Phototherapy is the use of a medical device that emits very specific wavelengths of ultraviolet light to treat skin diseases such as psoriasis and vitiligo.
Phototherapy is appropriate for those with moderate-to-severe skin diseases. Typically 3% to 10% body involvement is considered moderate, while 10% or more is considered severe.
A typical treatment regimen requires three treatments per week. In the beginning, treatment times may only last a few seconds, but will gradually increase in length over time. With psoriasis, clearance will typically require 25 to 30 consistent treatments.
Although, phototherapy is not a cure, approximately 85% of psoriasis patients achieve significant results with treatment. Symptoms may gradually reappear after several months of remission, therefore, a maintenance plan may be suggested to keep skin clear.