Symptom guide

Start with what you notice.

Symptoms are the way most people first meet an eye problem. This guide helps you understand what a symptom might mean and how urgent it is.

Medical reviewer Mr Mohamed Mohyudin· Last recorded site review July 6, 2026

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All symptoms A–Z

Blurred visionSudden blurring needs urgent careFuzzy or out-of-focus vision; often a focusing problem, but sudden blurring in one eye needs urgent care.Red eyePainful red eye needs urgent careA red or bloodshot eye; usually harmless, but pain, light sensitivity or vision changes need urgent care.Eye painSevere eye pain is an emergencyAching, sharp or gritty eye pain; some causes are minor, but severe pain with vision changes is an emergency.Itchy eyesUsually not an emergencyItchy, irritated eyes; most often allergy or eyelid irritation, and rarely an emergency.Dry, gritty eyesUsually not an emergencyA dry, gritty or burning feeling; usually dry eye or blepharitis, and manageable with simple care.Flashes and floatersA sudden increase is an emergencySpots that drift and brief flashes of light; often harmless, but a sudden increase is an emergency.Double visionSudden double vision needs urgent careSeeing two images of one object; a new or sudden onset needs prompt assessment.Light sensitivityPain with light sensitivity needs urgent careDiscomfort in bright light; often from surface irritation, but pain with light sensitivity needs urgent care.Watering eyesUsually not an emergencyEyes that water too much; usually minor, from dryness, irritation or blocked tear drainage.Sudden vision lossMedical emergency: seek care nowA sudden drop in vision is a medical emergency and needs immediate eye care.Eye dischargeUsually minor; some signs need urgent careSticky, watery or crusty discharge; usually conjunctivitis or blepharitis, but pain or vision changes need urgent care.Swollen eyelidSpreading redness needs urgent careA puffy or swollen eyelid; usually a stye, chalazion or allergy, but spreading redness needs urgent care.Eye strainUncomfortable but not harmfulTired, achy eyes and headaches after close or screen work; eased by breaks and the right glasses.Halos around lightsSudden painful halos are an emergencyRings or glare around lights; often cataracts, but sudden halos with pain and redness are an emergency.Difficulty seeing at nightGet checked if it is worseningPoor night vision; often cataracts or uncorrected sight, but progressive loss can signal a retinal condition.Cloudy visionSudden clouding needs urgent careHazy or milky vision; often cataracts, but sudden clouding in one eye needs urgent care.Burning eyesUsually not urgent unless the eye is painful and redA hot, stinging feeling in the eyes; usually dry eye or allergy, but a painful red eye needs urgent care.Distorted visionNew distortion needs prompt assessmentStraight lines look wavy or bent; can signal macular disease and needs prompt assessment.Peripheral vision lossSudden side vision loss needs prompt careLosing side vision or feeling like you are looking through a tunnel; can signal glaucoma or retinal disease.Pressure behind the eyePainful pressure with vision changes needs prompt careA fullness or pressure feeling behind or around the eye; often benign but can relate to glaucoma or sinus problems.Feeling of something in the eyeChemical splash or high-speed injury needs urgent careGritty, scratchy sensation as if something is stuck; often dry eye or a foreign body, but persistent feeling needs checking.Yellow eyesYellow sclera may signal jaundice — see a doctorYellowing of the white of the eye; often signals jaundice from liver or gallbladder disease and needs medical assessment.Leukocoria (white pupil reflex)Medical emergency in children: seek care todayA white or pale pupil reflex in a child, especially in photos, is an emergency that needs same-day specialist assessment.Unequal pupils (anisocoria)New anisocoria needs prompt assessmentPupils of different sizes are often harmless if long-standing, but new anisocoria with pain or droopy lid needs urgent care.

Urgent symptoms

Seek same-day or emergency care for these.

Sudden vision loss
New flashes and floaters
A curtain or shadow over vision
Severe eye pain
Eye injury or chemical splash

Common everyday symptoms

Usually less urgent, but still worth understanding.

Dry, gritty or watery eyes
Blurry near or distance vision
Eye strain and headaches
Mild redness or irritation

How we rate urgency

Each symptom guide explains likely causes and gives a clear urgency level, so you know whether to monitor, book an exam, or seek emergency care.

Frequently asked questions

Which eye symptoms are an emergency?

Sudden vision loss, a new shower of floaters or flashing lights, a curtain or shadow over your vision, severe eye pain, or any eye injury need same-day medical care.

Are floaters always serious?

Occasional floaters are common and usually harmless, but a sudden increase, especially with flashes or a shadow, can signal a retinal problem and needs urgent assessment.

Why is my vision suddenly blurry?

Sudden blur has many causes, from dry eye to more serious issues. If it is sudden, persistent, or affects one eye, seek prompt medical advice.

What is the difference between red eye and bloodshot eyes?

They describe the same visible redness, but a painful bloodshot eye with light sensitivity or vision change needs urgent assessment, while mild redness with watering may be conjunctivitis or dry eye.

When should yellow eyes be checked?

Yellowing of the white of the eye (sclera) often signals jaundice from liver or gallbladder disease. See a doctor promptly — this is usually a medical rather than routine optician issue.

Can stress cause eye symptoms?

Stress can worsen dry eye, twitching, and migraine-related visual aura. It does not replace the need to check new vision loss, pain, or flashes urgently.

Should contact lens wearers treat red eyes differently?

Yes. Remove lenses at the first sign of pain, redness, or reduced vision and seek same-day advice. Infections can progress quickly in lens wearers.

What does double vision mean?

Seeing two images can come from eye alignment problems or, if sudden, more serious conditions including stroke. Sudden double vision with weakness or speech changes is an emergency.