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 Light Therapy
and
Eye Safety


   The Lo-LIGHT Therapy Lamp
Cdn. patent # 1,334,399  U.S. patent # 5,447,527


Can Bright Light Therapy Damage the Eye?

Researchers have expressed concern regarding the use of bright light therapy because the visible blue light wavelengths emitted by these bright light therapy lamps may cause retinal damage and could contribute to the development of age related blindness. click for reference 1 on risk of Eye damage from bright light therapy This follows earlier cautions that users of bright light therapy lamps be screened by ophthalmologists, and that persons with pre-existing retinal conditions or other risk factors abstain from treatment or be closely monitored click for reference 1 on risk of Eye damage from bright light therapy

The patented light therapy technology used in a Lo-LIGHT therapy lamp eliminates this potential risk of retinal damage associated with "bright light" therapy lamps. Lo-LIGHT lamps are effective at normal indoor intensity. Lo-LIGHT therapy lamps also screen out the hazardous blue wavelengths of visible light that present the risk of damage to the retina.

People using "Bright Light" therapy while taking photosensitizing medications suffer an increased risk of eye damage. These medications, which sensitize the eye to damage by visible light, include nonsteroidal anti-inflammatory drugs (NSAIDs), most antidepressants, some antibiotics, diuretics, beta-blockers and other heart medications. Guidelines have been established recommending that "Bright-Light" therapy not be used with these photosensitizing medications.click for reference 2 on risk of Eye damage from bright light therapy

A case report in the American Journal of Psychiatry described a person who combined the use of "Bright Light" therapy and an antidepressant medication. After five days of using light therapy this patient suffered a "marked reduction in visual acuity contrast sensitivity."  Retinal examination found lesions in the retinas of both eyes.click for reference 2 on risk of Eye damage from bright light therapy

Other people, apart from those taking photosensitizing medications, should be particularly cautious about using "bright light" therapy. These include people with a pre-existing ocular condition or a susceptibility for retinal damage, such as those with diabetes. Older people should also be wary of bright light therapy. As we age, we experience a increased susceptibility to light-induced damage in retinal tissue, which results from an age-related decline in the ability of retinal defense mechanisms to repair oxidative damage.  This susceptibility increases the risk in older people of retinal damage and permanent blindness.click for reference 4 on risk of Eye damage from bright light therapy

Exposure to blue visible light causes oxidative damage in the retina.  Oxidative debris that results from this damage accumulates in the retina over a lifetime and is related to the development of age-related blindness. By age 75, more than one in every three people has Age-related Macular Degeneration (AMD), and this increases to over one half of people by age 85. 

It is worth considering what Herbert Kern, the first person to use bright light therapy and therefore the person with the longest history of bright light therapy use, said in the Sept 14, 2007 issue of Science regarding his developing AMD. After explaining that light therapy became less and less effective for him over the years as his eyesight faded, he said "Now I can hardly see, and all hell has broken loose" "I have had periods of depression lasting over a year, and highs lasting as long."

See Part II - Light exposure and AMD:  
FOR THERAPISTS AND EYE SAFETY EXPERTS: In the past two years a growing understanding of wavelength sensitivity in light therapy has led to speculation regarding the practicality of using blue light therapy.  For a more detailed discussion regarding  the risk of retinal damage from blue light therapy click 
Light therapy and retinal damage)  

Lo-LIGHT therapy is safe and comfortable for all users.

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