Table of ContentsView AllTable of ContentsConditionsTypesHow it WorksSide Effects and Risks
Table of ContentsView All
View All
Table of Contents
Conditions
Types
How it Works
Side Effects and Risks
Phototherapy is a medical treatment in which natural or artificial light is used to improve a health condition. Treatment may involve ultraviolet (UV) fluorescent light bulbs, halogen lights, sunlight, or light-emitting diodes (LEDs).
Other names for phototherapy include light therapy and heliotherapy. The type of therapy you need and the way in which the light is used can vary depending on whether the phototherapy is for eczema, psoriasis, or other health conditions.
This article explains how light therapy is used to treat these conditions. It also discusses some of the risks involved.
Verywell / Brianna Gilmartin
What Conditions Does Phototherapy Treat?
Phototherapy is used to treat skin conditions, certain types of cancer and precancer, and mood and sleep disorders. Specific health problems phototherapy can help include:
Types of Phototherapy
Phototherapy describes several different therapies that use light to treat health conditions. The type of phototherapy used depends on the reason for treatment and include:
PUVA has more side effects than some other light therapies. It’s only used when other options haven’t worked.
How Phototherapy Works
The way in which phototherapy works depends on the type of treatment and what it is being used to treat.
Phototherapy for Skin Conditions
Phototherapy treatment for skin conditions involves using ultraviolet (UV) light to slow skin cell growth andinflammation. Inflammation is one of the ways your immune system responds to infections, injuries, and foreign “invaders.”
UVB rays affect the outermost layers of the skin. UVA rays are slightly less intense but penetrate more deeply into the skin. These two types of UV light can be used in different ways.
Skin conditions treated with phototherapy include:
The effects of light therapy for skin disorders are usually temporary. Phototherapy for skin conditions may take six to eight sessions and up to two months to work.
Phototherapy for skin conditions is generally considered safe. However, side effects include redness, dry or itchy skin, nausea (with PUVA), blisters, orfolliculitis, an infection of the hair follicles. Long-term side effects include skin cancer and premature skin aging.
Phototherapy for Mood and Sleep Disorders
Bright light therapy is a type of phototherapy used to treat mood and sleep disorders. It involves using alightbox—a specially designed box that emits a steady light that mimics sunlight.
Seasonal Affective Disorder (SAD)
Seasonal affective disorder(SAD) is a type of depression linked to certain seasons of the year. It usually begins in the fall and lasts through winter. Bright light therapy helps to relieve the symptoms of SAD.
Light therapy is an inexpensive and effective treatment with side effects that are mild and temporary.
If you take an antidepressant, light therapy may make it possible to lower the amount of medication you use. However, talk to your healthcare provider first before changing your antidepressant dose.Stopping your antidepressanthas some health risks.
Phototherapy has also been explored for other kinds of depression. Some studies support it, but not all health experts agree that light therapy helps with depression.
Sleep Disorders
Your body has an inner “clock” that times your sleeping and waking cycles. It’s known as yourcircadian rhythm, and it doesn’t always work the way it should.
Light therapy can help those who have circadian rhythm sleep disorders such asdelayed sleep phase syndrome(DSPS). People with DSPS often can’t fall asleep until the wee hours of the morning or close to sunrise. Light therapy can help them shift to more normal sleeping times.
It’s important to time the light therapy correctly. Your sleep specialist will help you plan the right time to use light based on your symptoms.
Phototherapy for Cancers and Precancers
Photodynamic therapy is the form of light therapy used to treat some kinds of cancer and precancers.It involves using a drug called a photosensitizer along with light.
Photodynamic therapy is used to treat conditions such as:
Photodynamic therapy is sometimes called photoradiation therapy or photochemotherapy.
Phototherapy has some advantages over treatments like radiation and chemotherapy. For example, it doesn’t usually have any long-term side effects. It leaves less scarring than surgery. And phototherapy costs a lot less than the other treatment options for cancer.
The downside is that it usually only works in areas on or just under the skin, where light can reach. It also does not help much with cancers that have spread.
Phototherapy for Newborn Jaundice
Compact fluorescent lights and blue LED devices are also used to give babies phototherapy. They can be kept close to the body because they do not produce a lot of heat.
Light therapy for treating hyperbilirubinemia and jaundice is considered very safe. However, people sometimes have short-term side effects such as diarrhea, rashes, overheating, and water loss or dehydration.
Phototherapy Side Effects and Risks
Side effects and risks of phototherapy depend on the type of light therapy used.
Phototherapy for skin conditions carries the following risks:
Bright light therapy for mood disorders also has a number ofside effectsyou should be aware of. They include:
Bili light therapy can cause dehydration. Newborns undergoing treatment for jaundice may be given IV fluids.
