What exactly is psoriasis?
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Psoriasis is an immune-mediated disease. This means that your immune system causes your skin cells to reproduce in 4 days instead of 30 days, as is the case for skin without psoriasis.

Whereas normal skin cells are shed from people unnoticed, skin cells affected by psoriasis build up and form raised, scaly lesions.

Skin with psoriasis becomes red from the increased blood supply to the rapidly dividing cells, and the white scale is composed of dead skin cells.

Psoriasis goes through an unpredictable cycle: flares, improvement, remission and recurrence. It is not contagious.


The severity of each case depends on how much of your body has psoriasis lesions:

Mild cases involve only a few spots.

Moderate cases cover 3 to 10 percent of the body. (The palm of your hand represents 1 percent of the body's skin surface.) Severe cases involve more than 10 percent of the skin surface and may include all of a person's skin.

Onset & Flaring

Ordinarily, people have their first outbreak of psoriasis between the ages of 15 and 35, but it can appear at any age. Thirty percent of those who get psoriasis are less than 20 years old when the disease first surfaces.

Though psoriasis is believed to be an immune-mediated disease, heredity seems to play a part and so do environmental factors. About 25 percent of young people report the onset of their psoriasis followed an infection, particularly strep throat. One-third to one-half of all young people with psoriasis may experience a flare up two to six weeks after an earache, strep throat, bronchitis, tonsillitis or a respiratory infection.

Stress is thought to play a role in psoriasis, but stress alone is not a cause. Some studies have linked stress to psoriasis outbreaks and more severe progression of the disease, but other studies have found no connection between stress and psoriasis.


Psoriasis treatments-and there are many-work by slowing skin cell reproduction. Some work to remove scale. Some help soothe itchy or uncomfortable skin. All prescription psoriasis medications can be effective in improving lesions, but not all people with psoriasis react the same way to different medications. It may require experimentation to see which treatments, or combination of treatments, work for you.

There are three basic categories of psoriasis treatments:

1. Topical treatments like creams and ointments are used on the areas of skin that exhibit psoriasis plaques and lesions.

2. Ultraviolet light therapies (UVB and UVA) work by exposing the skin to light waves, sometimes over the whole body and sometimes only affected areas, like hands or feet.

3. Systemic medications are taken by mouth or injected into the body.

Dermatologists and other doctors prescribe treatments according to the type and severity of the psoriasis, the areas of the skin affected and your age and past medical history. Some of the treatments available for adults are used less often for teenagers because of the possibility of long-term or delayed side effects.

Ultraviolet Light B (UVB) Phototherapy

This type of treatment involves exposing the skin to a particular wavelength of ultraviolet light called ultraviolet light B (UVB). UVB is an effective treatment for psoriasis. It is present in natural sunlight. It is a common, safe and very effective treatment for moderate to severe psoriasis.

Two types of UVB treatment

There are two types of UVB treatment: broad-band UVB and narrow-band.

Narrow-band UVB units emit a more specific range of UV wavelengths than broad-band.

UVB treatment is used for adults and children. It is effective in at least two-thirds of patients who have thin plaques with moderate to severe disease. It is often used when topical treatments are not successful.

Some patients have had success by combining UVB with calcipotriene, tazarotene (brand name Tazorac), anthralin, coal tar, Methotrexate or acitretin.

How does it work?

It involves regularly treating the skin for a set length of time, either in a medical setting or with a home unit prescribed for the patient.

A person stands in a UVB unit containing lamps about 30 times, usually 2 or 3 times per week.

It is recommended that patients moisturize the morning of the light treatments.

The person undresses to expose all of the lesions to the light.

The length of time in the UVB unit depends on how quickly the person responds to light. People with lighter skin, for example, start out with lower exposure times than people with darker skin.

UVB works best when the person follows a regular treatment schedule and follows treatment carefully.

While in general ultraviolet light (sunlight) is known to cause skin cancer, there is no established link between office UVB treatments and skin cancer in psoriasis patients.

About half of those who try it will clear for about three months after stopping treatment, while others, particularly those using narrow-band, need about 8 maintenance sessions per month after the skin clears depending on the psoriasis severity and skin type.

Psoriasis may worsen for a while before improving.

The skin may itch and redden; the treatment may need to be reduced to avoid irritation.

The Goeckerman Regimen

People with severe or disabling psoriasis may go to a hospital for concentrated treatment with UVB and topical coal tar. This treatment is called the Goeckerman regimen, and usually takes five weeks of daily treatments. Most people will clear for about 6 to 12 months.

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