ABSTRACT
Phototherapy is a valuable therapeutic option for many cutaneous disorders and has significantly enriched the treatment options in dermatology. The goals of therapeutic photomedicine are the prevention and reversal of disease processes through the modulation or suppression of pathogenic mechanisms. Ultraviolet B (UVB) phototherapy is based on repeated exposures to nonionizing radiation with wavelengths ranging from 290 nm to 320 nm and has been successfully used for decades to treat psoriasis and other inflammatory skin disorders. This chapter will provide a general overview of UVB in regard to psoriasis because it is one of the best-studied modalities for treating this very common inflammatory skin disease.
