Symptom

Red eye

Other ways people describe this: bloodshot eye · eye redness

Painful red eye needs urgent care

Medical reviewer Mr Mohamed Mohyudin, Consultant Ophthalmic SurgeonArticle reviewed

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When to get urgent help

  • A red eye with moderate or severe eye pain
  • Sensitivity to light or changes in your vision
  • A red eye after an injury or chemical splash
  • Intense redness with a headache, nausea or halos around lights

Common causes

Most red eyes are harmless. These are common causes, with the conditions to read about next.

ConjunctivitisOverview of pink eye — read viral, bacterial or allergic pages for your pattern.Viral conjunctivitisWatery red eye, often after a cold; very contagious.Bacterial conjunctivitisSticky yellow-green discharge, lids glued on waking.Eye allergiesItchy, watery eyes in both eyes with hay-fever symptoms.Dry eyeRed, gritty, tired eyes that may also water.BlepharitisRed, crusty eyelid margins and sore eyes.Subconjunctival haemorrhageA painless bright red patch from a burst vessel.StyeA red, tender lump on the eyelid.UveitisA painful red eye with light sensitivity that needs prompt care.Corneal abrasion (scratched eye)A painful red eye after a scratch or foreign body.Acanthamoeba keratitisSevere pain with lens wear or water exposure; needs same-day care.

Types of pink eye

Viral conjunctivitisVery contagious watery pink eye, often after a cold; antibiotics do not help — hygiene and time are the main treatment.Bacterial conjunctivitisSticky yellow-green discharge and glued lids, often needing antibiotic drops after assessment; more urgent in babies and contact-lens wearers.Eye allergiesItchy, red, watery eyes from pollen, dust or pets; seasonal peaks in spring and summer respond well to trigger avoidance and allergy drops.

What can help

  • Lubricating drops can ease redness from dryness or irritation
  • Gentle eyelid cleaning helps blepharitis and styes
  • See a clinician urgently if the eye is painful or vision changes

Frequently asked questions

When should I worry about a red eye?

Seek urgent care if a red eye comes with pain, light sensitivity, changes in vision, or follows an injury or chemical splash, as these can signal a more serious problem.

Is a red eye always conjunctivitis?

No. Conjunctivitis is common, but red eyes can also come from dry eye, blepharitis, a harmless burst blood vessel, or more serious causes such as uveitis.

How long does a red eye last?

Minor causes often settle within one to two weeks. A red eye that is painful, affects vision, or does not improve should be assessed.

Which pink eye type do I have?

Itch in both eyes with hay fever suggests allergy. Thick pus and glued lids suggest bacterial. Watery redness after a cold suggests viral. Read the matching conjunctivitis page for full guidance.

Is a bloodshot eye the same as pink eye?

Pink eye usually means conjunctivitis, but bloodshot eyes can also be dry eye, a burst vessel, blepharitis or more serious inflammation — pain or vision change needs assessment.

Your next step

Take this to your appointment

Write down what has changed, when it started, your current medicines and the questions you want answered. Take these to your eye-care appointment.

Patient resourcesFind care where you live →

Sudden loss of sight, severe eye pain or a dark curtain across vision needs immediate assessment. Do not wait to complete a worksheet.

Trusted sources

For general background, these organisations provide eye-health information. This list is further reading, not a record that they reviewed this article.

Sources and evidence →