Eye Redness

Brief summary: Eye redness is often caused by conjunctivitis, dryness, irritation, or a small subconjunctival hemorrhage. However, painful redness, light sensitivity, vision change, trauma, or redness in a contact lens wearer may also signal urgent ophthalmic problems. ^[1][2][3]

What does eye redness include?

Eye redness refers to visible redness affecting the white part of the eye or its surface tissues. It may involve one eye or both, and its significance depends heavily on the presence of pain, discharge, visual symptoms, light sensitivity, and contact lens use. Not every red eye is the same. ^[1][2][4]

What are the most common causes?

Many cases are related to viral or allergic conjunctivitis, eye dryness, smoke or dust exposure, or subconjunctival hemorrhage. These conditions often produce itching, tearing, mild irritation, or crusting and are frequently bilateral. Still, appearance alone is not always enough to safely rule out more serious disease. ^[1][2][3]

Which causes are more serious?

Corneal disease, keratitis, uveitis, acute angle-closure glaucoma, trauma, or chemical exposure may all produce a red eye with much greater urgency. Pain, marked light sensitivity, decreased vision, headache, nausea, or unilateral severity are especially concerning features. In contact lens users, red eye must be interpreted more cautiously because of the risk of corneal infection. ^[2][3][4]

How is eye redness evaluated?

Evaluation focuses on whether one or both eyes are affected, whether discharge is watery or sticky, whether the symptom started suddenly, whether trauma or chemical exposure occurred, and whether vision has changed. A basic eye examination, including visual acuity and corneal assessment, is central because the main question is not simply whether redness exists, but which structure of the eye may be involved. ^[1][2][3]

When is urgent evaluation needed?

Urgent ophthalmic evaluation is needed when redness occurs together with decreased vision, significant pain, inability to tolerate light, trauma, chemical exposure, or worsening in a contact lens wearer. These findings may point to vision-threatening conditions. ^[2][3][4]