Red Eye: Pink Eye, Allergies, or Something More Serious? conjunctivitis · eye allergies · pink eye · red eye · subconjunctival hemorrhage · Oct 14, 2026 Most red eyes come from something common, like pink eye, allergies, dry eye or a broken blood vessel. A red eye with pain, light sensitivity or blurry vision needs to be seen the same day. Here is how to tell the difference.