Have you been eyeing those neon-green sunburst eye contacts this Halloween? Beware! While those colored contacts seem like the perfect touch to your homemade zombie costume, they can damage your eyes.

The FDA issued a warning  that buying these decorative contacts from anyone but a licensed ophthalmologist or optometrist can give your eyes a monster mash of problems: scratches on your cornea, infection (including pink eye) and, in the most severe cases, blindness.

These lenses, often sold in pop-up Halloween stores, beauty supply shops and on the Internet, don’t correct your vision but just change the eyes’ appearance. Is it worth risking your eyes’ health for a night of Halloween mischief?

Think of it this way: A recent Internet search showed several websites selling non-prescription colored lenses for $12 to $43. But the American Optometric Association estimates that treating an eye infection, including the cost of prescription medicine and consultations with your eye doctor, can cost hundreds of dollars.

Now that’s something to be afraid of.