What should you know about painless red eye?

Redness can come from irritation, dryness, allergy, a small surface blood vessel or conjunctivitis. Allergic Conjunctivitis often brings itching and watering, while Conjunctivitis may cause discharge and eyelids sticking together. A sharply defined red patch can follow minor irritation or straining. Painless does not always mean harmless, especially if vision changes or the redness spreads.

Note whether one or both eyes are affected, whether there is discharge, itching, light sensitivity, swelling or a recent injury. Contact lens wear is also relevant because it can change the urgency of eye symptoms.

Do not rub the eye. Wash your hands, avoid sharing towels, pause contact lenses and eye make-up, and use a clean cool compress for irritation. Clean discharge gently with fresh cotton or a clean cloth for each eye. Avoid using leftover prescription drops; a pharmacist or clinician can advise which products are appropriate.

Seek urgent eye care for any vision loss or change, significant light sensitivity, severe pain, injury or chemical exposure, marked swelling, or difficulty moving the eye. Contact a clinician promptly if you wear contact lenses and develop redness, if discharge is heavy, or if the redness is worsening or not settling.

What is the likely source of the redness? Do I need a swab, examination or treatment? When can I safely resume contact lenses, and which warning signs should prompt urgent eye care?