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Basics of psoriasis.

Psoriasis is an immune-mediated (controlled by the immune system) disease that causes red, scaly patches (called lesions) on the skin. According to the National Psoriasis Foundation®, it affects nearly 7.5 million people in the United States. Men and women are affected equally. It develops most often between the ages of 15 and 35, but can start in younger children.1

The exact cause of psoriasis is unknown, but the immune system and genetics both play a role. In most patients, there is something that triggers psoriasis to flare. When a flare happens, skin cells start to grow abnormally fast, which leaves a buildup of skin cells on the surface. Psoriasis is not infectious and cannot be passed from person to person.

There are several types of psoriasis:

  • Plaque psoriasis – This is the most common form. It appears as raised, red patches that may be covered in silvery white scales (the buildup of dead skin cells). The patches show up most often on the scalp, knees, elbows and lower back. They can be itchy or painful.
  • Guttate psoriasis – This type shows up as small red dots. It may show up in childhood or early adulthood after a strep infection. It affects about 10 percent of patients with psoriasis.
  • Inverse psoriasis – This type shows up as smooth, shiny, red patches in the body folds, like the armpits or behind the knees. Some people with inverse psoriasis also have another type elsewhere on the body.
  • Pustular psoriasis – People with pustular psoriasis get small, white blisters surrounded by red skin. It most often shows up on the hands and feet. While it may look like an infection, it is not infectious or contagious.
  • Erythrodermic psoriasis – This is a rare, severe type of psoriasis that causes a fiery red rash all over the body. This type of psoriasis can be life threatening, so patients who experience a flare need to see a doctor right away.

While psoriasis lesions can show up anywhere on the body, the most common sites are the scalp, face, hands, feet and skin folds (like the armpits, inside of the elbows or behind the knees). It is considered either mild, moderate or severe.

  • Mild covers less than 3 percent of the body
  • Moderate covers between 3 and 10 percent of the body
  • Severe covers more than 10 percent of the body

Your doctor will consider the extent of your psoriasis when deciding the best course of treatment for you. Generally, mild cases are treated with moisturizers along with over-the-counter and prescription creams and shampoos. Moderate and severe cases are usually treated with a combination of topical creams, phototherapy (light therapy), and sometimes biologic medications that work by suppressing the immune system to prevent flares. Biologics are most often prescribed when psoriasis has a significant impact on a patient’s quality of life.

Talk to your doctor or your CVS Specialty CareTeam if you have questions about your psoriasis and treatment.

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1National Psoriasis Foundation® Website. Accessed October 10, 2018.