Psoriasis is a skin condition which causes red, flaky, crusty patches of skin covered with silvery scales. The condition is not infectious and most people are affected only in small patches on their body.
It affects around 2% of people in the UK. It can start at any age, but most often develops between the ages of 11 and 45.
The severity of psoriasis varies greatly from person to person. For some people it's just a minor irritation, but for others it has a major impact on their quality of life.
Psoriasis is a long-lasting disease (chronic) that can return at any time. There may be times when you have no symptoms or very mild symptoms followed by times when the symptoms are severe.
Read more about the symptoms of psoriasis.
Outlook
There is no cure for psoriasis, but a range of treatments can improve symptoms and the appearance of the affected skin patches.
Find out more about treating psoriasis.
What happens to the skin?
Skin cells have a life cycle. Your body produces new cells in your deepest skin level. These skin cells gradually move up through the layers of your skin until they reach the outermost level. Then they die and flake off. The whole process normally takes around 21 to 28 days.
In psoriasis, this process speeds up and only takes two to six days. As a result, cells that are not fully mature build up rapidly on the surface of the skin, causing red, flaky, crusty patches covered with silvery scales. These patches are easily shed.
Read about the causes of psoriasis.
Psoriasis can occur on any part of the body, but is most common on the elbows, knees, lower back and scalp. It can cause itching and burning.
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Last updated: 28 March 2012
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