Skip to main content
N I Direct government services

Main navigation

  • Home
  • News
  • Contacts
  • Help
  • Twitter
  • Facebook
  • YouTube
  • RSS

Translation help

Translate this page

Select a language

  • Afrikaans — Afrikaans
  • Albanian — Shqip
  • Amharic — አማርኛ
  • Arabic — العربية
  • Armenian — Հայերեն
  • Assamese — অসমীয়া
  • Aymara — Aymar aru
  • Azerbaijani — Azərbaycan dili
  • Bambara — Bamanankan
  • Basque — Euskara
  • Belarusian — Беларуская
  • Bengali — বাংলা
  • Bhojpuri — भोजपुरी
  • Bosnian — Bosanski
  • Bulgarian — Български
  • Cantonese — 廣州話
  • Catalan — Català
  • Cebuano — Sinugbuanong Binisayâ
  • Chichewa — Chichewa
  • Chinese (Simplified) — 简体中文
  • Chinese (Traditional) — 繁體中文
  • Corsican — Corsu
  • Croatian — Hrvatski
  • Czech — Čeština
  • Danish — Dansk
  • Dhivehi — ދިވެހި
  • Dogri — डोगरी
  • Dutch — Nederlands
  • English — English
  • Esperanto — Esperanto
  • Estonian — Eesti
  • Ewe — Eʋegbe
  • Filipino — Filipino
  • Finnish — Suomi
  • French — Français
  • Frisian — Frysk
  • Galician — Galego
  • Georgian — ქართული
  • German — Deutsch
  • Greek — Ελληνικά
  • Guarani — Avañe’ẽ
  • Gujarati — ગુજરાતી
  • Haitian Creole — Kreyòl ayisyen
  • Hausa — Hausa
  • Hawaiian — ʻŌlelo Hawaiʻi
  • Hebrew — עברית
  • Hindi — हिन्दी
  • Hmong — Hmoob
  • Hungarian — Magyar
  • Icelandic — Íslenska
  • Igbo — Asụsụ Igbo
  • Ilocano — Ilokano
  • Indonesian — Bahasa Indonesia
  • Irish — Gaeilge
  • Italian — Italiano
  • Japanese — 日本語
  • Javanese — Basa Jawa
  • Kannada — ಕನ್ನಡ
  • Kazakh — Қазақ тілі
  • Khmer — ភាសាខ្មែរ
  • Kinyarwanda — Ikinyarwanda
  • Konkani — कोंकणी
  • Korean — 한국어
  • Krio — Krio
  • Kurdish (Kurmanji) — Kurdî
  • Kurdish (Sorani) — کوردی
  • Kyrgyz — Кыргызча
  • Lao — ລາວ
  • Latin — Latina
  • Latvian — Latviešu
  • Lingala — Lingála
  • Lithuanian — Lietuvių
  • Luganda — Luganda
  • Luxembourgish — Lëtzebuergesch
  • Macedonian — Македонски
  • Maithili — मैथिली
  • Malagasy — Malagasy
  • Malay — Bahasa Melayu
  • Malayalam — മലയാളം
  • Maltese — Malti
  • Maori — Māori
  • Marathi — मराठी
  • Meiteilon (Manipuri) — ꯃꯤꯇꯩ ꯂꯣꯟ
  • Mizo — Mizo ṭawng
  • Mongolian — Монгол хэл
  • Myanmar (Burmese) — မြန်မာစာ
  • Nepali — नेपाली
  • Norwegian — Norsk
  • Odia (Oriya) — ଓଡ଼ିଆ
  • Oromo — Afaan Oromoo
  • Pashto — پښتو
  • Persian — فارسی
  • Polish — Polski
  • Portuguese — Português
  • Punjabi — ਪੰਜਾਬੀ
  • Quechua — Runa Simi
  • Romanian — Română
  • Russian — Русский
  • Samoan — Gagana Samoa
  • Sanskrit — संस्कृतम्
  • Scots Gaelic — Gàidhlig
  • Sepedi — Sepedi
  • Serbian — Српски
  • Sesotho — Sesotho
  • Shona — Shona
  • Sindhi — سنڌي
  • Sinhala — සිංහල
  • Slovak — Slovenčina
  • Slovenian — Slovenščina
  • Somali — Soomaali
  • Spanish — Español
  • Sundanese — Basa Sunda
  • Swahili — Kiswahili
  • Swedish — Svenska
  • Tajik — Тоҷикӣ
  • Tamil — தமிழ்
  • Tatar — Татар теле
  • Telugu — తెలుగు
  • Thai — ไทย
  • Tigrinya — ትግርኛ
  • Tsonga — Xitsonga
  • Turkish — Türkçe
  • Turkmen — Türkmençe
  • Twi — Twi
  • Ukrainian — Українська
  • Urdu — اردو
  • Uyghur — ئۇيغۇرچە
  • Uzbek — Oʻzbekcha
  • Vietnamese — Tiếng Việt
  • Welsh — Cymraeg
  • Xhosa — IsiXhosa
  • Yiddish — ייִדיש
  • Yoruba — Yorùbá
  • Zulu — IsiZulu
  • Breadcrumb

    1. Home
    2. Health and wellbeing
    3. Illnesses and conditions
    4. A to Z

    Colour vision deficiency (colour blindness)

    People with colour vision deficiency find it difficult to identify and distinguish between certain colours. It's sometimes called being "colour blind", although total colour blindness (an inability to see any colour) is very rare.

