Psoriasis

What is psoriasis?

Psoriasis is a common skin problem. It causes a thick, rough, dry buildup of the outer layer of skin. The thick areas of skin are called plaques. They usually occur on the scalp, elbows, knees, and buttocks, but they can develop anywhere on the skin.


People of all ages can have psoriasis. It is not contagious.

How does it occur?

When you have psoriasis, your outer layer of skin makes new cells more rapidly than normal. The extra cells become thick plaques. No one knows exactly what causes psoriasis, but most researchers believe it is an immune system disorder.


You are more likely to have psoriasis if members of your family have it.

What are the symptoms?

The symptoms are rough, dry, thick areas of skin. Often the skin under the plaques is slightly red. The skin may or may not itch.


Most psoriasis occurs in patches. Sometimes, however, it appears as many small, droplike, scaly areas. This is called guttate or raindrop psoriasis and it often occurs on the back.


Psoriasis can affect your fingernails and toenails, causing them to have pits or dents in them. In severe cases the nails become thick and misshapen.


A few people also have arthritis or joint pain with psoriasis.


The symptoms of psoriasis can vary from mild to severe. They may worsen when you are upset, sick, or injured. Flare-ups of the problem may also occur when:

  • You have a skin injury, such as a cut, burn, rash, or insect bite.
  • You drink a lot of alcohol (more than 1 drink a day for women, more than 2 drinks for men).
  • You have either very little exposure to sunlight or you have a severe sunburn.
  • Your skin is exposed to constant friction, for example, from clothing.

The severity of the symptoms may change with the seasons. Psoriasis usually gets better when you spend more time out in the sun.

How is it diagnosed?

Your health care provider will examine your skin and nails. For more information, your provider may do a skin biopsy. The biopsy is done by removing a small sample of your skin after the area has been numbed with an anesthetic.

How is it treated?

Your treatment depends on your symptoms. The goal is to ease discomfort and slow the production of skin cells to prevent or reduce the buildup of plaque.


Your health care provider will recommend or prescribe a cream or ointment to rub on your skin. A variety of medicines are available, such as:

  • steroid cream or ointment
  • salicylic acid cream or ointment
  • tar preparation (commonly ointment or shampoo)
  • anthralin cream or ointment
  • vitamin-D-like cream or ointment (calcipotriene).

A group of medicines called retinoids have been used to treat severe psoriasis. One of these, tazarotene, is a very potent gel used on the skin. This medicine may cause birth defects if it is used just before or during pregnancy. Another drug in this category is an oral medicine called acitretin, which is also very likely to cause birth defects.


More severe psoriasis may require medicines to suppress your body's immune response. Examples of such medicines are methotrexate and cyclosporin, which are usually taken by mouth. Another example is a medicine called Amevive (alefacept). It prevents your immune system from overreacting and so helps stop the buildup of extra skin cells. It is given as a shot once a week for 12 weeks. You will need some monitoring with blood tests while you are using these medicines.


Your health care provider may want you to use more than one type of medicine. If you are using a combination of psoriasis medicines, it is helpful to keep a record of when you use each medicine and review it with your provider at your checkups.


Your health care provider may prescribe ultraviolet (UV) light therapy in addition to your medicines.

How long will the effects last?

Psoriasis is a chronic disease, which means you will likely have it all of your life. The extent and severity of the disease vary widely. Early treatment of the plaques may help stop the problem from becoming more severe.

How can I help take care of myself?

To help reduce flare-ups:

  • Try to avoid skin injuries. When you do injure your skin, protect your skin from infection.
  • Avoid stress.
  • Exercise daily according to your health care provider's recommendation and maintain a healthy weight.
  • Avoid drinking too much alcohol.
  • Follow your provider's recommendations for keeping your skin soft. Ask your provider to suggest soaps, lotions, and cosmetics.

How can I help prevent psoriasis?

Because the cause of psoriasis is not known, it is not yet possible to prevent it. However, you may be able to prevent serious outbreaks by treating small plaques when you first see them. Follow your health care provider's instructions for treatment.


For more information, contact:


The National Psoriasis Foundation
Phone: 800-723-9166
Web site: http://www.psoriasis.org


The Foundation provides educational materials, referrals to specialists, and staff to answer questions.


Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available. The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.


HIA File SKN4864F.HTM Release 9.0/2006

Copyright © 2006 McKesson Corporation and/or one of its subsidiaries. All Rights Reserved.

Copyright © 2006 McKesson Corporation and/or one of its subsidiaries. All Rights Reserved.