For anybody who finds the idea of colored contact lenses appealing, it needs to be noted that to wear them, there is a requirement to obtain a valid prescription from an optician, whether that is for visual correction, or simply for cosmetic purposes.
Colored prescription contacts ensure that individual specifications are met and consequently, health and safety standards are maintained. Lenses, whether colored or normal, should never be shared, for several reasons, possibly the most crucial being that bacteria can be spread to other wearers, leading to some very nasty eye infections, meaning that the risk is just as high upon their return. Conditions experienced include: conjunctivitis, blurred vision, eye ulcers, scratches on the cornea and in really extreme cases, blindness.
Wearing colored lenses can be a great way of enhancing, or completely altering, an individuals look; but it should never be undertaken at the expense of long-term eye health. Prescribed contacts are the only way to guarantee peace of mind.