Narrowband ultraviolet light therapy uses a small range of the ultraviolet light spectrum to treat skin conditions such as psoriasis. The light penetrates the skin and slows the growth of skin cells that cause skin lesions.
There are two types of ultraviolet (UV) light: narrowband and broadband. Narrowband light therapy is a more specific type of light therapy that allows the treatment to be given at a higher intensity over a shorter time. Clinical studies suggest that narrowband light may clear the skin lesions faster and result in longer periods of remission than broadband light therapy.