Though conjunctivitis (inflammation of the conjunctiva) is the most common cause of eye redness and discharge, multiple conditions can cause red or pink eyes, including the following:
• Blepharitis, when your eyelids are irritated and inflamed
• Stye (hordeolum), when you have a painful lump on the eyelid
• Subconjunctival hemorrhage, when a strain like a violent sneeze causes broken blood vessels in the eye
• Corneal abrasion, when the surface of the cornea experiences a trauma like a scratch
• Contact lens overwear, which can cause dryness or abrasions
If you sense a foreign body in your eye, can't keep your eye open, have had recent eye trauma, experience vision changes, develop light sensitivity, or feel serious eye pain, you'll need to see a trusted healthcare provider like an opthalmologist (eye doctor) or an urgent care clinician for an in-person evaluation as soon as possible.