Corneal Ulcers and Contact Lenses: Why Sleeping in Them Is Risky contact lens · contact lens care · corneal ulcer · eye infection · keratitis · red eye · sleeping in contacts · Oct 12, 2026 A corneal ulcer is an infection on the clear front of the eye, and sleeping in contact lenses is the biggest risk. Here are the warning signs, what to do right away and how to protect your eyes.