Eczema is a chronic, inflammatory skin condition that occurs as the result of an overactive immune response. There are several types of eczema, but atopic dermatitis is the most common, affecting 15% to 20% of children and 1% to 3% of adults. The most common symptom of eczema is dry, itchy, inflamed skin.

But when is a rash just a rash and when is it eczema? It can be difficult to tell.

Here are a few questions to ask yourself if you’re wondering whether your (or your child’s) rash is eczema.

Question 1: What does the rash look like? The most common form of eczema is atopic dermatitis, and it usually presents as a red, itchy rash (sometimes the itching precedes the rash itself). Skin may be dry, scaly or rough, and small, fluid-filled blisters can be present. The rash may crack, ooze, weep or crust with pus.

The way eczema looks can change over time. Initially, the rash may appear as small fluid-filled blisters that ooze or flake when scratched, and the skin will be very itchy, red and inflamed. As the rash begins to heal, skin grows dry, flaky and scaly and may itch less. Over time, if the rash has been scratched often, skin can grow thick, dark and leathery.

When is it not eczema? If the rash presents as itchy red or pale welts that are smooth to the touch, it’s probably a case of hives (urticaria). If the skin is raised, scaly and silver-colored, it may be psoriasis.

Question 2: When did the rash start? If the rash occurs after exposure to animal dander, hygiene or beauty products, fabrics like wool, or certain metals like nickel, it might be contact dermatitis. This form of eczema usually resolves on its own when the cause is removed, but contact dermatitis is not the same as atopic dermatitis which is a chronic, inflammatory condition.

People with atopic dermatitis can be triggered by the same types of things that cause contact dermatitis, plus many common allergens. Typical triggers for atopic dermatitis include soaps and detergents, cold and dry weather, damp weather, cow’s milk, eggs, peanuts, soya, wheat, wool, dust mites, fur, mold, pollen, hormone changes, stress, sweat, and skin infections.

A skin reaction in the form of contact dermatitis once in a while isn’t a problem for most people—they can simply avoid the trigger. Some people can have atopic dermatitis and contact dermatitis at the same time, and it can be hard to tell which is which. Treatment for both is similar. A dermatologist can help.

When is it not eczema? A rash that appears on adults as raised dots that turn into painful blisters could be shingles. Shingles commonly manifest on the torso and buttocks and may cause skin to burn, tingle, itch or become sensitive. Get treatment early to avoid complications.

Question 3: How old is the patient? Eczema commonly starts in infancy or early childhood (up to age 5). Approximately 13% of children develop eczema (and it’s becoming more and more prevalent), but adults can get it, too. Adult-onset eczema usually happens around age 50.
Children often outgrow eczema, but it can come back in adulthood.

When is it not eczema? Kids can get rashes for a number of reasons. Common rashes in children include scabies, scarlet fever, chicken pox, ringworm and impetigo. Some rashes can be dangerous, such as the ring-shaped rash that develops after a tick bite from Lyme disease, a a rash caused by the bacterial infection cellulitis or a drug allergy. See a doctor for any concerning rash.

Question 4: Where is it located? Eczema shows up in different places depending on how old you are and how long you’ve had it. For babies aged zero to six months, eczema usually appears on the cheeks, forehead, chin and scalp. For babies aged six to twelve months, eczema is commonly seen on the elbows and knees. Toddlers aged two to five often have the rash on their wrists, ankles, hands, or around their mouth as well. These longer-term rashes may have reached the lichenification stage, where skin grows dry and scaly or lined. By age five, the child might only have it on his or her hands, although the feet, behind the ears, and the scalp are also common sites of atopic dermatitis as well as seborrheic dermatitis.

When eczema develops in adults it’s usually on the backs of the knees, in the crooks of the elbows, on the back of the neck, or on the face. The skin will be very dry and scaly. People who have had eczema all their lives may have thick, leathery patches of skin that are darker or lighter than the surrounding skin. These thick patches may itch constantly. Adults may also get dark, thickened, itchy skin encircling their eyes.

When is it not eczema:

In babies, a rash in the diaper area is usually not eczema. In adults, redness around the eyes isn’t necessarily eczema. If you flush easily and have visible blood vessels in the face as well as redness, thick skin, or pimply bumps on your face, it could be rosacea.

The best way to know whether a rash is something to worry about is to consult a board-certified dermatologist. We are experts in skin and can make a proper diagnosis as well as offer treatment options to manage troublesome, uncomfortable, and/or unsightly skin issues. While some babies and children who develop eczema will eventually outgrow it, for some, eczema is a lifelong disease. As dermatologists, we are here to help, offering the best, most advanced treatment options to soothe, heal, and protect your skin.