About diabetic retinopathy

Diabetic retinopathy is a complication of diabetes, caused by high blood sugar levels damaging the back of the eye (retina). It can cause blindness if left undiagnosed and untreated.

However, it usually takes several years for diabetic retinopathy to reach a stage where it could threaten your sight.

To minimise the risk of this happening, people with diabetes should:

  • ensure they control their blood sugar levels, blood pressure and cholesterol
  • attend diabetic eye screening appointments – annual screening is offered to all people with diabetes aged 12 and over to pick up and treat any problems early on

This page covers:

How diabetes can affect the eyes

Am I at risk of diabetic retinopathy?

Symptoms of diabetic retinopathy

Diabetic eye screening

Reduce your risk of diabetic retinopathy

Treatments for diabetic retinopathy

How diabetes can affect the eyes

The retina is the light-sensitive layer of cells at the back of the eye that converts light into electrical signals. The signals are sent to the brain and the brain turns them into the images you see.

The retina needs a constant supply of blood, which it receives through a network of tiny blood vessels. Over time, a persistently high blood sugar level can damage these blood vessels in three main stages:

  • tiny bulges develop in the blood vessels, which may bleed slightly but don’t usually affect your vision – this is known as background retinopathy
  • more severe and widespread changes affect the blood vessels, including more significant bleeding into the eye – this is known as pre-proliferative retinopathy
  • scar tissue and new blood vessels, which are weak and bleed easily, develop on the retina – this is known as proliferative retinopathy and it can result in some loss of vision

However, if a problem with your eyes is picked up early, lifestyle changes and/or treatment can stop it getting worse.

Read about the stages of diabetic retinopathy

Am I at risk of diabetic retinopathy?

Anyone with type 1 diabetes or type 2 diabetes is potentially at risk of developing diabetic retinopathy.

You're at a greater risk if you:

  • have had diabetes for a long time
  • have a persistently high blood sugar (blood glucose) level
  • have high blood pressure
  • have high cholesterol
  • are pregnant
  • are of Asian or Afro-Caribbean background

By keeping your blood sugar, blood pressure and cholesterol levels under control, you can reduce your chances of developing diabetic retinopathy.

Symptoms of diabetic retinopathy

You won't usually notice diabetic retinopathy in the early stages, as it doesn't tend to have any obvious symptoms until it's more advanced.

However, early signs of the condition can be picked up by taking photographs of the eyes during diabetic eye screening.

Contact your optician immediately if you experience:

  • gradually worsening vision
  • sudden vision loss
  • shapes floating in your field of vision (floaters)
  • blurred or patchy vision
  • eye pain or redness

These symptoms don't necessarily mean you have diabetic retinopathy, but it's important to get them checked out. Don't wait until your next screening appointment.

Diabetic eye screening

Everyone with diabetes who is 12 years old or over is invited for eye screening once a year.

Screening is offered because:

  • diabetic retinopathy doesn't tend to cause any symptoms in the early stages
  • the condition can cause permanent blindness if not diagnosed and treated promptly
  • screening can detect problems in your eyes before they start to affect your vision
  • if problems are caught early, treatment can help prevent or reduce vision loss

The screening test involves examining the back of the eyes and taking photographs. Depending on your result, you may be advised to return for another appointment a year later, attend more regular appointments, or discuss treatment options with a specialist.

Read more about diabetic eye screening

Reduce your risk of diabetic retinopathy

You can reduce your risk of developing diabetic retinopathy, or help prevent it getting worse, by:

  • controlling your blood sugar, blood pressure and cholesterol levels
  • taking your diabetes medication as prescribed
  • attending all your screening appointments
  • getting medical advice quickly if you notice any changes to your vision
  • maintaining a healthy weight, eating a healthy, balanced diet, exercising regularly and stopping smoking

Read more about how to prevent diabetic retinopathy.

Treatments for diabetic retinopathy

Treatment for diabetic retinopathy is only necessary if screening detects significant problems that mean your vision is at risk.

