Psoriasis, an autoimmune disorder, is a chronic skin condition characterized by inflamed, red, raised areas that often develop into silvery scales on the scalp, elbows, knees, and lower back. Psoriasis can also be associated with arthritis. It is estimated to affect 7.5 million people in the U.S.
The cause of psoriasis is unknown; however, it is thought to be caused by abnormally fast-growing and shedding skin cells. The skin cells multiply quickly, causing the skin to shed every three to four days. This may be caused by a trigger, such as injury, sunburn, certain classes of medications, infection, stress, alcohol, or tobacco. Though not contagious, the condition is hereditary. Psoriasis is often recurrent and occurs in varying severities.
The following are the most common symptoms of psoriasis. Psoriasis comes in several forms and severities. Symptoms may include:
Discoid psoriasis (also called plaque psoriasis). This type of psoriasis is the most common. Symptoms may include patches of red, raised skin on the trunk, arms, legs, knees, elbows, genitals, and scalp. Nails may also thicken, become pitted, and separate from the nail beds.
Guttate psoriasis. This type of psoriasis affects mostly children. Symptoms may include many small patches of red, raised skin. A sore throat usually proceeds the onset of this type of psoriasis.
Pustular psoriasis. Symptoms may include small pustules (pus-containing blisters) all over the body or just on the palms, soles, and other small areas.
The symptoms of psoriasis may look like other skin conditions. Always consult your doctor for a diagnosis.
When the condition progresses to the development of silvery scales, the doctor can usually diagnose psoriasis with a medical examination of the nails and skin. Confirmation of diagnosis may be done with a skin biopsy (taking a small skin specimen to examine under a microscope).
Specific treatment for psoriasis will be determined by your doctor based on:
Your age, overall health, and medical history
Severity of the condition
Your tolerance of specific medications, procedures, or therapies
Expectations for the course of the condition
Your opinion or preference
The goal of treatment is to reduce inflammation and slow down the rapid growth and shedding of skin cells. At the present time, there is no cure for psoriasis. Treatment may include:
Ointments and creams (to moisturize the skin)
Sunlight or ultraviolet light exposure (under a doctor's supervision)
Steroids (such as cortisone creams)
Vitamin D cream
Creams containing salicylic acid or coal tar
Anthralin. An anti-inflammatory drug that treats the thicker, hard-to-treat patches of psoriasis.
Methotrexate. An anti-cancer drug that interrupts the growth of skin cells.
Oral or topical retinoids
Immunosuppressive medications (such as Cyclosporine)
Immunomodulary agents (biologic such as TNF-α inhibitors)
There is no known way to prevent psoriasis. Although it is a lifelong condition, it often can be controlled with appropriate treatment. Keeping the skin clean and moist, and avoiding person-specific psoriasis triggers (excessive stress, for example) may help decrease flare-ups.