How does the light therapy work
Light therapy is also known as phototherapy and is a physical method of treating psoriasis vulgaris. It is used for moderate to severe psoriasis or for large-area psoriasis. In light therapy, the affected skin is irradiated with ultraviolet light (UV light).
The irradiation can be done alone or in addition to a drug or local therapy. Narrow-spectrum UVB light is used, whereby light with a wavelength of between 311 and 331 nanometers strikes the skin. Another light therapy is the so-called PUVA therapy (psoralic UVB therapy), which works with a wavelength between 320 and 400 nanometers. In addition to treating the affected skin with UVA rays, the skin is also treated with the drug psoralen, which makes the skin more sensitive to UVA rays. Light therapy with UVB or UVA rays is generally intended to eliminate the inflammation in the skin affected by psoriasis by suppressing the overactive immune system and slowing down cell division, which is increased in psoriasis.
Is it possible to do the light therapy at home?
A professional light therapy cannot be performed at home, but takes place in dermatological practices or in a hospital. The light therapy is carried out with UVB or UVA rays. For this purpose, special devices with light tubes are used, which emit light in specific wavelengths.
Since it is important before treatment how high the dosage and wavelength of the UV light is, as well as how long the treatment should take place, treatment should only be carried out by dermatologists who are familiar with light therapy. In addition, the setting of the light irradiation depends on the skin type, on the intake of medications that make the skin more light-sensitive and on previous illnesses such as skin cancer. Preceding skin cancer is not only a limitation of the therapy, but also has to be considered with regard to the side effects of light therapy, as it increases the risk of skin cancer.
This is particularly important when irradiating with UVB radiation devices, which are available for sale over the counter. These are handy devices, for example a UVB light comb, which can be used independently for psoriasis on the scalp or other parts of the body. This treatment, if carried out, should only be carried out after consultation and with the agreement of a dermatologist.
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