---
title: What causes sudden blindness in one eye?
description: "Sudden blindness or severe vision loss in one eye is a medical emergency. Several sight-threatening conditions can cause it. ## Vascular and retinal causes Blocked blood vessels at the retina or optic nerve stop oxygen reaching vital tissues. Vision may…"
url: "https://bluefinvision.com/knowledge-base/topics/symptoms-signs/what-causes-sudden-blindness-in-one-eye/"
updated: "2025-12-31"
category: "Symptoms & Signs"
---

# What causes sudden blindness in one eye?

Sudden blindness or severe vision loss in one eye is a medical emergency. Several sight-threatening conditions can cause it.

## Vascular and retinal causes

Blocked blood vessels at the retina or optic nerve stop oxygen reaching vital tissues. Vision may go dark or very blurred within seconds.

- Central retinal artery occlusion often causes profound, painless loss
- Central retinal vein occlusion may cause sudden, hazy vision
- Retinal detachment can produce rapid loss with floaters and flashes
- Eye strokes are linked with cardiovascular risk factors

## Other urgent causes

Severe optic nerve inflammation, acute glaucoma, or trauma can also lead to sudden blindness. Fast treatment offers the best chance of recovery.

- Optic neuritis may cause pain on eye movements and colour desaturation
- Acute angle-closure glaucoma causes intense pain, haloes, and nausea
- Penetrating injuries can instantly destroy retinal function
- Emergency hospital assessment should never be delayed