Double vision (diplopia) is not usually serious, but it's important to get it checked, even if it comes and goes.

Double vision is when you look at 1 object but can see 2 images. It may affect 1 eye or both eyes.

Children often cannot tell if they have double vision. Signs that your child may have problems with their vision include:

• narrowing or squinting their eyes to try to see better
• closing 1 eye or covering 1 eye with their hand
• turning their head in unusual ways (for example, tilting their head)
• looking at you sideways instead of facing forward

Go to an optician or see a GP if:

If you have double vison, an optician or GP can ask about your symptoms and do some simple, painless eye tests.

They may refer you to an eye specialist in hospital for tests and treatment.

The optician can also let you know if you need to see a GP instead.

Ask for an urgent GP appointment or get help from NHS 111 if:

Call 999 or go to A&E if:

Your eyecare team or GP can advise you about the best treatment for double vision once they work out the cause.

In some cases, this may be simple treatments such as eye exercises, wearing an eye patch or being prescribed glasses or contact lenses.

Some conditions that cause double vision may require eye surgery to correct the problem.

Double vision has many possible causes, depending on whether 1 eye or both eyes are affected.

Try covering 1 eye at a time to see if your double vision goes away.

If your double vision goes away with 1 eye covered, it's probably affecting both eyes (binocular).

If you still have double vision in the eye that is not covered, it's probably only affecting that eye (monocular).

Double vision affecting both eyes is usually a symptom of a squint.

This is where problems with the eye muscles or nerves cause the eyes to look in slightly different directions.

Squints are more common in children, but they do not always cause double vision. An untreated squint in children under 7 causes a lazy eye instead.

Squints or binocular double vision in adults can be a sign of a more serious condition.

Double vision affecting 1 eye (monocular)

Double vision affecting 1 eye is less common. It's usually caused by eye problems such as:

• dry eyes – where the eyes do not produce enough tears
• astigmatism – a common condition where part of the eye is not a perfect shape
• cataracts – cloudy patches over the front of the eyes
• keratoconus – where the clear outer layer of the eye (cornea) gets thinner and changes shape

Important

You must stop driving and tell the Driver and Vehicle Licensing Agency (DVLA) if you're diagnosed with double vision. You can drive again if a doctor tells the DVLA it's safe for you to do so.

Find out how to tell the DVLA about double vision (diplopia)