Glaucoma is an eye condition that causes loss of vision, or reduced vision, if it is not detected and treated early enough. It usually happens when pressure builds up inside the eye, damaging the optic nerve. Visit an opticians or your GP if you have any concerns about your vision.

Symptoms of glaucoma 

Glaucoma affects your vision when the optic nerve, which connects your eye to your brain, becomes damaged. It usually occurs when the fluid in the eye cannot drain properly. This increases the pressure inside the eye and puts pressure on the optic nerve.

Glaucoma doesn't usually cause symptoms to begin with. It is often only picked up during a routine eye test.

Many people don't realise they have it. This is because it develops slowly over many years and tends to cause a loss of peripheral vision (the edge of your vision) at first.

Both eyes are usually affected, although it may be worse in one eye. Without treatment, it can eventually lead to blindness.

Very occasionally, glaucoma can develop suddenly and cause:

  • intense eye pain
  • a red eye
  • a headache
  • tenderness around the eyes
  • seeing rings around lights
  • blurred vision

When to get medical advice 

Visit an opticians or your GP if you have any concerns about your vision.

If you have glaucoma, early diagnosis and treatment can help stop your vision getting worse.

If you develop symptoms of glaucoma suddenly (see above), go to your nearest eye casualty unit or emergency department as soon as possible.

This is a medical emergency that may require immediate treatment.

Types of glaucoma 

There are several different types of glaucoma.

Some of the main types include:

  • primary open angle glaucoma – the most common type, which tends to develop slowly over many years
  • primary angle closure glaucoma – an uncommon type that can develop slowly or quickly
  • secondary glaucoma – glaucoma caused by an underlying eye condition, such as uveitis (inflammation of the eye)
  • normal tension glaucoma – where the pressure inside the eye is at a normal level
  • childhood glaucoma (congenital glaucoma) – a rare type that occurs in very young children, caused by an abnormality of the eye

Causes of glaucoma 

Glaucoma is usually caused by a blockage in the part of the eye that allows fluid to drain from it. This can lead to a build-up of fluid and pressure in the eye and can damage the optic nerve.

It's often unclear exactly what causes it. There are some things that can increase your risk, including:

  • your age – it can affect people of all ages but is most common in adults in their 70s and 80s (glaucoma becomes more likely as you get older)
  • your ethnicity – people of African, Caribbean or Asian origin are at a higher risk of glaucoma
  • your family history – you're more likely to develop glaucoma if you have a parent or sibling with the condition

It's not clear whether you can do anything to prevent glaucoma. But having regular eye tests will help make sure it's picked up as early as possible, and that you can stop your vision getting worse.

Tests for glaucoma 

Glaucoma can usually be detected during a routine eye test at an opticians. This is often before it causes any noticeable symptoms.

Several quick and painless tests can be carried out to check for glaucoma.

You should have a routine eye test at least every two years. 

If tests suggest you have glaucoma, you should be referred to an ophthalmologist (eye doctor) to discuss treatment.


Treatments for glaucoma 

It's not possible to reverse any loss of vision that occurred before glaucoma was diagnosed. But treatment can help stop your vision getting any worse.

The treatment recommended for you will depend on the type of glaucoma you have. Your GP or hospital consultant will discuss your treatment options with you.

You'll also probably need regular appointments. This is to monitor your condition and make sure treatment is working.

Outlook for glaucoma 

The outlook for glaucoma largely depends on the type of glaucoma you have, but generally:

  • it often results in some degree of permanent vision loss, although most people retain useful vision for life
  • it may affect your ability to do certain tasks, such as driving
  • only a small number of people will end up totally blind

The outlook is better the earlier glaucoma is diagnosed and treated.

This is why it's so important to get your eyes tested regularly and to make sure you follow your recommended treatment plan.

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

For further information see terms and conditions.

This page was published December 2017

This page is due for review December 2019

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