Psoriasis is a skin disorder that occurs when immune cells attack cells in the skin, causing them to divide abnormally quickly. This results in the formation of raised red plaques, which can be treated using ultraviolet light.
Mechanism
Ultraviolet light can be used to treat psoriasis because the light beams kill immune cells known as T cells, the National Institute of Arthritis and Musculoskeletal and Skin Disorders explains. Because these T cells mediate the immune reaction that causes psoriasis, this treatment can help reduce inflammation and make the psoriatic plaques fade.
Light Sources
Ultraviolet light can be found in sunlight, which means that patients can have their psoriasis treated by exposing affected parts of their skin to the sun. More controlled therapy can be achieved via the use of special lamps that emit ultraviolet light, the National Psoriasis Foundation explains.
Psoralen
Psoralen is a medication that can be used in combination with ultraviolet light therapy for psoriasis. This medication sensitizes the skin to a special wavelength of ultraviolet light, known as UV A. This treatment, which is also known as PUVA, can help treat chronic psoriasis and a special type of psoriasis known as guttate psoriasis, the National Psoriasis Foundation explains.
