Psoriasis Explained

What is Psoriasis?

Psoriasis is a chronic condition that causes scaly patches to develop on the skin. These patches are raised and red, with silvery scales and a distinct border between the patch and normal skin. They occur when skin cells grow abnormally quickly. Although the reason this happens is not well understood, it is thought to involve a problem with the immune system.

The most common type of psoriasis, called plaque psoriasis, usually begins as one or more small patches on the scalp, elbows, knees, back or buttocks. These patches may clear up, remain, or grow together to form larger patches. Some people have only one or two small patches, while others have patches that cover large areas of the body. There are often no other symptoms, although thick patches or patches on the palms, the soles or the skinfolds of the genitals may itch or hurt. Many people with plaque psoriasis also have thickened nails.

Psoriasis is a lifelong disease that gets better or worse in certain circumstances. Exposure to bright sunlight often reduces symptoms, and some people may go for years without occurrences. On the other hand, psoriasis may flare up for no apparent reason, or as a result of stress, minor skin injuries, infections or certain drugs.

Who Gets Psoriasis?

Psoriasis affects between 2% and 4% of white Canadians and is somewhat less common among Canadians of African, Asian or native descent. It affects males and females equally and sometimes runs in families – about a third of people with psoriasis have at least one family member with the condition. Psoriasis usually begins between the ages of 10 and 40, although people of all ages are susceptible.