Lazy Eye

Dr. Ajay Mohan (AIIMS)MBBS

May 25, 2020

May 25, 2020

Lazy Eye
Lazy Eye

Medically known as amblyopia, lazy eye is a condition that typically develops in early childhood (up to seven years of age).

It occurs when the vision does not develop properly in one of the eyes of a child—the brain favours inputs from the stronger eye, and over time, the weaker eye becomes "lazy" and starts to move inward or outward or without coordination with the stronger eye.

Though rare, it is possible to have two lazy eyes.

It is extremely important to diagnose amblyopia early, otherwise, the child may not be able to develop normal or healthy vision. (Read more: Eye disorders) This is because when the brain starts to favour one eye over the other, it leads to the deterioration of vision in the weaker eye.

Estimates of the number of children affected by this condition range from 3 out of 100 children in the United States, to 1% to 6% of Indian children. An Indian study also suggests a higher incidence of this condition in rural children as compared to children in urban areas, possibly due to a lack of general awareness and facilities for regular check-ups.

Lazy eye symptoms

Lazy eye can be difficult to diagnose, especially during a child’s infancy—this is because babies are unable to focus their eyes on anything beyond a few centimetres for several weeks after birth. Even later, it can be difficult for babies to describe any problems they may be facing with their vision.

Children who are slightly older may be able to explain their problem better—often children with this condition complain of difficulty reading, writing or drawing or while learning music. Although the symptoms of this condition may not manifest physically for a long time, here are some signs one must watch out for:

  • If the baby/child has blurred vision or poor depth perception. (Read more: Myopia)
  • If the baby/child has a squint, where the weaker eye doesn't align with the other eye—it could be pointing in a different direction when the other eye is looking straight in front.
  • If the baby/child frequently tilts their head to look at something.
  • If the baby/child bumps into things on one side a lot more frequently than on the other side.
  • In some rare cases, childhood cataracts are also responsible for amblyopia. If there is cloudiness or a noticeable spot in the child's eye, take him or her to an ophthalmologist for an examination.

Lazy eye causes

Some of the causes of amblyopia include:

  • Cross-eye or strabismus: Strabismus is a condition of misalignment of the eyes. In this case, a child may be unable to look in the same direction with both eyes.
  • Refractive errors: One of the child's eyes may focus better than the other, while the weaker eye may have problems such as blurred vision, myopia (near-sightedness), hyperopia (far-sightedness) or astigmatism, which relates to blurred or distorted vision.
  • Cataract: Some children develop cataract early, a condition where the lens is clouded and prevents clear vision, and is usually common among the elderly.
  • Ptosis: Commonly known as droopy eyes or drooping eyelids, this condition can block the ability of a child to see properly and thus result in the development of amblyopia.
  • Reduced amount of light entering one of the eyes can also lead to complications such as amblyopia.

Amblyopia may start because of a number of reasons, but they all culminate in the same thing: when the brain gets better visuals from one eye, it starts to favour that eye over the other one. Slowly, but steadily, the neural pathways (nerve connection between the eyes and the brain) starts to change to enable this. That's why it is very important to diagnose amblyopia as early as possible and get the appropriate treatment for the child.

Diagnosis of lazy eye

One of the ways to stop the development of amblyopia is to get your child checked for the condition early, preferably before the age of 6. Routine eye tests are often enough to diagnose lazy eye, and the sooner it is done, the better the chances of recovery.

Children should have their eyes tested early in life—in some countries, it is mandatory. It is a good idea to get your child's eyes tested at regular intervals, and at least once before they begin school. Based on the routine optical test, a doctor may advise further tests if they see anything unusual.

Lazy eye treatment

Early diagnosis and treatment, preferably before the child turns 8, is key to stopping the development of lazy eye in children. Early treatment includes the following:

  • Spectacles/contact lenses: Refractive errors of the vision such as myopia, hyperopia or astigmatism can be corrected with glasses or contact lenses. Just the regular use of these accessories can sometimes be enough to solve the problem at hand. In some children, there is a lot of difference in the power in each eye—don't be alarmed by this. Follow your doctor's advice closely.
  • Eye patch: Wearing an eye patch over the strong eye forces the brain to use the weaker eye more. Even though the child may face problems at first, this technique is known to improve vision in the weaker eye—it can take some time though. However, once the problem subsides and the child is able to see equally well from both eyes, he or she may not need the eye patch any more. That said, if the problem comes back, the child may have to again wear a patch.
  • Surgery: A surgical procedure is needed if the child has developed cataract, strabismus which stops the eyes from moving in sync with each other, or even droopy eyelids.
  • Eye drops: Specific medicated eye drops tend to blur the vision in the good eye, again forcing the brain to use the weaker eye more. This doesn't require the child to keep wearing an eye patch, which may be uncomfortable. However, eye drops can also lead to side effects like eye irritation, reddening or headaches.

Lazy eye risks and complications

There are some risk factors that increase the chances of a lazy eye in a child:

  • Being born prematurely
  • If the child is smaller than the average size at birth
  • Being born with developmental disabilities
  • Genetics: If there is a family history of amblyopia or other eye illnesses.

One possible complication of amblyopia is a partial or total loss of vision in the weaker eye, which can become permanent.


  1. National Eye Institute [Internet] Bethesda, MD, USA. Amblyopia (Lazy Eye)
  2. American Academy of Opthalmology [Internet] San Francisco, CA, USA Amblyopia: What Is Lazy Eye?
  3. HealthLinkBC: Government of British Columbia. [Internet] Victoria, British Columbia, Canada. Amblyopia
  4. National Health Service [Internet]. UK; Lazy eye
  5. Kapoor S. Update on Diagnosis and Management of Amblyopia Delhi Journal of Opthalmology. 2019 May; 29:95-97.
  6. Ganekal S et al. Prevalence and Etiology of Amblyopia in Southern India: Results From Screening of School Children Aged 5-15 Years Opthalmic Epidemiology. 2013 Aug;20(4):228-31.

Medicines for Lazy Eye

Medicines listed below are available for Lazy Eye. Please note that you should not take any medicines without doctor consultation. Taking any medicine without doctor's consultation can cause serious problems.