The majority of people with lupus are sensitive to ultraviolet light. This sensitivity is typically from ultraviolet B (UVB) rays, but some individuals can also be sensitive to ultraviolet A (UVA) rays. The sun and indoor fluorescent lights are constantly exposing us to ultraviolet light. Therefore, it is strongly recommended that people with lupus avoid ultraviolet light exposure by using sun-protective clothing, sunscreen, and sun block.

There is a potential risk of a lupus flare for the person with lupus who uses light therapy for seasonal affective disorder, or SAD. However, if the person demonstrates no photosensitivity, and the SAD is so severe that various therapies are not working, it could be considered. Anyone with lupus who is considering light therapy for SAD should first talk with their rheumatologist to weigh the potential risks and benefits.