    About colour vision deficiency

    Colour vision deficiency is usually passed on to a child by their parents (inherited) and is present from birth.

    Although sometimes colour vision deficiency can develop later in life.

    Most people are able to adapt to colour vision deficiency and it's rarely a sign of anything serious.

    Types and symptoms of colour vision deficiency

    Most people with colour vision deficiency have problems distinguishing between shades of red, yellow and green.

    This is known as red green colour vision deficiency. 

    It's a common problem that affects about one in 12 men and one in 200 women.

    Someone with this type of colour vision deficiency may:

    • find it hard to tell the difference between reds, oranges, yellows, browns and greens
    • see these colours as much duller than they would appear to someone with normal vision
    • have trouble distinguishing between shades of purple
    • confuse reds with black

    In rare cases, some people have trouble with blues, greens and yellows instead.

    This is known as blue yellow colour vision deficiency.

    Tests for colour vision deficiency

    Ask for a colour vision test at an opticians if you think you or your child may have a colour vision deficiency, particularly if it started suddenly or is getting worse.

    Colour vision tests don't usually form part of the routine health service test, but you can ask for them.

    Two of the main tests used to diagnose colour vision deficiency are:

    • the Ishihara test, where you're asked to identify numbers within images made up of different coloured dots
    • colour arrangement, where you're asked to arrange coloured objects in order of their different shades

    There are a number of online tests using similar techniques that may help detect a possible problem. But it's best to have a proper test at an opticians if you have any concerns about your colour vision.

    Issues for people with a colour vision deficiency

    Colour vision deficiency isn't usually anything to be concerned about.

    Most people get used to it over time. It won't normally get any worse and it's rarely a sign of anything serious.

    However, it can sometimes cause issues such as:

    • difficulty at school if colours are used to help with learning
    • problems with food, such as identifying whether meat is fully cooked or whether fruit is ripe
    • getting medications confused if they're not clearly labelled
    • trouble identifying safety warnings or signs
    • slightly limited career choices – certain jobs, such as pilots, train drivers, electricians and air traffic controllers, may require accurate colour recognition

    Overall, many people with a colour vision deficiency have few, if any, problems.

    They can do most normal activities, including driving.

    Treating and living with a colour vision deficiency

    There's no cure for inherited colour vision deficiency, although most people are able to adapt to it over time.

    It may help to:

    • tell your child's school if they have problems with their colour vision, so learning materials can be adapted
    • ask your friends or family for help – for example, they can help you choose matching clothes and check whether food is safe to eat
    • install good quality lighting in your home to help you distinguish colours 
    • make use of technology – computers and other electronic devices often have settings you can change to make them easier to use, and there are a number of mobile phone apps available that can help identify colours for you
    • try special tinted lenses – these are worn in one or both eyes to help you distinguish between certain colours, although they only seem to work for some people

    If your colour vision deficiency is caused by an underlying condition or a medication, your symptoms may improve by treating the cause or by using a different medicine.

    Causes of colour vision deficiency

    In the majority of cases, colour vision deficiency is caused by a genetic fault passed on to a child by their parents.

    It occurs because some of the colour sensitive cells in the eyes, called cones, are either missing or don't work properly.

    Occasionally, colour vision deficiency may develop later in life as the result of:

    • an underlying health condition, such as diabetes, glaucoma, age-related macular degeneration and multiple sclerosis 
    • a side effect of a medication including digoxin, ethambutol, chloroquine, hydroxychloroquine, phenytoin and sildenafil
    • exposure to harmful chemicals, such as carbon disulphide and styrene

    Many people also find it more difficult to distinguish between colours as they get older. This is normally just a natural part of the ageing process.

    How colour vision deficiency is inherited

    The genetic fault that usually causes colour vision deficiency is passed on in what's known as an X-linked inheritance pattern.

    It mainly affects boys, but can affect girls in some cases.

    Girls are usually carriers of the genetic fault. This means they can pass it on to their children, but don't have a colour vision deficiency themselves.

    It's usually passed on by a mother to her son. The mother will often be unaffected as she will normally just be a carrier of the genetic fault.

    Fathers with a colour vision deficiency won't have children with the problem unless their partner is a carrier of the genetic fault.

    It can often skip a generation, for example, it may affect a grandfather and their grandson.

