Psoriasis is a skin condition that creates thick, pink/red plaque of skin with overlying white, flaky scales. It most commonly occurs on the elbows, knees and trunk, but can appear anywhere on the body. The first episode usually strikes between the ages of 15 and 35. It is a chronic condition that will then cycle through flare-ups and remissions throughout the rest of the patient's life. Psoriasis affects up to 2% of the U.S. population.

In normal skin, skin cells live for about 28 days and then are shed from the outermost layer of the skin. With psoriasis, the body's immune system attacks itself, which speeds up the growth cycle of skin cells. Skin cells mature in a matter of 3 to 6 days. The pace is so rapid that the body is unable to shed the dead cells, and patches of raised red skin covered by scaly, white flakes form on the skin.

Psoriasis is a genetic disease (it runs in families), but is not contagious. There is no known cure or method of prevention. Treatment aims to minimize the symptoms and speed healing.

Psoriasis is much more than just a skin disease--it is truly a systemic inflammatory illness, and many skin patients are also affect by a destruction joint disease called psoriatic arthritis. People who have psoriasis are at greater risk for contracting other health problems, such as heart disease, inflammatory bowel disease and diabetes. It has also been linked to a higher incidence of cardiovascular disease, hypertension, cancer, depression, obesity and other immune-related conditions.

Types of Psoriasis

There are five types of psoriasis:

  • Plaque Psoriasis (Psoriasis Vulgaris) — About 80% of all psoriasis sufferers get this form of the disease. It is typically found on the elbows, knees, scalp and lower back. It classically appears as inflamed, red lesions covered by silvery-white scales.
  • Guttate Psoriasis This form of psoriasis appears as small red dot-like spots, usually on the trunk or limbs. It occurs most frequently among children and young adults. Guttate psoriasis comes on suddenly, often in response to some other health problem or environmental trigger, such as strep throat, tonsillitis, stress or injury to the skin.
  • Inverse Psoriasis — This type of psoriasis appears as bright red lesions that are smooth and shiny. It is usually found in the underarms, groin, under the breasts and in skin folds around the genitals and buttocks.
  • Pustular Psoriasis — Pustular psoriasis looks like white blisters filled with pus surrounded by red skin. It can appear in a limited area of the skin or all over the body. The pus is made up of white blood cells and is not infectious. Triggers for pustular psoriasis include overexposure to ultraviolet radiation, irritating topical treatments, stress, infections and sudden withdrawal from systemic (treating the whole body) medications.
  • Erythrodermic Psoriasis — One of the most inflamed forms of psoriasis, erythrodermic psoriasis looks like fiery, red skin covering large areas of the body that shed in white sheets instead of flakes. This form of psoriasis is usually very itchy and may cause some pain. Triggers for erythrodermic psoriasis include severe sunburn, infection, pneumonia, medications or abrupt withdrawal of systemic psoriasis treatment. This can be a life-threatening condition.

Treatment

Psoriasis is classified as mild to moderate when it covers <1% to 10% of the body and moderate to severe when it covers more than 10% of the body. Location of disease also changes severity, because a patient with palm and sole disease may be disabled as opposed to a patient with lesions on the elbows, knees and buttocks. The severity of the disease impacts the choice of treatments.

Mild to Moderate Psoriasis

Mild to moderate psoriasis can generally be treated using a combination of three key strategies: over-the-counter moisturizers, prescription topical treatments and possibly light therapy/phototherapy.

Over-the-Counter Medications

  • Scale lifters such as salicylic acid that help loosen and remove scales so that medicine can reach the lesions.
  • Bath solutions, like oatmeal, Epsom salts or Dead Sea salts
  • Anti-itch agents, such as calamine lotion or hydrocortisone creams.
  • Moisturizers such as petrolatum designed to keep the skin lubricated, reduce redness and itchiness and promote healing.

Prescription Topical Treatments

Prescription topical agents focus on slowing down the growth of skin cells and reducing inflammation.

  • Anthralin, used to reduce the rapid growth of skin cell.
  • Calcipotriene, a synthetic form of vitamin D3 that slows cell growth, flattens lesions and removes scales
  • Calcitriol, an active form of vitamin D3 that helps control excessive skin cell production.
  • Tazarotene, a topical retinoid used to slow cell growth.
  • Topical steroids, are designed to reduce the inflammation of psoriasis lesions
  • Combination medications, such as Calcipotriene combined with the steroid betamethasone dipropionate which allow for 2 medications to be applied with one application

Light Therapy/Phototherapy

Controlled exposure of skin to ultraviolet light has been a successful treatment for some forms of psoriasis. Three primary light sources are used:

  • Sunshine (both UVA and UVB rays). Sunshine can help alleviate the symptoms of psoriasis, but must be used with careful monitoring to ensure that no other skin damage takes place. It is advised that exposure to sunshine be in controlled, short bursts.
  • Excimer lasers. These devices are used to target specific areas of psoriasis. The laser emits a high-intensity beam of UVB directly onto the psoriasis plaque. It generally takes between 4 and 10 treatments to see a tangible improvement.
  • Pulse dye lasers. Similar to the excimer laser, a pulse dye laser uses a different wavelength of UVB light. In addition to treating smaller areas of psoriasis, it destroys the blood vessels that contribute to the formation of lesions. It generally takes about 4 to 6 sessions to clear up a small area with a lesion.

Moderate to Severe Psoriasis

Treatments for moderate to severe psoriasis include prescription medications, biologics and light therapy/phototherapy.

Oral medications. This includes acitretin, cyclosporine and methotrexate. Your doctor will recommend the best oral medication based on the location, type and severity of your condition. These agents can be very effective, but are serious medications that require monitoring because of potential side effects.

Biologics. A relatively new, exciting class of  injectable drugs, biologics are designed to suppress the immune system in a very targeted fashion. These tend to be very expensive and have side effects, so they are generally reserved for the most severe cases or patients who have failed other options.

Light Therapy/Phototherapy. Can be used alone or in combination with some of the above medications such as methotrexate or acitretin.

For more information, please visit the National Psoriasis Foundation's website at

www.psoriasis.org