Who Should Avoid Phototherapy?People with certain health conditions may need to avoid light therapy. Make sure your healthcare provider knows about your condition if you:Are pregnant or breastfeedingHave a family history of skin cancerHave liver diseaseHave lupus
Who Should Avoid Phototherapy?
People with certain health conditions may need to avoid light therapy. Make sure your healthcare provider knows about your condition if you:Are pregnant or breastfeedingHave a family history of skin cancerHave liver diseaseHave lupus
People with certain health conditions may need to avoid light therapy. Make sure your healthcare provider knows about your condition if you:
Summary
Light therapy can be used to treat skin conditions, mood disorders, sleep disorders, some cancers, and jaundice in babies. Some treatments involve exposure to natural or artificial light. Others combine light therapy with a drug that makes the light more effective.
While light therapy is considered safe, some people do have side effects. And it’s not right for everyone. If you’re pregnant or nursing, have a family history of skin cancer, or have liver disease or lupus, light therapy might not be helpful.
Light Therapy for Psoriasis
15 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Barros NM, Sbroglio LL, Buffara MO, Baka JLCES, Pessoa AS, Azulay-Abulafia L.Phototherapy.An Bras Dermatol. 2021;96(4):397-407. doi: 10.1016/j.abd.2021.03.001.U.S. National Library of Medicine: MedlinePlus.Bili lights.Campbell PD, Miller AM, Woesner ME.Bright light therapy: seasonal affective disorder and beyond.Einstein J Biol Med. 2017;32:E13-E25.Elmets CA, Lim HW, Stoff B, et al.Joint American Academy of Dermatology-National Psoriasis Foundation guidelines of care for the management and treatment of psoriasis with phototherapy.J Am Acad Dermatol. 2019;81(3):775-804. doi:10.1016/j.jaad.2019.04.042Memorial Sloan Kettering Cancer Care.About Your Phototherapy Procedure.Campbell PD, Miller AM, Woesner ME.Bright light therapy: Seasonal affective disorder and beyond.Einstein J Biol Med. 2017;32:E13-E25.Perera S, Eisen R, Bhatt M, et al.Light therapy for non-seasonal depression: systematic review and meta-analysis.BJPsych Open. 2016;2(2):116-126. doi:10.1192/bjpo.bp.115.001610Figueiro MG.Delayed sleep phase disorder: clinical perspective with a focus on light therapy.Nat Sci Sleep. 2016;8:91-106. doi:10.2147/NSS.S85849Nguyen K, Khachemoune A.An update on topical photodynamic therapy for clinical dermatologists.J Dermatolog Treat. 2019 Dec;30(8):732-744. doi:10.1080/09546634.2019.1569752Ebbesen F, Hansen TWR, Maisels MJ.Update on phototherapy in jaundiced neonates.Curr Pediatr Rev. 2017;13(3):176-180. doi:10.2174/1573396313666170718150056Abdulkadir I, Slusher TM.Neonatal Eye Shielding during Phototherapy: What Protects the Eye Better?J Trop Pediatr. 2021 Dec 8;67(6):fmab101. doi:10.1093/tropej/fmab101.Narayanan DL, Saladi RN, Fox JL.Ultraviolet radiation and skin cancer.Int J Dermatol. 2010;49(9):978-986. doi:10.1111/j.1365-4632.2010.04474.xLin TL, Wu CY, Chang YT, et al.Risk of skin cancer in psoriasis patients receiving long-term narrowband ultraviolet phototherapy: Results from a Taiwanese population-based cohort study.Photodermatol Photoimmunol Photomed. 2019;35(3):164-171. doi:10.1111/phpp.12443Maiorino A, De Simone C, Perino F, Caldarola G, Peris K.Melanoma and non-melanoma skin cancer in psoriatic patients treated with high-dose phototherapy.J Dermatolog Treat. 2016;27(5):443-7. doi: 10.3109/09546634.2015.1133882.Legat FJ.The antipruritic effect of phototherapy.Front Med. 2018;5:333. doi:10.3389/fmed.2018.00333Additional ReadingNankervis H, Thomas KS, Delamere FM, Barbarot S, Rogers NK, Williams HC.Phototherapy treatment. In:Scoping Systematic Review of Treatments for Eczema. Southampton, UK: NIHR Journals Library; 2016.
