Psoriasis

Psoriasis is an immune-mediated disease which affects the skin and joints. It commonly causes red scaly patches to appear on the skin. The scaly patches caused by psoriasis, called psoriatic plaques or lesions, are areas of excessive skin production and inflammation. Skin rapidly accumulates at these sites and takes a silvery-white appearance. Plaques frequently occur on the skin of the elbows and knees, but can affect any area including the scalp and genitals. Psoriasis is not contagious.

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For more information from the American Academy of Dermatology click here.