Eczema and psoriasis symptoms overlap. Here’s how to tell what’s really causing your dry, itchy skin.
You have patches of dry, itchy, inflamed skin — is it eczema or psoriasis? Eczema (also known as atopic dermatitis) is one of the most prevalent skin diseases in the United States. But psoriasis affects many people, too.
To the untrained eye, these skin concerns can look very much the same. The most widespread symptoms — dry, itchy, scaly patches of skin — may show up in either condition, according to the Cleveland Clinic.
Psoriasis vs Eczema: Causes
“Psoriasis is an autoimmune disease [that results in] an overproduction of skin cells,” Dr. Khetarpal says.
She explains that in normal skin, it takes around 28 days for a cell to mature, travel to the surface of the epidermis, and be shed along with other dead cells.
In people with psoriasis, however, that process speeds up to just a few days. As a result, live cells can accumulate along with dead ones, which can lead to the formation of scaly lesions.
In eczema, the skin isn’t able to retain water as it needs to, which can make the skin dry and itchy, as well as more sensitive to irritants, says Khetarpal.
There may also be an immune component to eczema, says the National Eczema Association (NEA). People with eczema tend to have an overly reactive immune system that, when triggered by a substance outside or inside the body, responds by producing inflammation. This inflammation causes the discolored, itchy, and painful skin symptoms common to eczema.
Psoriasis vs Eczema: Genetics
With psoriasis, “Genetics seems to play a large role,” says Khetarpal. “People with psoriasis often have a family history of psoriasis or psoriatic arthritis.” About 1 in 3 people with psoriasis have a family member who is also affected, according to the Psoriasis and Psoriatic Arthritis Alliance.
Eczema also tends to run in families, suggesting it has a genetic component, too. It’s seen more commonly in people with a personal or family history of asthma, hay fever, or other allergies. “We call it the allergic triad,” says Khetarpal. “Sometimes someone else in the family has one of these conditions, or the patient may have one, two, or even all three of these conditions.”
Psoriasis vs Eczema: Triggers
In both psoriasis and eczema, certain triggers can bring on a flare. While emotional stress is believed to trigger or worsen both psoriasis and eczema, other triggers are more specific to each condition.
Since eczema is a hypersensitivity, environmental factors can cause a flare. According to the NEA, common eczema triggers include:
- Dry skin
- Metals (especially nickel)
- Fabrics (like wool and polyester)
- Household cleaners
- Antibacterial ointment (like neomycin and bacitracin)
- Cigarette smoke
- Drinking alcohol frequently or excessively
- Skin injury
- Dry, cold weather
- Tattoos and piercings
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Psoriasis vs Eczema: Symptoms
Although a patch of psoriasis or eczema may look similar, there are some differences in how these conditions present themselves, says Khetarpal. These include:
Degree of Itchiness People with eczema tend to experience a lot of itchiness, says Khetarpal. “In our younger patients, the itching can wake them up in the middle of the night — it’s incredibly uncomfortable. People with psoriasis can have some itching but usually not to the same degree as eczema,” she explains.
Location on the Body Both eczema and psoriasis can show up anywhere, but they have their favorite areas, says Khetarpal.
Psoriasis commonly causes troubles on the following body parts:
- Front of the knees
- Lower back
- Soles of feet
Eczema can occur on those places as well but more typically will affect the following:
- Insides of the elbows
- Behind the knees
Dry vs Wet Psoriasis tends to appear drier and flakier, whereas eczema can sometimes be oozy with fluid-filled blisters.
Nail Changes It’s very common to see nail changes in someone who has psoriasis, says Khetarpal. These can include tiny dents; white, yellow, or brown discoloration; crumbling nails; or separation of the nail from the finger or toe. None of this is typically true for eczema. “In eczema, usually the nails are completely normal unless there’s eczema around the cuticle,” Khetarpal adds.
Reaction to Skin Injuries When a person with psoriasis has a skin injury, a flare or new lesion can occur in that area, a response known as the Koebner phenomenon. “A sunburn or a vaccine or any kind of trauma can cause psoriasis to appear in that area — that doesn’t happen in eczema,” says Khetarpal.
Age of Onset “We typically see psoriasis beginning in the teens — the average age is 15 to 30 years old, and so it tends to be later in life compared to eczema,” Khetarpal says. Although people who are older can also develop it, eczema most commonly appears in young children, who often outgrow it in a few years.
Psoriasis vs Eczema: Skin of Color
Psoriasis and eczema can look different in people depending on their racial and ethnic backgrounds.
On light skin, both conditions can cause red patches, but “skin of color may not show redness as much. It can look like hyperpigmentation or darker brown patches instead of red scaly patches,” Khetarpal says. Doctors trained to look for redness may misdiagnose both psoriasis and eczema in people of color, leading to a delay in treatment.
Treatments are the same for anyone with any skin color, says Khetarpal.
Psoriasis vs Eczema: Treatments
There is no cure for either psoriasis or eczema, but the right therapies can often keep skin clear.
Many of the same treatments are used for both eczema and psoriasis. A doctor may recommend:
- Topical Cortisone Either an over-the-counter or prescription steroid cream is often a first-line treatment for either psoriasis or eczema to help ease itching and inflammation.
- Immunosuppressive Drugs Medications such as cyclosporine or methotrexate can help control the immune system response, reduce inflammation, and stop the itch-scratch cycle.
- Biologics These medications target the protein behind the inflammation response. They’re usually given by injection or intravenous infusion.
- Prescription Phototherapy Also called light therapy, phototherapy uses a machine to safely expose the skin to a controlled amount of ultraviolet light. It can reduce itching and inflammation and boost the skin’s ability to fight bacteria. The treatment has been shown to improve both psoriasis and eczema, says Khetarpal, but is more effective in psoriasis.
Eczema may also be treated with:
- Other Over-the-Counter Treatments These might include oral antihistamines, Tylenol (acetaminophen), nonsteroidal anti-inflammatory drugs, and coal tar or dandruff shampoos for scalp eczema.
- Other Prescription Topicals Topical calcineurin inhibitors and phosphodiesterase 4 both target the immune system.
- Oral Steroids These can help fight inflammation.
Psoriasis treatment may also include:
- Other Over-the-Counter Topicals Lotions and shampoos with salicylic acid or coal tar are approved by the FDA to soothe or help get rid of psoriasis.
- Other Prescription Topicals Prescription nonsteroidal medications such as vitamin D analogue products, vitamin A, and anthralin may help reduce inflammation and slow down the formation of plaques.
Psoriasis vs Eczema: Self-Care
Liberal use of a thick, nonirritating moisturizer (either a cream, lotion, or ointment) can ease dryness and help restore the skin barrier in both conditions, says Khetarpal.
Avoiding products with dyes and fragrances is important in eczema.
Since sunburn can worsen both psoriasis and eczema, it’s important to wear a broad-spectrum, water-resistant sunscreen with an SPF of 30 or higher when spending time outdoors.
While there isn’t evidence that a specific diet that eliminates items like dairy or sugar can help either condition, you can benefit from drinking alcohol only in moderation, eating a healthy diet, drinking plenty of water, and exercising (which can reduce stress).
Psoriasis vs Eczema: Complications
Any condition that impacts the skin barrier increases the chance of infection. This can happen with either psoriasis or eczema but tends to be more common in eczema. “In eczema, people are scratching more, so it’s common to see the skin superficially infected,” says Khetarpal.
Psoriasis can also lead to more serious complications. About 30 percent of people with psoriasis will develop psoriatic arthritis, a chronic, inflammatory disease of the joints, according to the National Psoriasis Foundation (NPF).
People with psoriasis are also 1.5 to 2 times more likely to develop heart disease than people without the skin condition, says the NPF. “Psoriasis is not just inflammation of the skin; it causes systemic inflammation and can put you at higher risk for cardiovascular conditions, such as heart attack and stroke,” explains Khetarpal.
Article: By Becky UphamMedically Reviewed by Ross Radusky, MD
Psoriasis vs Eczema: Symptoms, Treatments | Everyday Health