Flashes, Floaters and Sudden Vision Loss: When an Eye Problem Is an Emergency

Most eye complaints are minor and can wait for a routine visit. But a small number are emergencies, where getting seen quickly can mean the difference between saving and losing vision. It’s worth knowing which is which.

Floaters and flashes — usually harmless, sometimes not

Floaters — those little specks or cobwebs that drift across your vision — are extremely common and usually harmless, caused by normal changes in the jelly inside the eye. Occasional flashes of light can be normal too.

But pay urgent attention if you notice:

• A sudden shower of new floaters, especially with flashes of light
• A dark curtain or shadow spreading across part of your vision
• A sudden loss of side vision

These can be signs of a retinal tear or detachment — a condition where the retina is pulling away from the back of the eye. Treated early (often within hours to days), the outlook is good. Left too long, it can cause permanent loss.

Other symptoms that shouldn’t wait

• Sudden, painless loss of vision in one eye
• Sudden severe eye pain with redness, haloes and nausea (possible acute glaucoma)
• A chemical splash or significant eye injury
• Sudden double vision or a drooping eyelid with pain
• Any red, painful eye in a contact lens wearer — remove the lens and get seen

The simple rule

Gradual changes usually allow time for a routine appointment. Sudden changes — in vision, with pain, or a new curtain/flashes/floaters — deserve urgent attention, the same day.

When in doubt, it’s always safer to call and ask. You can reach our team via our contact page, and read about our retina services here.

With the eye, gradual is usually patient; sudden is usually urgent. When something changes fast, don’t wait it out.

This article is general information, not a substitute for a personal consultation. If you have sudden eye symptoms, please seek care promptly.