Color blindness is the reduced ability to distinguish colors or to see color. This condition affects about one in 200 women and one in 12 men worldwide. Most people with color blindness can see things as well as ordinary people. But, they are unable to differentiate colors, especially red, blue, or green.

In the case of inherited color blindness, one may be born with it or it may manifest in childhood or later in life. Its effects can be mild, moderate, or severe depending on the defect or mutation. The disorder usually affects both eyes and can remain stable throughout a person’s life. It can also be progressive involving the retina and other sections of the eye. It is important to realize that a change in color vision may signify a more serious condition. A person who experiences a change in distinguishing color should see an eye care professional.

Also Known As

  • Color vision deficiency
  • CVD


Color blindness can be inherited or acquired. 
Inherited color vision deficiency is classified into: 

  • Blue-yellow color blindness
  • Red-green color blindness
  • Total color blindness

Causes and Risk Factors

Color blindness is as a result of abnormal photopigments in the cone cells of the retina. It is often an inherited genetic disorder.

Most people with color blindness inherited the disorder from their mothers who are carriers of the defective X chromosome that causes it. It is the main reason why the condition affects more men than women.
Age and chronic diseases such as diabetes, liver disease, multiple sclerosis, and eye diseases can also cause color blindness.
Other causes include accidents, traumas, pollution, and toxic effects from drugs.

Signs & Symptoms

Symptoms of the eye disorder can range from mild to severe. Often the symptoms are very mild and many people are unaware they are color blind. The symptoms include:

  • Inability to see colors in the usual way
  • Difficulty in differentiating color shades 


Pseudoisochromatic tests help eye care professionals to diagnose color blindness. The tests can diagnose specific kinds of color vision deficiency.


Treatment aims at improving patients’ ability to distinguish colors and shades.

Medical Treatment

Medical treatment for the condition involves use of colored filters or contact lenses. They help increase brightness and make it easier for the patient to differentiate colors. Eye doctors can treat acquired forms of color vision deficiency. They identify and address the underlying health problems or side effects of medication that caused the condition.

Home Care

People with color blindness learn to adapt to the condition. There are several ways an individual can compensate for their difficulty in seeing colors. One way would be to ensure lighting in the work environment and at home is adequate and of good quality. This helps to distinguish colors. 
In case of severe color vision deficiency, a person can ask family members or friends for help. Parents can inform teachers of the condition so that teaching methods and learning material be modified.

Alternative Treatment

There are mobile applications that help color blind people to see colors in a better way. These online treatments don’t cure the disease. They may only help color blind people in distinguishing between colors and shades.

Prognosis/Long-term outlook

Congenital color blindness is present in both eyes. It remains constant over the entire person’s life without any significant disability. In some cases if the underlying cause is removed, acquired color blindness may improve with time. But in most people, the damage is permanent.

Prevention/Follow Up

Inherited color blindness is not preventable. Neither is color vision deficiency associated with chronic diseases. Early detection of the disorder in children is essential. Doctors can then understand its nature and severity. 

Some types of acquired color blindness are preventable. Reducing alcohol intake and proper use of medication may limit acquired color blindness. It is vital to go to regular eye checks for conditions that may result in color blindness. Eating a healthy diet is also essential.