What is psoriasis?

Dr. Gary Goldenberg, MD
Dermatologist (Skin Specialist)

Psoriasis is a skin condition that is genetic and presents with scaly, itchy plaques on the skin. There are many types of psoriasis and 30 percent of patients with psoriasis have arthritis. Both can now be treated with a class of medications known as biologics.

Psoriasis is a common autoimmune disorder that affects the skin. It causes itchy or sore patches of thick, red skin with white or silver patches of dead skin, referred to as scales (don’t worry, it doesn’t mean you’re turning into a fish). Psoriasis can affect any part of the body, but it is most common on your head, elbows, knees, and toes, knees and toes. You can develop psoriasis at any age, but it usually appears between 15 and 35 years of age. It’s important to keep in mind that all cases of psoriasis are not created equal, both in terms of severity and in terms of type. There are five kinds of psoriasis. Plaque psoriasis is the most common, but you can also develop guttate, pustular, inverse, or erythrodermic. Each has its own unique characteristics. Be aware, though: Psoriasis is often confused with atopic dermatitis, a form of eczema.

Dr. Joshua A. Zeichner, MD
Dermatologist (Skin Specialist)

Psoriasis is a chronic, inflammatory skin condition. It is considered an autoimmune disease, where the body is "angry" at itself. We do not totally understand why. Patients develop red, scaly plaques typically on the elbows and knees, but can affect any part of the body. The spots can be itchy and flaky, but are not contagious. There are various treatments that your Dermatologist can prescribe you depending on the severity of your condition.

Dr. Douglas E. Severance, MD
Family Practitioner

Psoriasis is a skin disease that speeds up the growth of cells on the skin. A chronic or long-term disorder, psoriasis happens when the immune system gives out the wrong signals to skin cells. Although psoriasis can resemble other skin conditions, this autoimmune disease is not contagious.

There are five types of psoriasis, but the most common type is plaque psoriasis. Plaque psoriasis looks like thick lesions or red, raised patches that are coated with dead skin cells. The dead skin is called scale and is a silvery white color.  Other types of plaque psoriasis include guttate, inverse, pustular and erythrodermic. Not only can psoriasis be found on any body part--it is also linked with serious health disorders such as depression, heart disease and diabetes.

Psoriasis is a common, lifelong skin condition that manifests as red, itchy patches on the skin. In people without psoriasis, skin cells are formed in the deep layers of skin and slowly rise to the surface and die over about a month. But in individuals with psoriasis, this process occurs much faster, causing dead skin cells to build up on the surface. The result is red, flaky, itchy, irritated skin. Psoriasis often disappears and then flares up again over a lifetime.

This answer provided for NATA by the Southern Connecticut State University Athletic Training Education Program.

Various forms of psoriasis exist but, in general, psoriasis is a chronic skin disorder characterized by periodic flare-ups of sharply defined red plaques, covered by a silvery, flaky surface. In the most common form, called plaque psoriasis, thick red patches appear most often on the elbows, knees, scalp, lower back, buttocks, and belly button. Other areas can also be affected, including nails and body folds.

From The Mind-Beauty Connection: 9 Days to Less Stress, Gorgeous Skin, and a Whole New You by Amy Wechsler.


Dr. Ellen S. Marmur, MD
Dermatologist (Skin Specialist)

This condition is characterized by thick, red plaque with a white, silvery (micaceous) scale on top. It's itchy and painful and can create big fissures on the skin. It tends to be on extensor surfaces, such as the elbows, knees, and scalp. There are several types of psoriasis, and some can be quite severe, affecting the joints and causing something called "psoriatic arthritis." It can also be mild, manifesting itself as one patch of plaque on the body, such as dry, cracked elbows that don't soften no matter how much moisturizer you put on.

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Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

Contrary to popular belief, psoriasis is an autoimmune reaction, not an allergy, that brings about inflammation and excess skin cells. When new skin cells are produced during an immune battle, the old ones die and slough off, leading to the scales and patches. It's most likely to be found on the elbows and knees, and usually on the outside of the joint—unlike eczema, which is often on the soft inside skin.

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Psoriasis is more than a skin problem. Psoriasis is a condition where the immune system gets confused and attacks the body for no good reason, making skin inflamed, red and sore in some places. The attacks cause red plaques to form on the surface of the skin. A plaque is an area of the skin that is raised and is not the color of normal skin.

The immune system army sends messages to the skin telling it to make more skin cells and to make them faster than normal. The skin is working overtime, making more cells than it needs. Normally, the skin replaces its outer layer once a month, but in areas of psoriasis, it only takes a few days. The extra skin cells pile up and cause a flaky buildup of scales. The red patches can feel itchy, or they might be sore.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.