Psoriasis is a disease affecting about 2% of the population.  The most common manifestation is scaly patches (known as plaques) on the elbows and knees.

Other types of psoriasis include pustular psoriasis, erythrodermic psoriasis, inverse psoriasis, guttate psoriasis, and psoriatic nail disease.

Psoriasis can also involve the joints, causing stiffness, pain and deformity.

Fortunately, there are many treatments available.  Mild disease is well-treated with creams and ointments.  Ultraviolet light or oral medications such as acetretin (Soriatane) and  methotrexate may be used for more widespread disease.  Newer drugs such as etanercept (Enbrel) and efalizumab (Raptiva) have also helped thousands of patients are are becoming the new standard for efficacy and safety.

The Psoriasis Foundation is an excellent organization that promotes education about and treatment of psoriasis.