What should you know about extreme red eyes?

Redness occurs when small blood vessels on the eye surface widen or become irritated. Allergic conjunctivitis often causes itching and watering, while conjunctivitis can cause discharge, gritty discomfort, and eyelids sticking together. Dryness, smoke, dust, contact lenses, or rubbing can also redden the eyes. Severe pain, reduced vision, halos, strong light sensitivity, or a cloudy-looking eye are not typical of simple irritation and require examination.

Wash your hands, avoid rubbing your eyes, and pause contact lens use until symptoms have settled and a clinician has advised you. A cool clean compress may ease irritation. Do not share towels, pillows, eye makeup, or drops. Avoid using leftover prescription drops, especially steroid drops, because the wrong treatment can worsen some eye problems. Note whether one or both eyes are affected and whether discharge or vision change develops.

Seek urgent eye care for severe pain, sudden vision change, injury or chemical exposure, intense light sensitivity, nausea with eye pain, a fixed or irregular pupil, or a contact-lens-related red eye. Rinse a chemical exposure with clean running water while obtaining urgent help. Arrange review when redness persists, spreads, or has significant discharge.

Ask whether the pattern fits allergic conjunctivitis, conjunctivitis, dryness, or another eye condition; whether you need a swab or eye examination; and when contact lenses can be restarted. Ask which drops are suitable and which warning signs should prompt same-day care.