Ultraviolet light therapy

Ultraviolet light therapy or ultraviolet phototherapy is a form of treatment for certain skin disorders including atopic skin disorder and vitiligo when used with psoralen to form the PUVA treatment. It consists of irradiation of the patient with the UVA band of ultraviolet light (fairly closely matching the ultraviolet output from the sun), usually delivered from a fluorescent bulb specially designed to output this frequency of ultraviolet.
This treatment is similar to the light from good quality solariums but differs from the mainly UVB ultraviolet band used to treat psoriasis. Tanning beds are used both in dermatology practices for the treatment of cosmetic skin conditions (such as psoriasis, acne, eczema and vitiligo) and in indoor tanning salons for cosmetic tanning. At least 88 percent of dermatologists recommend the usage of tanning equipment or salon tanning for clients to inexpensively self-treat skin conditions as a convenient alternative for clients in rural locations, as well as naturally occurring exposures including ultraviolet light from the sun.
Typical treatment regimens involve short exposure to UVB rays 3 to 5 times a week at a hospital or clinic, and repeated sessions may be required before results are noticeable. Almost all of the conditions that respond to UVB light are chronic problems, so continuous treatment is required to keep those problems in check. Home UVB systems are common solutions for those whose conditions respond to treatment. Home systems permit patients to treat themselves every other day (the ideal treatment regimen for most) without the frequent, costly trips to the office/clinic and back.
Side effects.
Side-effects may include itching and redness of the skin due to UVB exposure, and possibly sunburn, if patients do not minimize exposure to natural UV rays during treatment days. Cataracts can frequently develop if the eyes are not protected from UVB light exposure. To date, there is no link between an increase in a patient's risk of skin cancer and the proper use of narrow-band UVB phototherapy. "Proper use" is generally defined as reaching the "Sub-Erythemic Dose" (S.E.D.), the maximum amount of UVB your skin can receive "without" burning.
Certain fungal growths under the toenail can be treated using a specific wavelength of UV delivered from a high-power LED (light-emitting diode) and can be safer than traditional systemic drugs.
Phototherapy for neonatal jaundice in infants uses blue light, not UV.
Commercial tanning beds as alternative treatment.
Phototherapy is used for many dermatologic conditions. However, the time and expense can be a burden and obstacle for many patients. For patients with psoriasis, the use of tanning beds can be beneficial. (Psoriasis is a skin condition with symptoms of red flaky skin). Commercial tanning facilities offer an alternative means of phototherapy outside of a doctor's office. Tanning beds at commercial facilities are already being used by people with psoriasis; a survey showed that 36% of patients have tried commercial tanning beds to treat their psoriasis. Tanning beds are, in fact, the most common form of phototherapy.
However, there are risks to using tanning beds. Too much exposure to artificial UV light increases the risk of skin cancer. There are other side effects and risks from too much UV exposure, as well. People with lighter skin should take caution before using a tanning bed. Other issues include the UVA and UVB wavelength variable: there are many models of tanning beds, and it is highly variable among them as to what the combination of UVA and UVB wavelengths are used. UVA is primarily what tanning beds emit. UVA penetrates deeper into the skin, is less likely to cause sunburn, but increases the risk of skin cancer and melanoma.
One concern is that tanning beds that primarily emit UVA cannot be effective for the treatment of psoriasis. Other limitations to the use of tanning beds for the treatment of skin conditions include the imprecise output of the lamps and beds, imprecise spectral targeting of commercial tanning beds, the fact that the patient or non-medical staff run the machines, and other acute or long-term side effects.