Amblyopia (lazy eye)

Lazy eye or amblyopia may be caused if a young child needs very strong glasses, has one eye that is significantly more short-sighted or long-sighted than the other, or has a squint (where the eyes are not looking in the same direction). This means that the sight in the affected eye or eyes does not develop properly.

Who is affected by amblyopia (lazy eye)?

About 2%-3% of all children develop lazy eye, clinically known as amblyopia, when they are a few years old. Children with learning difficulties are ten times more likely to have problems with their vision, including amblyopia

What are the symptoms of amblyopia (lazy eye)?

Lazy eye is not always easy for parents to spot, and children assume that the way they see is normal and so will not tell you that there is a problem. Symptoms include:

• one eye turning in or out. This may be more noticeable if the child is tired or unwell
• being clumsy or having poor hand to eye coordination
• screwing up their eyes or shutting an eye
• complaining about double vision or having unexplained headaches.

The NHS recommends that all children should have vision screening during their first year at school. This is done in school, usually by a school nurse, and should pick up vision problems including amblyopia.

If you have any concerns about your child’s eyes or vision you should take them to see your optometrist at any age but if you don’t have any concerns, we recommend that you take your child for their first sight test when they are around 3-4 years old. Children should be seen regularly, around 1-2 or as advised by their optometrist.

How do you treat amblyopia (lazy eye)?

The aim of treatment is to stimulate the vision to develop in the lazy eye by enabling the child to use the eye more. The treatment depends on what is causing the lazy eye:

• wearing glasses – if the cause of the amblyopia is fully corrected by glasses, the vision in the amblyopic eye may improve over time simply by the child wearing glasses, and no further treatment is needed
• patching – covering your child’s good eye can encourage them to use the lazy eye, and so improve vision in that eye
• eye drops – these are put into the good eye to blur the vision in that eye. They act like patching.
• surgery – if glasses do not fully correct a child’s squint, the child may need an operation to straighten their eyes to help them use both together. This can be done as early as a few months of age.

It is more difficult to treat lazy eye once the eyesight has finished developing (usually around the age of seven), which is why it is important to take your child for a sight test early. It may still be possible to improve the vision in the weaker eye after this time but the earlier amblyopia is detected, the easier it is to treat.

Amblyopia advice, information and support

British and Irish Orthoptic Society

Last updated: April 2025

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