The short explanation
Some eye symptoms need emergency care the same day, because treatment within hours can save sight. These include sudden loss or dimming of vision in one or both eyes, a shadow or curtain coming across your vision, a sudden shower of new floaters or flashes of light, a painful red eye with blurred vision, and any injury or chemical splash to the eye. Many other eye problems — itchy or watery eyes, mild redness without pain, a stye — can usually be seen within a few days.
What depends on your situation
The parts of this that change from woman to woman. Uncertainty is stated, not hidden.
- Flashes and a curtain can be signs of retinal detachment. A painful red eye with blurred vision, haloes around lights, headache and vomiting can be acute glaucoma. Sudden vision loss can also come from a problem with blood supply, sometimes linked to stroke. None of these are things to wait out.
- For chemical splashes, rinse the eye with plenty of clean water straight away and keep rinsing while you arrange care.
What this answer cannot determine
The boundary of online education. These need a clinician who can see you.
- This cannot examine your eye or tell you what is causing a symptom. When in doubt about sudden changes, get seen the same day.
Questions for your clinician
Take these with you. You can add any of them to an appointment card.
- What is causing this, and could it affect my sight?
- What should I do if it happens again or gets worse?
- Do I need regular follow-up?
When to seek help
Clinician-approved guidance for this topic. When in doubt, being seen is never the wrong choice.
- Get emergency eye care now — the same day (call 112 or 108, or go to the nearest emergency department or eye hospital) for sudden loss or dimming of vision, a curtain or shadow across your vision, a sudden burst of new floaters or flashes, a painful red eye with blurred vision, an eye injury, or a chemical splash. Sudden vision loss with face drooping, arm weakness or trouble speaking may be a stroke: call 112 immediately.
- See a clinician within days for a red, sticky eye that is not improving, or mild eye pain.
Sources
The evidence this explanation is built on.
- Detached retina (retinal detachment) NHS
- Red eye NHS
- Retinal detachment National Eye Institute (NIH)
Who wrote and reviewed this
Every AskHer answer names its author. A clinically reviewed answer also names the clinician who signed it off — if no clinician is named below, it has not been clinically reviewed.
- Author
- AskHer Editorial (AI-assisted draft) AskHer's editorial team — not an individual clinician Works in English, தமிழ், हिन्दी
- Clinical reviewer
- Nobody yet No clinician has signed this answer off, and no person on the editorial team has read it yet. That is what the “Written with AI assistance” label means. It is queued for an editor to read, and then for a clinician who works in this area. The sources it was drafted against are listed above.
- Review status
- Written with AI assistance — not yet reviewed by a person
- Last reviewed
- Not yet reviewed by a person
- Version
- 1
Correction history
Substantive changes are listed, not quietly edited away.
No corrections have been made since this answer was first published.
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