Color Blindness

(Color Vision Problem; Color Vision Deficiency)


Color blindness is a problem seeing colors the same way as most people.


The most common cause of color blindness is a faulty gene that is passed from mother to son. Other causes are:

  • Eye diseases, such as glaucoma or macular degeneration
  • Brain and nervous system problems, such as Alzheimer disease or multiple sclerosis
  • Some medicines, such as hydroxychloroquine
  • Eye or brain injuries
  • The normal aging process

Anatomy of the Eye

Normal Anatomy of the Eye
Copyright © Nucleus Medical Media, Inc.

Risk Factors

Color blindness is more common in men and people who are White. The risk is also higher in people who have any of the health problems that cause color blindness. Other things that raise the risk are:

  • A family history of color blindness
  • Taking medicine that can harm the eye, such as hydroxychloroquine


Some people do not know they are color blind. Symptoms may be problems seeing:

  • The difference between some colors
  • The brightness of some colors
  • Different shades of colors


You will be asked about your symptoms and health history. An eye exam and vision test will be done. You may need to see a doctor to confirm the diagnosis.


There is no cure for people who are color blind due to their family history. Most people learn ways to tell the difference between colors.

Some people may be able to get back their color vision when their medical problem is treated or their medicine is changed.

Some tools that may help people with everyday tasks are:

  • Color-corrective glasses or contact lenses
  • Mobile device apps that can show differences between colors and some shades of color


There are no known steps to prevent color blindness.


American Academy of Ophthalmology
Howard Hughes Medical Institute


Canadian Association of Optometrists
Canadian Ophthalmological Society


Color blindness. National Eye Institute website. Available at: Updated July 2019. Accessed October 22, 2019.
Colour blindness. Colour Blind Awareness website. Available at:
...(Click grey area to select URL)
Accessed October 22, 2019.
Hydroxychloroquine. EBSCO DynaMed website. Available at: . Accessed October 22, 2019.
What is color blindness? American Academy of Ophthalmology website. Available at:
...(Click grey area to select URL)
Updated September 6, 2019. Accessed October 22, 2019.
Last reviewed September 2019 by EBSCO Medical Review Board Daniel A. Ostrovsky, MD
Last Updated: 07/10/2020

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