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What Is Psoriasis?

Psoriasis is a common and chronic incurable but treatable skin disorder. Plaque psoriasis is the most common form and appears as elevated plaques of red skin covered with silvery scale that may itch or burn. The involved areas are usually found on the arms, legs, trunk, or scalp but may be found on any part of the skin. The most typical areas are the knees, elbows, and lower back.

Plaque psoriasis on the back.
Plaque psoriasis on the back. Image courtesy of Hon Pak, MD.

Psoriasis is not contagious but can be inherited. Research indicates that it is associated with a widespread defect in the inflammatory process.

Factors such as smoking, sunburn, alcoholism, and HIV infection may enhance the severity and extent of the condition.

A significant percentage of people with psoriasis also have psoriatic arthritis. Individuals with psoriatic arthritis have a destructive inflammation of their joints as well as other arthritic symptoms. Occasionally psoriasis of one clinical type may evolve into another such as pustular psoriasis, erythrodermic psoriasis, or guttate psoriasis. Clinical types of psoriasis include the following:

  • In pustular psoriasis, the red areas on the skin contain small blisters filled with pus.
  • In erythrodermic psoriasis, very extensive and diffuse areas of red and scaling skin are present.
  • In guttate psoriasis, there are many isolated small scaling bumps.
Pustular psoriasis.
Pustular psoriasis. Image courtesy of Hon Pak, MD.

Psoriasis affects children and adults. Men and woman are affected equally.

  • Females develop plaque psoriasis earlier in life than males.
  • The first peak occurrence of plaque psoriasis is in people 16-22 years of age.
  • The second peak is in people 57-60 years of age.

Psoriasis can affect all races. Studies have shown that more people in western European and Scandinavian populations have psoriasis than those in other population groups.

Medically Reviewed by a Doctor on 9/19/2017

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The eMedicineHealth doctors ask about Psoriasis:

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Women with eczema

10 Psoriasis Triggers and Treatments

  1. Stress
  2. Allergies
  3. Alcohol
  4. Cold or Dry Weather
  5. Tattoos
  6. Medications
  7. Infections
  8. Cuts and Bruises
  9. Smoking
  10. Hormones

Read What Your Physician is Reading on Medscape

Psoriasis »

Psoriasis is a chronic, noncontagious, multisystem, inflammatory disorder.

Read More on Medscape Reference »

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