If the condition hasn't reached this stage, the above advice on managing your diabetes is recommended.

The main treatments for more advanced diabetic retinopathy are:

  • laser treatment
  • injections of medication into your eyes
  • an operation to remove blood or scar tissue from your eyes

Read more about the treatment of diabetic retinopathy

Stages of diabetic retinopathy

Diabetic retinopathy develops in stages over time.

If you're diagnosed with diabetic retinopathy after diabetic eye screening, lifestyle changes and/or treatment can reduce the chances of the problem progressing.

The main stages of diabetic retinopathy are described below. You won’t necessarily experience all of these.

Stage one: background retinopathy

This means that tiny bulges (microaneurysms) have appeared in the blood vessels in the back of your eyes (retina), which may leak small amounts of blood. This is very common in people with diabetes.

At this stage:

  • your sight isn't affected, although you're at a higher risk of developing vision problems in the future
  • you don't need treatment, but you'll need to take care to prevent the problem getting worse – read more about preventing diabetic retinopathy
  • the chances of it progressing to the stages below within three years is over 25% if both of your eyes are affected

Stage two: pre-proliferative retinopathy

This means that more severe and widespread changes are seen in the retina, including bleeding into the retina.

At this stage:

  • there's a high risk that your vision could eventually be affected
  • you'll usually be advised to have more frequent screening appointments every three or six months to monitor your eyes

Stage three: proliferative retinopathy

This means that new blood vessels and scar tissue have formed on your retina, which can cause significant bleeding and lead to retinal detachment (where the retina pulls away from the back of the eye).

At this stage:

  • there's a very high risk you could lose your vision
  • treatment will be offered to stabilise your vision as much as possible, although it won't be possible to restore any vision you've lost

Diabetic maculopathy

In some cases, the blood vessels in the part of the eye called the macula (the central area of the retina) can also become leaky or blocked. This is known as diabetic maculopathy.

If this is detected:

  • there's a high risk that your vision could eventually be affected
  • you may be advised to have more frequent specialised testing to monitor your eyes
  • you may be referred to a hospital specialist to discuss treatments that can help stop the problem getting worse

Read more about treating diabetic retinopathy

Treating diabetic retinopathy

Diabetic retinopathy usually only requires specific treatment when it reaches an advanced stage and there's a risk to your vision.

It's typically offered if diabetic eye screening detects stage three (proliferative) retinopathy, or if you have symptoms caused by diabetic maculopathy.

At all stages, managing your diabetes is crucial.

Read about the stages of diabetic retinopathy for more information about what these terms mean.

Managing your diabetes

The most important part of your treatment is to keep your diabetes under control.

In the early stages of diabetic retinopathy, controlling your diabetes can help prevent vision problems developing.

In the more advanced stages, when your vision is affected or at risk, keeping your diabetes under control can help stop the condition getting worse.

Read about what you can do to reduce the risk of diabetic retinopathy progressing

Treatments for advanced diabetic retinopathy

For diabetic retinopathy that is threatening or affecting your sight, the main treatments are:

  • laser treatment – to treat the growth of new blood vessels at the back of the eye (retina) in cases of proliferative diabetic retinopathy, and to stabilise some cases of maculopathy
  • eye injections – to treat severe maculopathy that's threatening your sight
  • eye surgery – to remove blood or scar tissue from the eye if laser treatment isn't possible because retinopathy is too advanced

Laser treatment

Laser treatment is used to treat new blood vessels at the back of the eyes in the advanced stages of diabetic retinopathy. This is done because the new blood vessels tend to be very weak and often cause bleeding into the eye.

Treatment can help stabilise the changes in your eyes caused by your diabetes and stop your vision getting any worse, although it won't usually improve your sight.

