The lenses, which can change your eyes to a different color or to look like an animal’s eyes, are illegal to buy without a prescription.
Several federal agencies, including the Food and Drug Administration, have started “Operation Double Vision” to seize the illegal contact lenses from store shelves.
Authorities are warning consumers not to buy contact lenses from Halloween or novelty shops, salons, beauty supply stores or online if the they don’t require a prescription.
Health officials say the illegal contact lenses can cause eye infections, including redness, lasting eye pain or even decreased vision.
If you’re interested in getting decorative lenses for a Halloween costume, officials recommend getting them from an authorized eye doctor.