15 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Barros NM, Sbroglio LL, Buffara MO, Baka JLCES, Pessoa AS, Azulay-Abulafia L.Phototherapy.An Bras Dermatol. 2021;96(4):397-407. doi: 10.1016/j.abd.2021.03.001.U.S. National Library of Medicine: MedlinePlus.Bili lights.Campbell PD, Miller AM, Woesner ME.Bright light therapy: seasonal affective disorder and beyond.Einstein J Biol Med. 2017;32:E13-E25.Elmets CA, Lim HW, Stoff B, et al.Joint American Academy of Dermatology-National Psoriasis Foundation guidelines of care for the management and treatment of psoriasis with phototherapy.J Am Acad Dermatol. 2019;81(3):775-804. doi:10.1016/j.jaad.2019.04.042Memorial Sloan Kettering Cancer Care.About Your Phototherapy Procedure.Campbell PD, Miller AM, Woesner ME.Bright light therapy: Seasonal affective disorder and beyond.Einstein J Biol Med. 2017;32:E13-E25.Perera S, Eisen R, Bhatt M, et al.Light therapy for non-seasonal depression: systematic review and meta-analysis.BJPsych Open. 2016;2(2):116-126. doi:10.1192/bjpo.bp.115.001610Figueiro MG.Delayed sleep phase disorder: clinical perspective with a focus on light therapy.Nat Sci Sleep. 2016;8:91-106. doi:10.2147/NSS.S85849Nguyen K, Khachemoune A.An update on topical photodynamic therapy for clinical dermatologists.J Dermatolog Treat. 2019 Dec;30(8):732-744. doi:10.1080/09546634.2019.1569752Ebbesen F, Hansen TWR, Maisels MJ.Update on phototherapy in jaundiced neonates.Curr Pediatr Rev. 2017;13(3):176-180. doi:10.2174/1573396313666170718150056Abdulkadir I, Slusher TM.Neonatal Eye Shielding during Phototherapy: What Protects the Eye Better?J Trop Pediatr. 2021 Dec 8;67(6):fmab101. doi:10.1093/tropej/fmab101.Narayanan DL, Saladi RN, Fox JL.Ultraviolet radiation and skin cancer.Int J Dermatol. 2010;49(9):978-986. doi:10.1111/j.1365-4632.2010.04474.xLin TL, Wu CY, Chang YT, et al.Risk of skin cancer in psoriasis patients receiving long-term narrowband ultraviolet phototherapy: Results from a Taiwanese population-based cohort study.Photodermatol Photoimmunol Photomed. 2019;35(3):164-171. doi:10.1111/phpp.12443Maiorino A, De Simone C, Perino F, Caldarola G, Peris K.Melanoma and non-melanoma skin cancer in psoriatic patients treated with high-dose phototherapy.J Dermatolog Treat. 2016;27(5):443-7. doi: 10.3109/09546634.2015.1133882.Legat FJ.The antipruritic effect of phototherapy.Front Med. 2018;5:333. doi:10.3389/fmed.2018.00333Additional ReadingNankervis H, Thomas KS, Delamere FM, Barbarot S, Rogers NK, Williams HC.Phototherapy treatment. In:Scoping Systematic Review of Treatments for Eczema. Southampton, UK: NIHR Journals Library; 2016.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Barros NM, Sbroglio LL, Buffara MO, Baka JLCES, Pessoa AS, Azulay-Abulafia L.Phototherapy.An Bras Dermatol. 2021;96(4):397-407. doi: 10.1016/j.abd.2021.03.001.U.S. National Library of Medicine: MedlinePlus.Bili lights.Campbell PD, Miller AM, Woesner ME.Bright light therapy: seasonal affective disorder and beyond.Einstein J Biol Med. 2017;32:E13-E25.Elmets CA, Lim HW, Stoff B, et al.Joint American Academy of Dermatology-National Psoriasis Foundation guidelines of care for the management and treatment of psoriasis with phototherapy.J Am Acad Dermatol. 2019;81(3):775-804. doi:10.1016/j.jaad.2019.04.042Memorial Sloan Kettering Cancer Care.About Your Phototherapy Procedure.Campbell PD, Miller AM, Woesner ME.Bright light therapy: Seasonal affective disorder and beyond.Einstein J Biol Med. 2017;32:E13-E25.Perera S, Eisen R, Bhatt M, et al.Light therapy for non-seasonal depression: systematic review and meta-analysis.BJPsych Open. 2016;2(2):116-126. doi:10.1192/bjpo.bp.115.001610Figueiro MG.Delayed sleep phase disorder: clinical perspective with a focus on light therapy.Nat Sci Sleep. 