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HealthInfo Waitaha Canterbury

Sudden vision loss in one eye

Te kāpōtanga ki te karu kotahi


Loss of vision in one eye is an emergency. It can be caused by a blocked artery, which can be reversed if it's treated promptly, saving your vision in that eye.

If you've lost vision suddenly, even if it's just been temporary and has now recovered, you must seek medical help from your general practice team or optometrist.

vision loss one eyeYou can lose vision in one eye for several reasons, some of which are potentially serious.

The vision loss can be temporary and may only last a few minutes, but the causes may still be important and need treating.

Unless you regularly lose vision temporarily during migraines, get your eyes checked straight away.

Causes of sudden vision loss in one eye

A blocked blood vessel

A common cause is a blood clot or a piece of plaque blocking an artery in your eye. Plaque is a hard substance that forms when fat, cholesterol and other substances build up in the walls of arteries.

This is called a transient ischaemic attack (TIA). A TIA of the eye has a special name, amaurosis fugax. It's usually painless but it's serious as it means you're at more risk of having a stroke.

Giant cell arteritis

If you're aged over 50 and are also having headaches or scalp or jaw pain (for example, when you're chewing food), this could be because of giant cell arteritis. This is an inflammatory problem that affects blood vessels.


Your vision loss is probably caused by a migraine if:

Treating sudden vision loss in one eye

This will depend on the cause of the vision loss. The sooner you go to your general practice team or optometrist, the better the chance of the treatment being successful whatever the underlying problem.

Written by HealthInfo clinical advisers. Last reviewed March 2023.


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Review key: HIVOE-263981