    Girls are only affected if their father has a colour vision deficiency and their mother is a carrier of the genetic fault.

    More useful links

    • How to use your health services

    The information on this page has been adapted from original content from the NHS website.

    For further information see terms and conditions.

    Health conditions A to Z

    Or find conditions beginning with A to Z…

    Skip A to Z menu
    • A
    • B
    • C
    • D
    • E
    • F
    • G
    • H
    • I
    • J
    • K
    • L
    • M
    • N
    • O
    • P
    • Q
    • R
    • S
    • T
    • U
    • V
    • W
    • X
    • Y
    • Z

    Help improve this page - send your feedback

    What do you want to do?
    Report a problem
    Which problem did you find on this page? (Tick all that apply)

    Messages

    You will not receive a reply. We will consider your feedback to help improve the site.

    Don't include any personal or financial information, for example National Insurance, credit card numbers, or phone numbers.

    What is your question about?

    What to do next

    Comments or queries about angling can be emailed to anglingcorrespondence@daera-ni.gov.uk 

    If you have a comment or query about benefits, you will need to contact the government department or agency which handles that benefit.  Contacts for common benefits are listed below.

    Carer's Allowance

    Call 0800 587 0912
    Email 
    dcs.incomingpostteamdhc2@nissa.gsi.gov.uk

    Discretionary support / Short-term benefit advance

    Call 0800 587 2750 
    Email 
    customerservice.unit@communities-ni.gov.uk

    Disability Living Allowance

    Call 0800 587 0912 
    Email dcs.incomingpostteamdhc2@nissa.gsi.gov.uk

    Employment and Support Allowance

    Call 0800 587 1377

    Jobseeker’s Allowance

    Contact your local Jobs & Benefits office

    Personal Independence Payment

    Call 0800 587 0932

    If your query is about another benefit, select ‘Other’ from the drop-down menu above.

    Comments or queries about the Blue Badge scheme can be emailed to bluebadges@infrastructure-ni.gov.uk or you can also call 0300 200 7818.

    For queries or advice about careers, contact the Careers Service.

    For queries or advice about Child Maintenance, contact the Child Maintenance Service.

    For queries or advice about claiming compensation due to a road problem, contact DFI Roads claim unit.

    If you can’t find the information you’re looking for in the Coronavirus (COVID-19) section, then for queries about:

    • Restrictions or regulations — contact the Department of Health
    • Travel advice (including self-isolation) — contact the Department of Health
    • Coronavirus (COVID-19) vaccinations — contact the Department of Health or Public Health Agency

    If your query is about another topic, select ‘Other’ from the drop-down menu above.

    For queries about your identity check, email nida@nidirect.gov.uk and for queries about your certificate, email covidcertni@hscni.net.

    For queries or advice about criminal record checks, email ani@accessni.gov.uk

    Application and payment queries can be emailed to ema_ni@slc.co.uk

    For queries or advice about employment rights, contact the Labour Relations Agency.

    For queries or advice about birth, death, marriage and civil partnership certificates and research, contact the General Register Office Northern Ireland (GRONI) by email gro_nisra@finance-ni.gov.uk

    For queries about your GRONI account, email gro_nisra@finance-ni.gov.uk.

    For queries about the High Street Spend Local Scheme,  email HSSS.mail@economy-ni.gov.uk.

    For queries about:

    • Car tax, vehicle registration and SORN
      contact the Driver and Vehicle Licensing Agency (DVLA), Swansea
       
    • Driver licensing and tests, MOT and vehicle testing
      contact the Driver & Vehicle Agency (DVA), Northern Ireland

    If your query is about another topic, select ‘Other’ from the drop-down menu above.

    For queries about your identity check, email nida@nidirect.gov.uk.

     

    For queries or advice about passports, contact HM Passport Office.

    For queries or advice about Penalty Charge Notices (PCNs), including parking tickets and bus lane PCNs, email dcu@infrastructure-ni.gov.uk

    For queries or advice about pensions, contact the Northern Ireland Pension Centre.

    If you wish to report a problem with a road or street you can do so online in this section.

    If you wish to check on a problem or fault you have already reported, contact DfI Roads.

    For queries or advice about historical, social or cultural records relating to Northern Ireland, use the Public Record Office of Northern Ireland (PRONI) enquiry service.

    For queries or advice about rates, email LPSCustomerTeam@lpsni.gov.uk

    For queries or advice about  60+ and Senior Citizen SmartPasses (which can be used to get concessionary travel on public transport), contact Smartpass - Translink.

    If you have a question about a government service or policy, you should contact the relevant government organisation directly.  We don't have access to information about you.

    Related sites

    • gov.uk
    • nibusinessinfo.co.uk

    Links to supporting information

    • Accessibility statement
    • Crown copyright
    • Terms and conditions
    • Privacy
    • Cookies
    • Twitter
    • Facebook
    • YouTube
    • RSS