- Eczema is a common skin condition that can cause swelling and thick, scaly skin.
- Psoriasis is less common than eczema and causes a dry, itchy rash with scaly patches of skin.
- Treatment for mild cases of both conditions is similar, but more severe cases require unique care.
Eczema and psoriasis are common inflammatory skin conditions. They can both be itchy and appear on the same parts of the body – to the untrained eye they are easy to confuse.
Treatments for mild and moderate cases of these conditions are similar, but severe cases may require more specific medications.
Here are the causes, symptoms and treatment of eczema and psoriasis and what makes them different.
What is eczema?
Eczema, or atopic dermatitis, is a common skin condition that affects up to 10% of people in the United States.
Its telltale symptoms include a dry, itchy rash that can range from minor patches to severe flare-ups that are intensely itchy and sometimes painful from scratching.
“Eczema is most commonly seen in children — 95% of cases by age 5 — and much less so in adults,” says Anar Mikailov, MD, dermatologist and founder of KP Away.
Eczema is associated with allergic conditions like
, hay fever and food allergies. More than half of children under 13 with eczema will develop these other conditions.
You are more likely to have eczema if you have family members who also have asthma or environmental allergies. Black children tend to develop it more frequently than white or Asian children – 19% versus 16% and 8%, respectively.
The exact cause of eczema is difficult to determine because several factors influence it:
The latest research shows that there is a genetic basis to eczema. Some genetic variations contribute to an impaired skin barrier, which results in skin cells losing moisture and forming spaces between them, causing dry, irritated and itchy skin.
When you have an impaired skin barrier, your skin is more vulnerable to environmental irritants. Your immune system sees these irritants as dangerous and responds with inflammation, which creates itching and a rash.
Eczema symptom flare-ups can be caused by many different environmental irritants. Some of the most common triggers include:
- Housekeeping and bath products
- Cosmetics with artificial fragrances
- dust and pollen
- Pet dander
- Cigarette smoke
- Climatic factors – change of seasons or extreme weather conditions
Other factors that can increase the risk of developing eczema include where you live. This is more common if you live:
- In a city
- In a high-income country like the United States
- In cold and wet weather
High levels of stress impact the immune system and the skin and increase the inflammatory response that causes eczema.
The main symptom of eczema is itching, which can be very intense and often gets worse at night.
“The itching starts before the rash and appears in symmetrical areas of your body. In children, a symmetrical itchy rash occurs near the elbows, knees, around the eyes, forehead, and nose,” explains Mikailov.
Eczema can also cause:
- A discolored rash – on light colored skin it will be red, on darker skin it may look dark brown, purple or gray
- Thickened, scaly skin due to frequent scratching
- Weeping or crusted areas of skin
“Treatment of mild eczema starts with avoiding environmental triggers, frequent applications of appropriate moisturizers, and topical anti-inflammatory medications. In severe cases, oral medications and injections can be very effective, with quick results. within days to weeks,” says Jeffrey Hsu, MD, dermatologist and founder of Oak Dermatology.
Hsu says that while often effective, these drugs don’t cure – eczema is a chronic condition and occasional flare-ups are to be expected if not properly managed by a dermatologist.
What is psoriasis?
Psoriasis causes a dry, itchy rash characterized by scaly patches of skin. It is quite common, affecting about 3% of adults in the United States, or almost eight million people.
Psoriasis is a chronic, incurable disease that tends to have intermittent flare-ups with worsening symptoms.
“Unlike eczema, psoriasis can be seen in childhood as often as in adulthood and affects men and women equally,” says Mikailov.
Psoriasis is an autoimmune disease – the body’s defense system sees normal, healthy cells as dangerous and releases antibodies to attack them – so the cause of psoriasis is a mechanism similar to other autoimmune diseases such as rheumatoid arthritis, lupus and Hashimoto’s thyroiditis.
In psoriasis, T cells from the immune system attack healthy skin cells. This causes the body to accelerate the creation of new skin cells – these new cells accumulate on the surface of the skin, creating the distinctive scaly appearance of psoriasis.
Psoriasis tends to run in families and has common triggers, both for its first incidence and its flare-ups once established. Common triggers include:
Psoriasis can affect people in different ways. Minor cases may be just a few patches of scaly skin, while some cases may affect large areas of the body. The most common places where psoriasis appears are the scalp and face, elbows, knees, feet, and lower back.
In addition to a scaly rash, symptoms of psoriasis include:
- Dry, cracked skin that may itch and bleed when scratched
- Pitted or cracked nails
- Burning or painful skin
- Articular pain
About one in four people with psoriasis will develop a condition called psoriatic arthritis, which usually occurs years after psoriasis begins on the skin. Psoriatic arthritis shares similarities with rheumatoid arthritis – both cause joint pain, swelling and, in some cases, joint deformity.
People with psoriasis are more likely to develop other conditions such as:
“The treatment of psoriasis involves corticosteroid creams,
cream, phototherapy and sometimes injection or ingested medication. Fortunately, thanks to new drugs, psoriasis can be essentially cured, ”says Mikailov.
You can expect to see improvement in one to two months with injection medicine. Creams and light therapy can take two to three months for improvement, says Mikailov.
Eczema vs Psoriasis
“These two common conditions can look like to the untrained eye – they both appear to be red, scaly rashes initially, and in mild cases, treatments can be very similar,” says Hsu.
Both conditions are caused by a malfunction of the immune system. In eczema, the immune system is overactive, while in psoriasis, the immune system attacks healthy cells — so in severe cases, the medications for each will be different, Hsu says.
Psoriasis, being an autoimmune disease, has more complications than eczema. “While some cases of eczema can be severe, causing a lot of discomfort and itching, psoriasis tends to have more serious and widespread multisystem consequences, including arthritis,
“, says Hsu.
The main differentiation between eczema and psoriasis is itching: eczema is always itchy, sometimes intensely, but the itching associated with psoriasis is milder and tends to be accompanied by a burning or stinging sensation .
Here are some differences between the two:
Eczema and psoriasis are two common skin conditions that can be difficult to tell apart. However, they can usually be treated the same way with topical medications.
For moderate and severe cases, a qualified dermatologist will be able to differentiate between the two and give you the best treatment recommendations.