Psoriasis is a chronic (long-lasting) skin disorder that causes scaling and inflammation. Psoriasis affects 2% to 3% of all people. It may develop as a result of an abnormality in the body's immune system, which normally fights infection and allergic reactions. Psoriasis probably involves heredity, because up to 40% of patients have family members with the same problem. Certain medications, such as lithium, a medication for bipolar disorder, may trigger psoriasis. Other medications, including beta-blockers, a class of heart and blood pressure medicines, seem to make psoriasis worse in people who already have the disease.

Psoriasis causes skin scaling and inflammation, with or without itching. There are several types of psoriasis:

• In plaque psoriasis, there are rounded or oval patches (plaques) of affected skin. These are usually red and covered with a thick silvery scale. The plaques often occur on the elbows, knees, scalp or near the buttocks. They may also appear on the trunk, arms and legs.



• Inverse psoriasis is a plaque type of psoriasis that tends to affect skin creases, especially those in the underarm, groin, buttocks, genital areas or under the breast. The red patches of inverse psoriasis may be moist rather than scaling.



• In pustular psoriasis, the skin patches are studded with pimples or pustules.



• In guttate (meaning droplike) psoriasis, many dime-sized or smaller red, scaly patches develop suddenly and simultaneously, often in a young person who has recently had a strep throat or a viral upper respiratory infection.

About 50% of people with skin symptoms of psoriasis also have abnormal fingernails, especially nail thickening or small indentations, called pitting. A type of arthritis, called psoriatic arthritis, can affect 10% to 20% of all people with psoriasis, and in some people, it occurs before skin changes appear.

Your health care professional will look for the typical skin and nail changes of this disorder.

Your doctor can frequently diagnose psoriasis based on the results of your physical examination. When skin symptoms are not typical of the disorder, your doctor may recommend a skin biopsy to confirm the diagnosis or to rule out other possible skin disorders. In a biopsy, a small sample of skin is removed and examined in a laboratory.

Psoriasis is a long-term disorder, although symptoms may come and go.

There is no way to prevent psoriasis.

Treatment for psoriasis varies depending on the type of psoriasis, the amount and location of affected skin, and the risks and benefits of each type of treatment.

• Topical treatments. These are treatments applied directly to the skin. They include daily skin care with emollients for lubrication, such as petroleum jelly or unscented moisturizers. Corticosteroid creams, lotions and ointments may be prescribed in medium and high-potency forms for applying to stubborn plaques on the hands, feet, arms, legs and trunk, and may be prescribed in low-potency forms for areas of delicate skin such as the face. Other treatments include calcipotriol (Dovonex), a synthetic form of vitamin D, which slows production of skin scales; tazarotene (Tazorac), a topical synthetic vitamin A derivative; coal tar; or salicylic acid to remove scales.



• Phototherapy. For extensive or widespread psoriasis, light treatment, using ultraviolet B or ultraviolet A, may be used alone or combined with coal tar. A treatment called PUVA (psoralin + UVA) combines ultraviolet A light treatment with an oral medication called psoralen, which improves the effectiveness of the light treatment. Laser treatment also can be used. It allows treatment of the involved skin to be more focused so that higher amounts of UV light can be used.



• Treatments for moderate to severe psoriasis involving large areas of the body. These include vitamin A derivatives -- acitretin (Soriatane), methotrexate (Folex, Methotrexate LPF, Rheumatrex) -- and cyclosporine (Neoral, Sandimmune). These treatments are very powerful, and some have the potential to cause severe side effects involving the liver, kidney or blood. Therefore, it's essential to understand the risks and be monitored closely. More rarely, the medications hydroxyurea (Hydrea) and azathioprine (Imuran) are prescribed for severe disease. Among the newest agents for psoriasis that has not responded to other treatments are the "biologics," medicines that act against naturally occurring cells or chemical messengers thought to promote psoriasis. Examples include alefacept (Amevive), etanercept (Enbrel) and infliximab (Remicade). Biologic treatments tend to be quite expensive and must be injected rather than taken as a pill.

If you are unsure whether you have psoriasis, contact your doctor. Also, contact your doctor if you know you have psoriasis and are not doing well with over-the-counter treatment.

For most patients, psoriasis is a long-term condition. Although there is no cure, there are many effective treatments. In some patients, doctors may switch treatments every 12 to 24 months to prevent the treatments from losing their effectiveness and to decrease the risk of side effects.

National Psoriasis Foundation
6600 SW 92nd Ave.
Suite 300
Portland, OR 97223-7195
Phone: 503-244-7404
Toll-Free: 1-800-723-9166
Fax: 503-245-0626
E-Mail: getinfo@psoriasis.org
http://www.psoriasis.org/