Eczema and psoriasis, while two distinct conditions, are often mistaken for each other. At first glance, the dry rashes of eczema and psoriasis can look similar. However, when you look closer, there are often telltale differences between the similar symptoms of these two conditions. It’s important to identify and diagnose each skin condition correctly to receive the proper treatment.
We asked two experts, Dr. Paul Yamauchi, a cosmetic, medical and surgical dermatologist in private practice at the Dermatology Institute and Skin Care Center in Santa Monica, California and Dr. Benjamin Ungar, director of the Alopecia Center of Excellence and director of the Rosacea & Seborrheic Dermatitis Clinic at Mount Sinai in New York, to outline the similarities and differences to help tell these two conditions apart.
What does eczema look like?
Eczema is the name for a group of inflammatory skin conditions. There are seven different types of eczema. The most common type of eczema is atopic dermatitis. This is the type of eczema that is most often confused with psoriasis.
Atopic dermatitis, often referred to as just eczema, can vary in appearance depending on skin tone. For light to medium skin tones, atopic dermatitis may appear as pink or red rashes with bumps and crust. For medium to dark skin tones, it may look dark brown, gray or purple with dry, small bumps. Eczema can also change in appearance depending on how long you’ve had symptoms.
“Eczema tends to present with red patches of skin, often with ill-defined borders, that can be accompanied by oozing, crusting or mild scaling,” explained Dr. Ungar.
What does psoriasis look like?
Unlike atopic dermatitis that presents without a distinct border around dry patches, psoriasis presents with well-defined patches on the skin. “Psoriasis tends to present with well-demarcated thick red plaques with silvery scales,” said Dr. Ungar.
Psoriasis looks like it has a layer of scaly patches on top of the redness. Scaling or “plaques” can be silvery, white or red. Skin tends to be thicker, raised and more inflamed than with eczema because psoriasis symptoms cause an excess buildup of skin cells that the body can’t shed quickly enough.
Does psoriasis show up on different parts of the body than eczema?
Yes, the location of rashes on the body is often a differentiator between these skin diseases.
“Although psoriasis and eczema can occur on any part of the body, certain body locations tend to be favored for each condition,” said Dr. Yamauchi. “Psoriasis tends to favor the elbows and knees while eczema is more frequent in front of the elbows and behind the knees. Eczema is [also] more common on the face and neck compared to psoriasis.”
Psoriasis, while potentially appearing anywhere on the body, is more likely on the outer edges of the elbows, knees, scalp, palms, lower back, soles of the feet, ears, mouth, eyelids, buttocks or nails.
With eczema, symptoms most often appear in the skin folds or “crooks” of the body, particularly along the creases of the elbows, knees, wrists, neck and ankles. Babies may also get eczema on the chin, cheeks, scalp, chest, arms and legs. Adults are more likely to have symptoms on patches of skin on their faces or hands.
Is psoriasis itchy like eczema?
“Both eczema and psoriasis can cause itchy skin, but eczema may cause an intense itch while psoriasis causes more of a burning or stinging sensation or mild itch,” said Dr. Yamauchi. Indeed while eczema is typically very itchy — especially at night, to the point of disrupting sleep — psoriasis may not cause itchiness at all.
Comparatively, in people with psoriasis, the immune system is overactive in a manner that leads to the growth of too many new skin cells, too fast. These cells pile up on the surface of the skin, causing thick scales or plaques that can be dry, flaky and painful. However, itch is not as common.
What causes eczema vs. psoriasis?
The exact causes of eczema and psoriasis are unknown. However, both conditions are believed to be influenced by a combination of genetic and environmental factors, such as skin injury or weather. People with atopic dermatitis, the most common type of eczema, tend to have overly-reactive immune systems that, when triggered by a substance outside or inside the body, respond by causing inflammation. Researchers have also found that some people with atopic dermatitis have a mutation in the filaggrin gene, which plays an important role in the skin barrier — leaving the skin more vulnerable to dryness, irritants (like soaps, detergents, fragrances and certain fabrics) and allergens (like dust, pet dander and pollen). Stress can also play a significant role in worsening eczema and psoriasis symptoms.
