Eczema Versus Psoriasis

Dr. Ryan Sato
Dermatologist with Sato General and Cosmetic Dermatology

Where did you receive your schooling and training?

After graduating Iolani School, I attended Tufts University, where I received my bachelor’s degree. I came home for medical school at University of Hawaii John A. Burns School of Medicine, and then completed my residency in dermatology at University of Buffalo and at Oregon Health & Science University.


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Dr. Ryan Sato

How long have you been in practice?

I completed residency in July 2014 and opened my practice last September.

What interested you in going into dermatology?

I love being in dermatology because it’s such a great mixture of things. I’m able to prescribe medications to help people with either acute or chronic skin conditions. I also get to perform surgery on excise skin cancers and other growths. I get to care for both children and adults.

Lastly, and probably the best part, is that I help people with problems that stare them in the face on a daily basis. Being able to care for these people and take care of their problems come with such a high level of satisfaction from the patients.

Dermatological issues are something the patient can actually see, and when the problem is not going away, it really prompts the patient to come to see me. I like that it can be patient-initiated, and I really enjoy caring for people’s skin.

Can you describe in what ways psoriasis and eczema are alike and what sets them apart?

Psoriasis and eczema are two different skin diseases. Both have a wide scope. Eczema is a general term that most commonly refers to atopic dermatitis, which is an inability of the skin to retain moisture. It creates dry, red, itchy skin. Typically, we think of children as having atopic dermatitis, but it can continue through adulthood or even appear in adulthood. Because eczema is a general term, it can refer to a number of other diseases, like nummular dermatitis, which typically occur in older individuals. Or an allergic contact dermatitis, which is a rash that develops with people coming into contact with something they are allergic to, just to name a couple diseases. Again, it’s a very broad term.

Psoriasis is when the body’s own immune system is hyperactive, creating areas of inflammation in the skin. It creates dry and itchy skin, and it typically looks different from eczema, so seeing a dermatologist is important because a trained professional can diagnose the difference between the two.

Would it be correct to say psoriasis has systemic causes, whereas eczema is more skin-based?

Yes. Psoriasis does have a more internal cause because the immune system is causing the inflammation. People with psoriasis can get psoriaticarthritis, where the inflammation can travel into the joints, which can cause permanent joint damage and destruction.

As far as eczema or atopic dermatitis, it is more of a skin-related problem. There is a debate whether eczema has an internal component and whether its cause is food allergies. There may be some small component of that, but a lot of eczema is the skin’s inability to retain moisture. For example, allergy shots and treatments have not been proven helpful for atopic dermatitis.

How does a person acquire psoriasis?

There are a number of factors. There is a genetic component because psoriasis can run in families. As common as it is, we don’t know the exact causes. There likely is an environmental component that triggers psoriasis, because we know that psoriasis either can occur when you’re younger or appear when someone is older, in their 40s to 60s.

What is the treatment for each?

Depending on the case and cause, there are multiple treatments for each. For local or mild disease, we can use topical creams to help decrease the skin’s inflammation. If it’s very severe, we may need to use oral or systemic medications. With psoriasis, there’s a newer subset of medications called biologics. They are systemic medications we use that have revolutionized how we treat very severe psoriasis. Previous systemic medications only could suppress the whole immune system.

As research and treatment have advanced, we now know the exact molecules that play a large role in psoriasis, and these biologics are able to specifically target these molecules.

Light therapy also is another treatment option and can be used in-office.

Is it possible to get rid of eczema or psoriasis, or is it all about managing treatment?

Unfortunately, there’s no magic cure that can make these conditions go away forever.

Fortunately, there are medications with which we can help clear the skin and manage symptoms, and allow people to live their lives normally. Hopefully, one day science will progress enough where we have that medication to make these things go away forever.

Are either of these conditions preventable?

Our understanding from the science that’s available now is that there isn’t anything you can do to prevent yourself from getting psoriasis.

As far as eczema, there is research showing certain steps as a young child or in utero may decrease your risk of getting atopic dermatitis. However, with the information we have now, there are no universal recommendations or specific steps to adopt at this point.

Anything else you’d like to mention?

One of the biggest troubles that patients tell me they have is how differently people act and treat them because of their skin condition. People fear that they could catch these conditions. Psoriasis and eczema are not contagious.

I see and touch people with both of these conditions multiple times per day and I haven’t caught it yet.

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