Amblyopia, often called “lazy eye,” is when one eye doesn’t develop normal vision. The brain favours one eye over the other, suppressing the vision in the weaker eye. This condition is common in children, but it can also affect adults. It can be treated effectively if caught early. Amblyopia has a 2-3% prevalence in children worldwide. A child’s vision develops in the first few years of his life. Early detection and treating the underlying cause can help improve vision. If untreated, it can lead to permanent decreased vision in the affected eye.

This fact sheet is part of our Ophthalmology and Optometry Information Guide series, developed to help people understand eye conditions and their impact on navigating the built environment.