2016;8:91-106. doi:10.2147/NSS.S85849Nguyen K, Khachemoune A.An update on topical photodynamic therapy for clinical dermatologists.J Dermatolog Treat. 2019 Dec;30(8):732-744. doi:10.1080/09546634.2019.1569752Ebbesen F, Hansen TWR, Maisels MJ.Update on phototherapy in jaundiced neonates.Curr Pediatr Rev. 2017;13(3):176-180. doi:10.2174/1573396313666170718150056Abdulkadir I, Slusher TM.Neonatal Eye Shielding during Phototherapy: What Protects the Eye Better?J Trop Pediatr. 2021 Dec 8;67(6):fmab101. doi:10.1093/tropej/fmab101.Narayanan DL, Saladi RN, Fox JL.Ultraviolet radiation and skin cancer.Int J Dermatol. 2010;49(9):978-986. doi:10.1111/j.1365-4632.2010.04474.xLin TL, Wu CY, Chang YT, et al.Risk of skin cancer in psoriasis patients receiving long-term narrowband ultraviolet phototherapy: Results from a Taiwanese population-based cohort study.Photodermatol Photoimmunol Photomed. 2019;35(3):164-171. doi:10.1111/phpp.12443Maiorino A, De Simone C, Perino F, Caldarola G, Peris K.Melanoma and non-melanoma skin cancer in psoriatic patients treated with high-dose phototherapy.J Dermatolog Treat. 2016;27(5):443-7. doi: 10.3109/09546634.2015.1133882.Legat FJ.The antipruritic effect of phototherapy.Front Med. 2018;5:333. doi:10.3389/fmed.2018.00333
Barros NM, Sbroglio LL, Buffara MO, Baka JLCES, Pessoa AS, Azulay-Abulafia L.Phototherapy.An Bras Dermatol. 2021;96(4):397-407. doi: 10.1016/j.abd.2021.03.001.
U.S. National Library of Medicine: MedlinePlus.Bili lights.
Campbell PD, Miller AM, Woesner ME.Bright light therapy: seasonal affective disorder and beyond.Einstein J Biol Med. 2017;32:E13-E25.
Elmets CA, Lim HW, Stoff B, et al.Joint American Academy of Dermatology-National Psoriasis Foundation guidelines of care for the management and treatment of psoriasis with phototherapy.J Am Acad Dermatol. 2019;81(3):775-804. doi:10.1016/j.jaad.2019.04.042
Memorial Sloan Kettering Cancer Care.About Your Phototherapy Procedure.
Campbell PD, Miller AM, Woesner ME.Bright light therapy: Seasonal affective disorder and beyond.Einstein J Biol Med. 2017;32:E13-E25.
Perera S, Eisen R, Bhatt M, et al.Light therapy for non-seasonal depression: systematic review and meta-analysis.BJPsych Open. 2016;2(2):116-126. doi:10.1192/bjpo.bp.115.001610
Figueiro MG.Delayed sleep phase disorder: clinical perspective with a focus on light therapy.Nat Sci Sleep. 2016;8:91-106. doi:10.2147/NSS.S85849
Nguyen K, Khachemoune A.An update on topical photodynamic therapy for clinical dermatologists.J Dermatolog Treat. 2019 Dec;30(8):732-744. doi:10.1080/09546634.2019.1569752
Ebbesen F, Hansen TWR, Maisels MJ.Update on phototherapy in jaundiced neonates.Curr Pediatr Rev. 2017;13(3):176-180. doi:10.2174/1573396313666170718150056
Abdulkadir I, Slusher TM.Neonatal Eye Shielding during Phototherapy: What Protects the Eye Better?J Trop Pediatr. 2021 Dec 8;67(6):fmab101. doi:10.1093/tropej/fmab101.
Narayanan DL, Saladi RN, Fox JL.Ultraviolet radiation and skin cancer.Int J Dermatol. 2010;49(9):978-986. doi:10.1111/j.1365-4632.2010.04474.x
Lin TL, Wu CY, Chang YT, et al.Risk of skin cancer in psoriasis patients receiving long-term narrowband ultraviolet phototherapy: Results from a Taiwanese population-based cohort study.Photodermatol Photoimmunol Photomed. 2019;35(3):164-171. doi:10.1111/phpp.12443
Maiorino A, De Simone C, Perino F, Caldarola G, Peris K.Melanoma and non-melanoma skin cancer in psoriatic patients treated with high-dose phototherapy.J Dermatolog Treat. 2016;27(5):443-7. doi: 10.3109/09546634.2015.1133882.
Legat FJ.The antipruritic effect of phototherapy.Front Med. 2018;5:333. doi:10.3389/fmed.2018.00333
Nankervis H, Thomas KS, Delamere FM, Barbarot S, Rogers NK, Williams HC.Phototherapy treatment. In:Scoping Systematic Review of Treatments for Eczema. Southampton, UK: NIHR Journals Library; 2016.
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