For thousands of years, healthcare providers have been “prescribing” sunlight for their patients. In some cases, it was the ultraviolet (UV) portion of that sunlight that was providing the real therapeutic benefit. Not only is UV phototherapy considered a mainstream dermatological treatment, it is also used in internal medicine (e.g. exposing blood to UV light to destroy certain pathogens).
Exposing the skin to ultraviolet radiation, either via sunlight or by a medical device, produces several biological reactions. The “suntan” and unfortunately the “sunburn” are very well known effects of exposure to UV light. A sun tan indicates damage to the skin which the body must heal. Over time, suntans and sunburns will cause the skin to look older prematurely. This effect is known as “photo-aging”. In some cases, too much exposure to UV light can cause skin cancer.
Other effects of exposure to the sun include suppressing the immune system of the skin, stimulating an increase in skin pigmentation, stimulating production of vitamin D, damaging the eyes, and destroying some forms of bacteria, viruses and fungus.
UV phototherapy is utilized for the treatment of diseases such as psoriasis, vitiligo, and eczema because UV light suppresses the immune system of the skin involved in disease propagation. UV light can destroy abnormally proliferating skin cells. UV light stimulates melanin production in functional melanocyctes, both in the skin and hair follicles, which increases skin pigmentation for patients with vitiligo.
UV phototherapy is typically administered by healthcare providers at their clinics, though home use units are available. Patients may pay cash for treatments, though health insurance typically covers UV phototherapy for a variety of conditions, including: