About colour blindness

Colour blindness is when people see some colours differently from the way that other people see them. In particular, people with colour blindness see less variety in or fewer differences between colours.

Red-green colour blindness is the most common type. This is when people have trouble telling the difference between some greens, browns, reds and oranges. But colour-blind people can still usually see bright colours like traffic lights and primary colours.

Blue-yellow colour blindness is when people have trouble telling the difference between blues and yellows. This type of colour blindness is rare.

Nearly all children with colour blindness are boys. About 8% of boys have red-green colour blindness. Boys usually inherit colour blindness from their mother’s side of the family.

Symptoms of colour blindness

If your child has colour blindness, they might have trouble telling the difference between some reds, greens, browns and oranges after about the age of 4 years. Your child might say that 2 different colours are the same, or they might struggle to separate things according to colour.

Colour blindness might become obvious at preschool or school, especially when your child is doing activities like sorting blocks, colouring, or copying text of different colours.

Although children with colour blindness confuse some colours, their vision is usually clear.

Colour blindness stays the same over time. It doesn’t get worse or better.

Medical help: when to get it for children with colour blindness

If you think your child might be colour blind, see your GP or optometrist. They might refer your child to an ophthalmologist for testing.

If there are other people in the family with colour blindness, it might be a good idea to have your child tested. You can discuss this option with your GP or optometrist.

Treatment for colour blindness

There’s no cure or treatment for colour blindness. But it might help to know that colour blindness causes very few difficulties in the day-to-day lives of people who have it.

If your child is colour blind, it’s a good idea to let your child’s teachers know. The teachers can choose learning activities that don’t involve spotting colour differences.

As children with severe colour blindness get older, it might be unsafe or hard for them to do jobs where colour identification is important – for example, handling electrical wires or telling warning lights apart. If your child is interested in these sorts of occupations, they might need detailed colour vision testing and careers advice.

Causes of colour blindness

Cone cells in our retinas help us see differences between colours.

There are 3 types of cone cells. Each type responds to a different colour – red, green and blue.

In a person who is colour blind, 1 or more of the 3 cone cell types doesn’t work properly.