What Is Atopic Dermatitis?

Atopic dermatitis (AD) is the most common type of eczema, affecting more than 9.6 million children and roughly 16.5 million adults in the United States. It is a chronic skin disorder that can cause the skin to be irritated, inflamed, and itchy.

Read more about atopic dermatitis, its causes, symptoms, and treatment methods.

Definition

In those living with atopic dermatitis, the immune system becomes dysfunctional and overreacts, triggering inflammation that causes damage to the skin barrier. This can result in dry skin, itching, and a rash. Atopic dermatitis is often referred to as the "itch that rashes" because an itchy feeling often precedes the appearance of a rash."

There can be periods when atopic dermatitis is worse. These are called flares or flare-ups. At other times, the skin may improve or be entirely clear, known as remission.

Anyone can get atopic dermatitis at any time, but it often begins in early childhood. The cause of the diseases is unknown, but it is not infectious, meaning it isn't caused by organisms, such as bacteria or viruses, and it can't be spread from person to person.

The Types of Eczema

Although atopic dermatitis is sometimes referred to simply as "eczema," AD is actually one kind of many possible forms of eczema.

"Eczema" is a term used to describe conditions that can cause the skin to become itchy and inflamed. Atopic dermatitis is the most common form of eczema.

It is possible to have more than one form of eczema at one time.

Other types of eczema include:

Contact Dermatitis

This form of dermatitis occurs when the skin comes into contact with something that triggers an allergic reaction. It differs from atopic dermatitis because it is less likely to run in families and less likely to be linked to other conditions relating to allergies, like asthma and hay fever.

Nummular Eczema

Also referred to as discoid eczema, nummular eczema refers to eczema that appears as itchy, circular patches on the skin. The word "nummular" comes from the Latin word meaning coin, as it can look like coins on the skin.

Dyshidrotic Eczema

This form of eczema appears as intensely itchy, small blisters found on the palms of the hands, the edges of the fingers and toes, and the soles of the feet. It is more common in people with other types of eczema.

Seborrheic Dermatitis

This chronic form of eczema can appear on oil-producing areas of the body like the scalp, nose and upper back. It can cause redness and scaling.

Atopic Dermatitis Causes and Risk Factors 

The exact cause of atopic dermatitis is unknown, but researchers suspect a number of risk factors could play a role, including the following:

• Family history: You're more likely to get atopic dermatitis if you have a blood relative with atopic dermatitis, hay fever, food allergies, or asthma.
• Immune system: Researchers believe that parts of the immune system are overactivated in people with atopic dermatitis.

Symptoms of Atopic Dermatitis

The most common form of atopic dermatitis is itchy skin. Other symptoms include:

• Dry skin
• Blisters that ooze or crust
• Rashes
• Raw patches of skin due to scratching
• Redness or inflammation
• Thickened or leathery patches of skin
• Changes to skin color

When to Seek Treatment

You should discuss any symptoms that worry you with a medical professional.

Contact a healthcare provider if:

• Atopic dermatitis doesn't improve with care at home.
• There are signs of infection (pain, fever, redness, and being warm to the touch).
• Symptoms get worse.
• Treatments prescribed aren't working.

A healthcare provider can create a treatment plan to manage symptoms. Treatment options can include medications, skin care, and phototherapy, which uses ultraviolet light to treat symptoms.

A Word From Verywell

Atopic dermatitis is the most common form of eczema. It can cause the skin to be itchy, red, and uncomfortable. The exact cause is unknown, but genetics and the immune system are believed to play a role.

The symptoms of atopic dermatitis can be uncomfortable, but there are treatment options available. If you have any concerns about your health, you should speak with a healthcare provider.

Frequently Asked Questions

How is atopic dermatitis diagnosed?

To diagnose atopic dermatitis, a medical provider will examine the skin, take a medical history, and ask about any symptoms. In some cases, consultation with an allergist-immunologist (a doctor trained to diagnose and treat allergies) or a dermatologist (a specialist in skin, hair, and nails) may be necessary. Some people may also need a skin biopsy (removing cells or skin samples to be examined in a lab).

What is the difference between atopic dermatitis and eczema?

"Eczema" is a term used to describe a number of conditions that can cause itchy, inflamed skin. There are many types of eczema. Atopic dermatitis is one type of eczema and is the most common.