Coloured contact lenses should be cleaned, used and selected with the same care as if they were being used for vision correction, an expert advises.
Optometrist Bruce Hinkley told the Modesto Bee improper use can damage the eye, so people should be careful if intending to use them for costume fun over the party season.
He warned the use of contact lenses could introduce germs into the eye and cause infection.
However, all reputable contact lens manufacturers promote good hygiene and lens storage practices - for example, always washing hands, always removing contact lenses before sleep, not sharing them with other people.
"Prescription decorative lenses are manufactured by legitimate firms, some of which make them for theatrical companies," the article noted.
Coloured contact lenses lenses for 30-day wear are sold online and can be made for eyes that do not need correction and eyes that do.
The effects produced by the lenses can be subtly enhancing or wild and wonderful.
by Martin Burns