Psoriasis - Phototherapy

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Highlights	Diagnosis	Managing Psoriasis
Introduction	Treatment	Outlook
Types of Psoriasis	Topical Medications	Resources
Causes	Systemic Medications	References
Risk Factors	Phototherapy

The following safety features should be available in the PUVA chamber:

Lamps with protective shields
A viewing window for a health care professional to check the patient periodically
A door that can be opened by the patient easily and with little pressure
A timer that ends the session automatically
An accessible alarm device

Protective Measures After Treatment. The drugs used in PUVA make patients more likely to get a natural sunburn for a few hours after treatment. Patients should take the following precautions:

Wear UVA absorbing wrap-around sunglasses that are designed to completely block out stray radiation. Patients should begin wearing them as soon as they take the drug, and for at least 12 hours after the treatment. This is important to prevent a PUVA reaction around the eyes that can cause cataracts. There is no need to wear these glasses after sundown.
For about 8 hours after taking the drug, avoid exposure to daylight, even if the day is cloudy or exposure is only through windows.
Wear heavy opaque clothing (clothes that do not let light through) outside, including hats and gloves.
Apply sunblock over all exposed areas, including the lips. The sunblock should have a sun protection factor (SPF) of more than 15 and include ingredients that block both UVB and UVA radiation.
Do not spend a long time in sunlight for at least 2 days after the combined treatment.

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UVB Therapy

Ultraviolet B is another part of sunlight, and is the main cause of sunburn. It generally affects the outer skin layers. UVB radiation reduces the abnormally rapid skin cell growth that occurs with psoriasis.

Types of UVB therapy:

Broadband UVB
Narrowband UVB (NB-UVB)
Laser treatments

Broadband Ultraviolet B (UVB) Radiation

Broad spectrum or broadband UVB is radiation in the wavelength of 290 - 350 nanometers, and is the standard UVB phototherapy treatment in the United States. It is not as potent as the treatments that use narrowband UVB or PUVA, and is not useful for chronic psoriasis.

Broadband UVB may be given with or without medications. When used without medication (known as selective ultraviolet phototherapy), UVB treatment is generally given as follows: