Optic neuritis

This page contains a summary of our information on optic neuritis. To read our full information, download our factsheet:

Reduced vision

Optic neuritis usually causes reduced vision or loss of vision. Vision becomes blurred, dim, or faded. It usually comes on over the course of a few days and may continue to worsen over the first two weeks. Optic neuritis usually affects vision in one eye, but in some types, it may affect both eyes.

Optic neuritis commonly affects the central area of your vision, but can also affect peripheral (side) vision. You use your central vision for detailed tasks such as looking at a smartphone, reading, watching television, or seeing people's faces.

Depth perception

Reduced vision in one eye can cause difficulties with depth perception. This can cause problems with judging distances. It may make going up and down stairs or kerbs, crossing roads, pouring liquid into a cup, or ball sports more difficult. You may need to take more time when doing these things.

Flashing or flickering lights

Some people with optic neuritis describe seeing flashing or flickering lights.

Reduced colour and contrast

Colours, particularly reds, can appear “washed out” or less bright than usual. It may be more difficult to pick out objects against their backgrounds, particularly if they are a similar shade or colour. For example reading yellow text on a yellow background. This is known as having reduced contrast sensitivity.

Heat related vision changes

Vision may temporarily worsen due to heat. For example during a holiday in a hot country, after a bath, during exercise, when feeling stressed, or after having hot food and drinks. This usually improves once you cool down, for example, sitting down in a cool area.

Pain or discomfort

In the first few days, it’s common to experience discomfort or pain around your eyes. This typically worsens with large eye movements. This pain is not usually so great that it stops you sleeping at night. If the pain is worse than this, it would be important to let your GP or eye specialist know as there may be another cause. The pain may be present before the change in your vision, or it may happen at the same time. It will normally only last a few days.

The most common type of optic neuritis is “demyelinating” optic neuritis. In most people, the cause of demyelinating optic neuritis is not known. This is called “idiopathic”, meaning that no cause for the inflammation can be found.

Some cases may be “autoimmune”, where the immune system mistakenly attacks healthy tissue, causing inflammation. Certain autoimmune conditions can be associated with optic neuritis including:

• multiple sclerosis (MS)
• neuromyelitis optica spectrum disease (NMOSD)
• myelin oligodendrocyte glycoprotein autoantibody disease (MOGAD)
• chronic relapsing inflammatory optic neuritis (CRION)

Less commonly, optic neuritis can be caused by:

• infection - infectious optic neuritis
• a reaction to how your body's immune system copes with an infection or vaccination – post-infectious optic neuritis and post-vaccination optic neuritis.

The most common type of optic neuritis is demyelinating optic neuritis. Demyelination is where the protective myelin coating on your nerve fibres breaks down. When your myelin breaks down patches of demyelination, known as lesions, occur. These can slow down or stop the signal being carried by the nerve to your brain. This can then affect your vision.

The reasons why demyelination happens are not clearly understood. Evidence suggests that the body’s own immune system causes the myelin to break down (autoimmune).

Optic neuritis and multiple sclerosis (MS)

There is a link between demyelinating optic neuritis and MS.

MS is a condition where the myelin is damaged and can affect any part of the central nervous system (CNS), which includes the brain and spinal cord. The CNS controls many body functions such as balance, movement, emotions, and vision. MS can cause a large range of symptoms depending on which part of the CNS has been affected, and these can vary widely from person to person.

If you are diagnosed with demyelinating optic neuritis, your ophthalmologist (eye doctor) may explain that this could be linked to MS. Research shows that about 38 in 100 people who have an episode of demyelinating optic neuritis go on to develop MS within 10 years. However, many people with optic neuritis (about 62 in 100) do not develop MS.

If you are worried about MS, talk to your ophthalmologist or your GP. Only a specialist in the brain, spinal cord and nerves (known as a neurologist) can diagnose MS. To confirm a diagnosis of MS, you would need to be referred for further tests.

Optic neuritis usually gets better on its own without treatment. For many people, vision typically gets worse over several days to two weeks, then slowly begins to improve. Pain improves before vision.

A large study in 1992 called the Optic Neuritis Treatment Trial (ONTT) looked at the best way to treat optic neuritis in about 400 people. It found that, even without treatment, more than 9 out of 10 people’s vision improved within the first month from when vision loss began.

Treatment is beneficial in some cases, for example, in optic neuritis linked to NMOSD, MOGAD and CRION, or if you have certain antibodies. Early steroid treatment (ideally within 48 hours of optic neuritis starting) in these cases can improve recovery and vision outcome.

