The FDA is warning against decorative contact lenses. The agency is especially concerned about companies that sell the lenses without a prescription.

FDA officials are concerned that the lenses could cause serious damage. The lenses are called Plano or non corrective lenses and they're worn strictly for looks.

The lenses could cause permanent eye injury that could lead to blindness. Other risks include conjunctivitis (pink eye), corneal ulcers, corneal abrasion and vision impairment. Sharing lenses is particularly dangerous, leading to infections, abrasions, allergic reactions and even blindness.

The lenses are being sold in beauty salons, flea markets, convenience stores and over the Internet. Last year, the Food, Drug and Cosmetic Act was amended to include all contact lenses under the FDA's control.

The FDA said it would pursue those who sell or distribute the lenses improperly. Any distribution of the lenses without the involvement of an eye care professional will be considered illegal.