NHS website

Floaters and flashes in the eyes

Floaters are small shapes that some people see floating in their field of vision.

11 October 2018


Dots and lines (floaters) or flashes of light in the eyes are common. They're not usually serious.

Floaters and flashes are usually harmless

If you sometimes see:

  • floaters – such as small dark dots, squiggly lines, rings or cobwebs
  • flashes of light

in your vision, it's not usually a sign of anything serious. Especially if:

  • you've had them for a long time
  • they're not getting worse
  • your vision isn't affected

Flashes may stop by themselves, and floaters often become less noticeable as you get used to them.

Get an urgent optician appointment if:

  • floaters or flashes appear suddenly
  • floaters or flashes suddenly increase in number
  • you have a dark "curtain" or shadow moving across your vision
  • you also have blurred vision
  • you also have eye pain
  • floaters start after eye surgery or an eye injury

These could be signs of a serious problem with the back of your eye, which could permanently affect your vision if it's not treated quickly.

Find an opticians ↗

If you can't get an urgent appointment:

Go to A&E or call NHS 111 straight away for advice.

What happens at your appointment

Your eyes will be checked to see if you might need to be seen by an eye doctor (ophthalmologist) for more tests or treatment.

You'll usually only need treatment if you have a problem that could affect your vision.

Causes of floaters and flashes

Lots of people, particularly older people, get floaters and flashes.

They're usually caused by a harmless process called posterior vitreous detachment (PVD) ↗, which happens as you get older.

Sometimes they can be caused by retinal detachment ↗. This is a serious condition where a thin layer that sends signals to the brain (the retina) pulls away from the back of the eye. It can lead to permanent vision loss if not treated.

Floaters and flashes can also happen for no obvious reason.