Background

• Light therapy, also known as phototherapy, involves exposing skin to different wavelengths of light. Light therapy may be performed using lasers, light-emitting diodes (LEDs), fluorescent lamps, dichroic lamps, or very bright full-spectrum light. Treatments are performed regularly for a certain amount of time, under the supervision of healthcare professionals. Light therapy treatments may be given to the whole body or to smaller areas.
• Light therapy is a first-line treatment for jaundice in newborns (yellowing of skin in babies), severe plaque psoriasis (flaky, itchy skin disease), and seasonal affective disorder (SAD). It is also used for many skin conditions including atopic dermatitis (itchy skin disorder), acne, morphea (hardened skin patches), vitiligo (loss of color in skin), urticaria (hives), and pruritus (itchy skin). Treatment with light has been extended to other conditions, including nonseasonal mood disorders, memory loss, circadian-related sleep disorders, and eating disorders.
• Side effects of phototherapy are generally mild and short-term and include nausea, headache, and skin irritation. Like natural sunlight, long-term exposure to ultraviolet light may cause skin damage, skin cancer, or eye damage. Caution is needed in people who have a history of skin cancer or eye disease or are using agents that may increase their sensitivity to light.
• In general, studies on the use of light therapy have been small and poorly reported. More high-quality research is needed.

References

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