Your doctor will decide on treatment options depending on the type of optic neuritis and how much it is affecting your vision.

Pain relief

If optic neuritis causes pain or discomfort, your GP or ophthalmologist can advise you about pain relief. Often, over-the-counter pain medications are enough to help, but occasionally steroids are needed. This pain or discomfort will normally only last for a few days.

Steroids

If needed, treatment for the most common demyelinating type of optic neuritis is high dose steroids. These can be given:

• Through a vein (intravenously) – usually in hospital for 3 to 5 days.
• As tablets (oral steroids) – usually for 3 days. This is sometimes given instead of intravenous treatment because it’s simpler and easier to manage.
• Sometimes you need to have steroids for a longer time. In this case, the dose of the tablets is slowly reduced over time (called a taper). The taper can last from one week up to six months. It is very rarer to need steroids longer than this.

Steroid treatment can help vision recover faster and may protect the optic nerve. But studies show they do not change how well your vision recovers in the long term. This is because the brain is very good at adapting and compensating for changes to the eye. Therefore, the small benefit from this treatment would need to be weighed against the risks and side effects of taking high dose steroids. Most people with optic neuritis will not have steroid treatment.

Steroids are more likely to be used if:

• You have a rarer type of optic neuritis, such as MOGAD, CRION or NMOSD, where steroids can improve recovery.
• Your vision is very poor in the other eye.
• Symptoms are especially severe or distressing.
• Your vision loss affects important daily tasks, such as driving for work.

Immunosuppressants

Some rare types of optic neuritis, such as MOGAD, CRION and NMOSD may need treatment with medication to calm down (supress) the immune system. In some cases, this treatment is long term to help prevent optic neuritis happening again. Your ophthalmologist or neurologist will explain if this type of treatment is needed, based on the type of optic neuritis you have.

Treating Infection

If your optic neuritis is caused by infection, you may need treatment with antimicrobial or antifungal medication. Steroids can be harmful in infectious optic neuritis.

Vision starts to improve as inflammation goes down and your optic nerve begins to recover. Recovery may be quick at first, then slow down. Vision can keep improving for 6 – 12 months. By about a year, your vision will usually have recovered as much as it is going to.

It may be difficult to predict what your vision will be like in the long term. For many people, if this is the first time they’ve had optic neuritis, vision makes a good recovery, even if it was badly affected to start. Most people with the most common type of optic neuritis, acute demyelinating optic neuritis, will make an excellent long term visual recovery.

Sometimes, tests like an eye exam or OCT scan show lasting damage to the optic nerve, called optic atrophy. This can lead to long lasting changes in vision, such as:

• Colours looking faded
• Difficulty seeing contrast
• Less sharp vision
• Trouble judging depth or movement

Even if optic atrophy is seen on an exam, some people notice no symptoms at all in their everyday vision.

In rare cases, recovery is limited, and vision remains reduced even after the inflammation has gone. This is more likely if optic neuritis is linked to another underlying condition.

If you’ve had optic neuritis once, there’s a chance it could happen again in either eye.

For the common type (demyelinating optic neuritis), the ONTT study found that:

• About28 in 100 people had another episode within five years.
• About 35 in 100 people had another episode within 10 years.
• this also means most people (about 65 in 100 people) did not have a second episode in 10 years.

With rarer types, such as NMOSD, CRION or MOGAD related optic neuritis, the chances of having another episode are higher.

It’s not always possible to predict if optic neuritis will return. Your ophthalmologist can give you more guidance based on your medical history and whether this is your first episode of optic neuritis.

Most people with optic neuritis make a good recovery of their vision and do not have any long-term problems with their sight. A few people may be left with some long term changes to their sight. If so, much can be done to help you make the most of your remaining vision and adapt to any changes.

Monocular vision (reduced vision in one eye)

Optic neuritis usually affects just one eye. While you’re waiting for your vision to improve, living with reduced sight in one eye (monocular vision) can feel challenging in the beginning. This usually become easier as you adjust, and the difficulties should go away once your vision improves.

Making the most of your sight

If both your eyes are affected, or if the affected eye was your only good eye, then making changes or using aids to make the most of your remaining sight can help. This may mean making things bigger, using brighter lighting, or using colour and contrast to make things easier to see. Ask your ophthalmologist, optometrist or GP about having a low vision assessment. During this assessment, a low vision practitioner can explore visual aids or techniques that can help you. .

You can also find out tips for making the most of your sight by downloading our booklet: