Lighting - UV Light to Treat Psoriasis

Light therapy is a clear proof that the role of lighting goes beyond what we normally understand using this term. Usually, when we say lighting we think illumination or light effects, or accent lighting. We rarely associate the term with a form of therapy, but light is used to treat various illnesses and it works; more or less. Light, in its different colors and form) is used to treat acne, eczema and psoriasis, sleep related disorders, depression (seasonal or non-seasonal) and it is believed to relieve even pain. Now let's take a look at a paradox: the harmful UV light is used to treat psoriasis.

The use of UV lighting to treat severe skin conditions is called phototherapy. One of the most severe skin conditions treated with ultra violet light is psoriasis. This is a very common skin disease, with many variations from psoriasis vulgaris (which is the most common form) to inverse psoriasis. The illness affects people of all ages, women and men with equal frequency. It is not transmissible; it occurs usually in the second decade of life and might remain a lifelong companion. The symptoms include irregular fingernail growth, raised and inflamed red lesions on the skin, covered with layers of dead skin cells and rarely, arthritis.

There is no cure for the disease, but there are some treatment options that could control the development of the skin lesions. Among them, use of UV lighting devices.

As you already know, UV light is harmful. There are three types of UV light: A, B and C. While UVC doesn't exist in its pure form in nature (the waves coming from the sun are getting absorbed in the atmosphere) UVB and UVA are present, yet not in sufficient amounts for people suffering from psoriasis. Too much of that light and we'll suffer too, for UV light might cause skin cancer, premature aging of the skin, cataracts and other problems, including DNA damage.

For the synthesis of vitamin D, we need UV-A, the least harmful of the three, but how does UV light help with psoriasis? Simple: it slows down the production of skin cells, thus helping to reduce inflammation. This is the very reason why overexposure causes skin disorders. Therefore, it is clear that UV light therapy should never be practiced in the absence of trained medics. The UVA light therapy method use to treat psoriasis is called PUVA. It combines psoralen and ultraviolet A. It is efficient on almost 85 % of the patients suffering from minor to medium forms of the disease. A number of 20-30 minute treatments are needed to start seeing obvious results. Too much UVA light and patients might experience adverse effects including nausea and burning.

UV-B is used alone or in combination with medicine. For example, the most popular form of treatment that employs UV-B is the Goeckerman regimen (UV-B plus coal tar). Other treatments are the Ingram method (which involves applying anthralin after a tar bath and UV-B light therapy) and a combination of UV-B with corticosteroids or other softening creams.