What’s the Difference Between Eczema and Psoriasis?

Psoriasis and eczema are both conditions in which the skin develops red, dry, itchy skin patches—so, how can you tell them apart? “To tell the truth, sometimes, it is really challenging to tell the difference,” says David Rosmarin, M.D., dermatologist and vice chair of education and research for the department of dermatology at Tufts Medical Center in Boston, Massachusetts.

So much so that a primary care doctor may not be able to make the official call. It’s likely they’ll refer you to a dermatologist to diagnose you. “A lot of doctors will send their patients to a dermatologist with a guess, but that guess is often wrong,” says Neil Korman, M.D., Ph.D., clinical director of the Murdough Family Center for Psoriasis at University Hospitals in Cleveland, Ohio.

So, if you aren’t sure if your symptoms are indicative of psoriasis or eczema—or what the difference is anyhow—you’re not alone. However, there are a few things to look for that can help you distinguish between the two. This is important so you can get the best treatment for your condition and care for your skin effectively.

Psoriasis vs. Eczema: The Basics

Psoriasis is a chronic disease where your body develops skin lesions as a result of an overactive immune system. It can be related to a host of other health conditions—including psoriatic arthritis, diabetes and heart disease. On the other hand, eczema typically develops as a reaction to triggers like allergens or chemicals that come into contact with the skin, according to the Cleveland Clinic.

As it turns out, your family history may play a role in deciphering whether your symptoms are related to eczema or psoriasis. “If someone comes from a history where many people in the family have psoriasis, that helps us lean more toward a diagnosis of psoriasis,” explains Rosmarin.

Eczema is more likely to be associated a family history of allergies, hay fever, and asthma, adds Korman.

Age of onset may give doctors an additional clue to which condition a person has. “Eczema most commonly (but not always) happens within the first few years of life, whereas, with psoriasis, a more typical age of onset is in the teens and twenties,” says Rosmarin. While it’s possible to have adult-onset eczema, or a child with psoriasis, those aren’t as typical as the reverse.

And yes, it’s also possible to have both psoriasis and eczema—which is known as PsEma. This is when even a skin biopsy can’t distinguish which condition a patient has. “It’s super-rare,” says Korman. “Though, sometimes,” adds Rosmarin, “we do have to treat patients for both diseases.”

Symptom Similarities and Differences

While both conditions cause skin lesions, there are a few differences in how people experience them:

Itchiness

Korman says that an eczema rash is always itchy. Psoriasis plaques aren’t necessarily. “Some people have psoriasis and aren’t bothered by itchiness at all,” he says.

Oozing

If your skin is oozing or leaking, it may be more indicative of eczema.

Location

“Psoriasis often appears on the elbows and knees, while eczema often appears on the opposite side of the elbows and behind the knees,” says Rosmarin.

However, lesions in certain locations, like the palms of the hands and soles of the feet, are harder to distinguish, explains Rosmarin. That said, “Psoriasis tends to spare the arch of the foot, whereas eczema often involves the foot arch,” he adds.

Your nails can also be a key indicator. “Oftentimes, patients with psoriasis will have pitting, oil spots, or a little splinter in the nail—or separation of the nail plate from the nail bed,” says Rosmarin.

Symmetry

“Psoriasis tends to be symmetric—on the left elbow and the right elbow, the left knee and the right knee,” says Korman. “Eczema is typically not as symmetric.”

Treating and Caring for Psoriasis vs. Eczema

Both psoriasis and eczema may be treated medically using a variety of methods—including topical creams, phototherapy and immunosuppressants. You can work with your dermatologist to create the right treatment plan for you.

With eczema, skincare can be really helpful in managing symptoms. “We recommend minimizing soap use, which dehydrates skin [for people with eczema],” says Rosmarin. “Aim for a nice warm shower or bath—avoid scorching-hot or ice-cold showers. And applying moisturizer is extremely important in helping to repair the skin barrier—the greasier the better, and the more frequently you apply the better.”

“People diagnosed with psoriasis usually go to a topical regimen right away, but “With eczema, sometimes, simply moisturizing can make a big difference,” adds Korman.

Clothing choice can also help eczema. “We recommend that people with eczema wear loose-fitting cotton clothing, which is more breathable than irritating fabrics like wool,” adds Rosmarin.

“And it can help to avoid harsh chemicals, or to wear gloves while washing dishes or cleaning,” says Rosmarin. “We also recommend using fragrance-free products.”

Some people with psoriasis find that following similar skincare tips can help their condition, too—especially moisturizing—so, sticking with a quality skincare routine can’t hurt. But just know that it might not make as much difference for people with psoriasis as is does for those with eczema. Medical treatment will likely also be required.

When to See a Dermatologist

There’s no hard and fast rule for when you should see a doctor for your symptoms. “If you have a rash and it’s bothering you because you’re itchy, or if it’s affecting your life—seeing a dermatologist can help distinguish between eczema and psoriasis and treat it appropriately,” says Rosmarin.

It’s ultimately up to you. “It’s a judgment call,” adds Korman. “All patients are different. When it bothers you enough, that’s when you should call your doctor.”

Like with most symptoms, seeing a medical expert earlier rather than later is definitely a good idea.