MINNEAPOLIS (WCCO) — Those cosmetic contacts that some wear on Halloween to create a spooky theme are actually a prescription for problems, according to a Twin Cities doctor and the Food and Drug Administration.

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“It is not safe,” said Dr. Aaron Nathenson, an ophthalmologist at Hennepin County Medical Center in Minneapolis. “These are dispensed like you buy a blouse or pair of shoes without general concern for the eye.”

He said that medical problems from cosmetic contacts are really magnified this time of year, though he sees some patients all year long.

Every eye is different, so contacts must be fitted properly. Cosmetic contacts are made overseas, and they’re one size fits all. They’re sold over-the-counter and at Halloween stores.

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Pictures of one patient’s eye – in the video above — will put the warning in perspective. They show the damage a patient suffered in the left eye that ended up causing an inflammatory reaction in her right eye. She lost eyesight.

Other medical problems include infection, allergic reactions, like watery eyes, scratching the eyeball and decreased vision.

“The eye is a very sensitive organ and a very vital organ to life,” Nathenson said. “And you have to treat it with quite a bit of respect.”

He said that the problems are numerous with cosmetic contacts. For one, not enough oxygen gets to the eye when you wear them.

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Nathenson says that you can prevent problems by only wearing contacts a doctor prescribes.