Skin treatments using blue and violet light

Abstract

Aging or damaged skin is treated by irradiating affected skin areas with an effective amount of blue and/or violet visible light having a wavelength of about 400 nm to about 500 nm. The light may be sunlight or artificial light, coherent or noncoherent, pulsed or continuous, of high or low energy, exposed generally or directed to target areas, or any combination of these. A variety of irradiation methods may be employed. In one embodiment, filtered sun or artificial light is used. This can be widely exposed to skin areas, or directed to discrete skin regions, particularly to areas especially susceptible to aging, e.g., the backs of hands and the periorbital and perioral areas of the face. In an alternate embodiment, light-emitting diodes are applied directly to discrete skin areas as needed as patches or thin sheets such as pliable masks. Green light (about 500 to about 590 nm) may be used as adjunct therapy with blue/violet light in some embodiments. Compositions containing compounds that enhance light penetration of the stratum corneum such as α-hydroxy acids (e.g., glycolic acid) and/or filter light may be applied to the skin prior to or during phototreatment.

1 . A method for treating aging or damaged skin comprising irradiating the skin with an effective amount of visible light having a wavelength of about 400 nm to about 500 nm.  
     
     
         2 . A method according to  claim 1  wherein the light has an intensity of below about 800 mW/cm 2 .  
     
     
         3 . A method according to  claim 1  wherein the light has an intensity of above about 800 mW/cm 2 .  
     
     
         4 . A method according to  claim 1  wherein the light is continuously illuminated on the skin.  
     
     
         5 . A method according to  claim 1  wherein the light is pulsed.  
     
     
         6 . A method according to  claim 1  wherein the light is generated from a lamp.  
     
     
         7 . A method according to  claim 1  wherein the light is filtered sunlight.  
     
     
         8 . A method according to  claim 1  wherein the light is laser light.  
     
     
         9 . A method according to  claim 1  wherein the light is emitted from a light-emitting diode.  
     
     
         10 . A method according to  claim 9  wherein the light-emitting diode is applied directly to the skin as a patch or thin sheet.  
     
     
         11 . A method according to  claim 1  wherein the skin is also irradiated with visible light having a wavelength of about 500 to about 590 nm.  
     
     
         12 . A method according to  claim 1  wherein the skin is treated with a dermatological composition containing a chemical filter prior to irradiation.  
     
     
         13 . A method according to  claim 1  wherein the skin is treated with a dermatological composition containing a physical filter prior to irradiation.  
     
     
         14 . A method according to  claim 1  wherein the skin is treated with a dermatological composition that enhances the optical transparency of the stratum corneum prior to irradiation.  
     
     
         15 . A method according to  claim 14  wherein the composition comprises an α-hydroxy acid.  
     
     
         16 . A method according to  claim 15  wherein the α-hydroxy acid is glycolic acid.  
     
     
         17 . A method for treating aging or damaged skin comprising irradiating the skin with an effective amount of filtered blue/violet sunlight having a wavelength of about 400 nm to about 500 nm.  
     
     
         18 . A method according to  claim 17  wherein the skin is irradiated through an umbrella, visor, or hat brim comprising a blue/violet filter.  
     
     
         19 . A method according to  claim 17  wherein the skin is irradiated through a skylight having a blue/green filter.  
     
     
         20 . A method for treating aging or damaged skin comprising applying directly to affected skin areas light-emitting diodes that irradiate the skin with visible light having a wavelength of about 400 nm to about 500 nm.  
     
     
         21 . A method according to  claim 20  wherein the light-emitting diodes are applied to the skin as skin patches.  
     
     
         22 . A method according to  claim 20  wherein the light-emitting diodes are applied to the skin in a face mask.