UV (Phototherapy) Treatments

Informaiton about UV and its use in the treatment of psoriasis.

Ultraviolet light (UV) is one of the standard psoriasis treatments. Whether it comes from the sun or from UVB cabinets, it will, for the majority of psoriatics, have a good effect, as UVB (UV light has three different bands, A, B and C) suppresses the immune system in the first few layers of the skin and also helps create Vitamin D Analogs.

Even with the effects of UV as well-known as they are, misinformation abounds. Tanning-salon equipment uses UVA light, which does not have nearly as pronounced an effect as UVB (or any effect at all), unless certain drugs called “psoralens” are either applied topically, or taken orally prior to UVA exposure (a regimen known as PUVA, for “Psoralen + UVA”). Some believe you need to get seconds away from burning for UVB to have an effect, which may not be the case (note that sunburn may cause new psoriasis outbreaks at the sites of skin damage, in a process known as Koebnerization).

“Sun and Surf” vacations have long been known to have great effects for many psoriatics, especially since soaking in the ocean can dissolve the dead skin on top of plaques, which blocks UVB light from getting to the live skin where it can do some good. For those psoriatics who find that their symptoms improve during the summer, and get worse in winter, such vacations may provide even greater relief, as long as one can stand the psychological impact of walking around with one’s plaques exposed to the world. See also the information on things like Dead Sea therapies.

Properly used UVB therapies do not seem to increase one’s risk for skin cancer. PUVA, on the other hand, does carry some risk, but properly-trained dermatologists will limit the UVA exposure as much as is possible while still allowing a therapeutic dose (lifetime limits are not so much based on number of treatments, as is often thought, but rather on total exposure). The “Sun and Surf” therapies are a mixture of UVA and UVB, and, as should be obvious, are difficult to control in terms of overall dosage of light received, and so a great deal of caution should be taken to not overdo it (such as rational use of sunscreen and limiting one’s exposure to avoid burning).