essential skin care steps:
Mild AD rash sometimes responds to over-the-counter creams and antihistamines like Benadryl. In more severe cases, your doctor may prescribe:
Some people find that exposing the skin to natural sunlight or ultraviolet lamp light helps their AD rash. Unfortunately, ultraviolet radiation also carries serious health risks, including drying and aging of the skin and increased risk for skin cancer. Your doctor can help you decide if light therapy is right for you, and if so, what precautions to take.
Another thing you can do to help manage your AD is to avoid triggers when possible. Try to avoid getting overheated, manage stress, wear loose clothing and choose skin products designed for sensitive skin or labeled “hypoallergenic.”
The good news about AD is that it tends to improve with age and often disappears by the teenage or young adult years. However, about half of all kids with AD continue to have flares into adulthood.
People who had AD as a child have a lifelong tendency toward dry skin and remain more susceptible to skin problems like staph and herpes virus infections. They may also be at increased risk for eye problems like cataracts.
Because atopic dermatitis is probably a genetic condition, there’s no way to prevent it. However, if you do have AD, take these steps to help prevent flares and complications: