Red painful eye: what to know

Pain may come from a scratched surface, a foreign body, dryness, inflammation or infection. [Conjunctivitis](/conditions/conjunctivitis/) often causes redness, watering or discharge, while [Allergic Conjunctivitis](/conditions/allergic-conjunctivitis/) more often brings itching and usually affects both eyes. Severe pain, light sensitivity, reduced sight or a feeling that something is stuck changes the level of concern.

Contact lenses, recent eye injury, chemical exposure and recent eye surgery are especially relevant details. The amount of redness does not reliably show how serious the cause is. A clinician may examine the surface of the eye and check vision before recommending treatment.

Do not rub the eye, attempt to remove an embedded object, or use leftover antibiotic or steroid drops. Remove contact lenses and keep them out until a clinician says otherwise. If a loose irritant is present, rinse with clean lukewarm water; after a chemical splash, rinse continuously while seeking emergency help.

Use sunglasses if ordinary light is uncomfortable, and take the lens case and all eye medicines to an appointment. The [Red Eye](/symptoms/red-eye/) information can help you describe discharge, watering, itch and the timing of symptoms.

Get urgent assessment for severe or increasing pain, blurred or reduced vision, strong light sensitivity, a visible foreign body, injury, chemical exposure, marked swelling, or a red eye in a contact-lens wearer. Sudden loss of sight, a penetrating injury or severe headache with nausea requires emergency care. Prompt assessment matters even when the eye looks only mildly red.

Ask: Is the cornea involved? Could my contact lenses or an injury explain this? Which drops are suitable? When can I safely return to lenses, work or driving?