Amblyopia, or lazy eye, occurs when one eye becomes weaker than the other during infancy or childhood. The brain favors the better eye, allowing the weaker eye to get worse over time. Early screening is important because treatment is more effective when started early. Treatments include an eye patch or glasses.

What Is Amblyopia?

Amblyopia, often called lazy eye or lazy vision, is a serious eye condition that affects vision. Poor sight develops in one eye during infancy or childhood and gets worse over time if not treated.

How Does Amblyopia Affect My Child?

In a child with amblyopia, one eye has blurred vision, and the other has clear vision. The brain begins to ignore the blurry eye and uses only the eye with clear vision. Eventually, the brain learns to rely on the stronger eye, allowing the weaker eye to worsen.

Who Is At Risk For Amblyopia?

Some children may have risk factors for amblyopia, including:

  • Family history of eye problems.
  • Developmental disabilities.
  • Born early (premature birth).
  • Small at birth.


What causes amblyopia?

Amblyopia occurs when there is a major difference between the two eyes in their ability to focus. The most common cause of amblyopia is other vision problems. It’s important to treat these other conditions, or the brain starts relying on the eye with better vision, leading to amblyopia.

What Eye Conditions May Lead To Amblyopia?

Conditions that may lead to amblyopia include:
Refractive errors: These conditions affect how light passes through the eye. They include:

  • Nearsightedness (myopia), trouble seeing far away.
  • Farsightedness (hyperopia), trouble seeing up close.
  • Astigmatism, a curved cornea.

Strabismus (crossed eyes): The eyes are meant to move together as a pair, but sometimes they don’t. If one drifts (in, out, up or down), the brain may rely on one eye over the other, leading to amblyopia.

Structural problems: Sometimes, the eye has a structural problem that can lead to amblyopia, including:

  • Cataracts, which cause cloudiness in the lens and blurry vision.
  • Astigmatism.
  • Droopy eyelid.
  • Scar on the cornea.

What Are Some Lazy Eye Symptoms?

Amblyopia is not always obvious. The condition often goes undetected until a child has an eye test. So every child should have early, regular vision screening.

You may notice symptoms. A child with amblyopia may:

  • Bump into things on a particular side a lot.
  • Experience a large difference in nearsightedness or farsightedness between the two eyes.
  • Favor one side of the body.
  • Have crossed eyes.
  • Have a droopy eyelid.
  • Shut one eye or squint a lot.
  • Frequently tilt their head to one side.