FRIDAY, Oct. 31 (HealthDay News) -- This Halloween, don't put anything in your eye unless it has been prescribed by an eye doctor.

That's the warning from the American Optometric Association (AOA), which is concerned about people wearing decorative contact lenses to enhance their costumes.

While the U.S. Food and Drug Administration regulates decorative lenses as a medical device, some of these products are illegally marketed and distributed directly to consumers through the Internet, beauty salons and other sources. The AOA warns that only a proper medical evaluation from an eye doctor can determine whether someone is a candidate for contact lenses and that the lenses fit properly.

"Purchasing contact lenses without a prescription can result in serious eye health and vision damage, since consumers are not properly educated on cleaning and disinfecting, nor in proper removal and application of the contact lens," Dr. Paul Klein, chairman of the AOAs Contact Lens and Cornea Section, said in a news release from the organization. "Without a prescription and wearing instructions from an eye doctor, consumers who wear these contact lenses put themselves at risk of serious bacterial infection, or even significant damage to the eye's ability to function, with the potential for irreversible sight loss."

Risks associated with the use of decorative contact lenses include conjunctivitis, swelling, allergic reaction and corneal abrasion due to poor lens fit. This could result in several types of eye problems and vision impairments.

"Even though they carry no prescription and may be worn for short periods of time, decorative contact lenses carry the same risks as corrective contact lenses," Klein said. "Because of this, it's important for consumers utilizing these lenses to familiarize themselves with the information available from an eye doctor, so as to reduce the risk of infection."

More information

The American Optometric Association has more about eye and vision problems.