What Is Psoriasis, Exactly? A Dermatologist Explains

Here’s how to tell if your rash could actually be psoriasis—and how to get the right treatment.

Loading the player...

When you think of psoriasis, you may automatically assume that it’s just a cosmetic problem. It’s not. Psoriasis is an autoimmune disease; the most prevalent one in the United States at that. Learn about other common psoriasis myths here.

Of the 7.5 million Americans who suffer from psoriasis—approximately 2.2 percent of the population—about 60 percent report that the condition significantly affects their quality of life.

“Psoriasis does have a profound effect on someone’s quality of life. It can lead to depression and feelings of hopelessness,” says Suzanne Friedler, MD, a dermatologist in New York City. “Patients should realize that there is better hope now than ever before in treatments that can clear your skin and keep it clear for long periods of time.”

What Is Psoriasis, Exactly?

Psoriasis is a chronic disease that develops when a person’s skin cells grow too quickly (they form in a few days rather than weeks) due to faulty signals from the immune system. The body doesn’t shed these cells, so they pile up on the surface of the skin, which causes patches of psoriasis to appear.

“Normal skin cells will mature over about a period of two months and shedding will happen over three months. Psoriasis skin cells can mature in about five days,” says Dr. Friedler.

Symptoms of Psoriasis

The symptoms of psoriasis depend on the type of psoriasis you have. There are five main different types of psoriasis: plaque, guttate, inverse, pustular, and erythrodermic. These different types can appear alone, or with another type.

The most common type is plaque psoriasis. “Psoriasis plaques are often red and have very thick, oyster-like scale on them. This can be uncomfortable and they can also be emotionally debilitating to patients,” says Dr. Friedler.

Signs of plaque psoriasis include:

  • Red, flaky, and sometimes itchy skin
  • Patches that are covered with a silvery-white coating, which dermatologists call scale
  • Itchy patches that thicken when scratched
  • Nail problems—pits in the nails, crumbling nail, nail falls off

The most common locations on the body for psoriasis to appear are elbows, knees, the belly button, the crease of the buttocks, and sometimes the scalp. Psoriasis can also appear in the body folds, like under the arms and in the groin folds, which is called inverse psoriasis.

How to Treat Psoriasis

The first step to getting the appropriate treatment is being able to differentiate psoriasis from other skin conditions, and getting properly diagnosed by a dermatologist. “Psoriasis treatment is different than treatment for other rashes, so getting the correct diagnosis from your dermatologist is important in ascertaining that you get the right therapies,” says Dr. Friedler.

Even though psoriasis can’t be cured, there are plenty of lifestyle adjustments that help psoriasis symptoms—like eating a psoriasis-friendly diet, relieving stress, and avoiding habits that can cause psoriasis flare-ups—and medications available that may not only help clear a patient’s skin (sometimes close to completely), but can also significantly improve their quality of life.

“Psoriasis has had an explosion of new therapies over the last few years and this has been providing great hope for patients who’ve been suffering with psoriasis,” says Dr. Friedler. “These new medication classes have also had a profound effect on patients affected by psoriatic arthritis by helping protect their joints and helping prevent progression of that debilitating disease.”

Learn more about how doctors treat psoriasis.