As a treatment for toenail fungus uv light is seldom, if ever used. However, it can be useful as a means of ridding the environment of infectious fungal spores. Laboratories that work with fungal isolates use ultraviolet light to sterilize equipment, and it has been at least suggested that ultraviolet light might prevent fungal spores and other organism from being dispersed through air conditioning and ventilation systems. At home, simply exposing shoes and socks to normal daylight, which includes ultraviolet wavelengths, may help kill off lingering fungal elements from fungal nail infections.
Ultraviolet light is harmful or lethal to many forms of life. It is routinely used to disinfect contaminated surfaces and water supplies. On the other hand, exposure to ultraviolet rays causes blindness, and almost everyone is aware that increased exposure to ultraviolet in sunlight is causing an increase in skin cancers. It is not a benign light, therefore any toenail fungus uv treatment should be approached with extreme caution, and under the supervision of a professional. Tanning beds are a relatively safe way to expose skin and nails to ultraviolet light, but even these come with associated risks and many people do not think they are a safe approach to tanning or skin treatment.
Perhaps the reason some people believe that toenail fungus uv treatment is an option is that patients who suffer from psoriasis are often treated with ultraviolet radiation. This can be very beneficial in clearing up the uncomfortable skin lesions these individuals suffer experience. Because psoriasis patients often have deformed nails that resemble nails that are infected with fungus, there may be some confusion: dermatitis caused by psoriasis affects the root of the nail and makes the nail grow out abnormally: settling down the dermatitis can result in new nail growing in with a normal appearance. Clearly, this is not a toenail fungus uv cure.
One of the drawbacks in ultraviolet light, with respect to sterilization techniques at least, is its inability to penetrate surfaces. Glass and plastic that don't allow ultraviolet wavelengths to pass through are readily created. It may very well be that ultraviolet rays would not penetrate an infected nail sufficiently to affect the fungus growing underneath – a weakness of many nail fungus treatments. The bottom line is that toenail fungus uv treatment is not a good treatment choice. A natural remedy or prescription drug will probably work better and carry less risk.