Psoriasis is a chronic skin disease that causes scaling and inflammation. Psoriasis occurs when skin cells quickly rise from below the surface of the skin and pile up before they have a chance to mature. This turnover of skin cells normally takes about a month, but in psoriasis, it may occur in only a few days. Psoriasis typically appears as patches of thick, red and inflamed skin covered with silvery scales. These patches are referred to as plaques and are often itchy or sore. They usually occur on the elbows, knees, parts of the legs, scalp, lower back, face, palms and soles of the feet, but can develop on any of the body’s skin surfaces.

Who Gets Psoriasis?

Psoriasis affects more than 5 million people in the United States. The disease can occur at any time, but mostly develops between the ages of 15 and 30. While psoriasis is found in all races, it is most often diagnosed in Caucasian patients, and affects men and women equally.

What Causes Psoriasis?

The exact cause of psoriasis is unknown, but it is believed that a combination of factors contribute to the development of the disease. An abnormality in the immune system causes inflammation in the skin, triggering new skin cells to develop too quickly. Normal skin cells are replaced every 28 to 30 days. With psoriasis, new skin cells grow and move to the surface of the skin every three to four days. The buildup of old cells creates the silver cells of psoriasis.

Common triggers include infection, stress, climate change, and skin trauma. In addition, certain medications such as beta blockers (propranolol), which are prescribed for high blood pressure, anti-malarials (hydroxychloroquine, chloroquine), and lithium may trigger an outbreak or worsen the disease.