Laser treatment:

  • involves shining a laser into your eyes – you'll be given local anaesthetic drops to numb your eyes; eye drops are used to widen your pupils and special contact lenses are used to hold your eyelids open and focus the laser onto your retina
  • normally takes around 20-40 minutes
  • is usually carried out on an outpatient basis, which means you won't need to stay in hospital overnight 
  • may require more than one visit to a laser treatment clinic
  • isn't usually painful, although you may feel a sharp pricking sensation when certain areas of your eye are being treated

Side effects

After treatment, you may have some side effects for a few hours. These can include:

  • blurred vision – you won't be able to drive until this passes, so you'll need to arrange for a friend or relative to drive you home, or take public transport
  • increased sensitivity to light – it might help to wear sunglasses until your eyes have adjusted
  • aching or discomfort – over-the-counter painkillers, such as paracetamol, should help

Possible complications

You should be told about the risks of treatment in advance. Potential complications include:

  • reduced night or peripheral (side) vision – some people may have to stop driving as a result of this
  • bleeding into the eye or objects floating in your vision (floaters)
  • being able to "see" the pattern made by the laser on the back of your eye for a few months
  • a small, but permanent, blind spot close to the centre of your vision

Get medical advice if you notice that your sight gets worse after treatment.

Eye injections

In some cases of diabetic maculopathy, injections of a medicine called anti-VEGF may be given directly into your eyes to prevent new blood vessels forming at the back of the eyes.

The main medicines used are called ranibizumab (Lucentis) and aflibercept (Eylea). These can help stop the problems in your eyes getting worse, and may also lead to an improvement in your vision.

During treatment:

  • the skin around your eyes will be cleaned and covered with a sheet
  • small clips will be used to keep your eyes open
  • you'll be given local anaesthetic drops to numb your eyes
  • a very fine needle is carefully guided into your eyeball and the injection is given

The injections are usually given once a month to begin with. Once your vision starts to stabilise, they'll be stopped or given less frequently.

Injections of steroid medication may sometimes be given instead of anti-VEGF injections, or if the anti-VEGF injections don't help.

Risks and side effects

Possible risks and side effects of anti-VEGF injections include:

  • eye irritation or discomfort
  • bleeding inside the eye
  • floaters or a feeling of having something in your eye
  • watery or dry, itchy eyes

There's also a risk that the injections could cause blood clots to form, which could lead to a heart attack or stroke. This risk is small, but it should be discussed with you before you give your consent to treatment.

The main risk with steroid injections is increased pressure inside the eye.

Eye surgery

Surgery may be carried out to remove some of the vitreous humour from the eye. This is the transparent, jelly-like substance that fills the space behind the lens of the eye.

The operation, known as vitreoretinal surgery, may be needed if:

  • a large amount of blood has collected in your eye
  • there's extensive scar tissue that's likely to cause, or has already caused, retinal detachment

During the procedure, the surgeon will make a small incision in your eye before removing some of the vitreous humour, removing any scar tissue and using a laser to prevent a further deterioration in your vision.

Vitreoretinal surgery is usually carried out under local anaesthetic and sedation. This means you will not experience any pain or have any awareness of the surgery being performed.

After the procedure

You should be able to go home on the same day or the day after your surgery.

For the first few days, you may need to wear a patch over your eye. This is because activities such as reading and watching television can quickly tire your eye to begin with.

You will probably have blurred vision after the operation. This should improve gradually, although it may take several months for your vision to fully return to normal.

Your surgeon will advise you about any activities you should avoid during your recovery.

Risks and side effects

Possible risks of vitreoretinal surgery include:

  • developing a cataract
  • further bleeding into the eye
  • retinal detachment
  • fluid build-up in the cornea (outer layer at the front of the eye)
  • infection in the eye

There's also a small chance that you will need further retinal surgery afterwards. Your surgeon will explain the risks to you.

Preventing diabetic retinopathy

You can reduce your risk of developing diabetic retinopathy, or help stop it getting worse, by keeping your blood sugar levels, blood pressure and cholesterol levels under control.

This can often be done by making healthy lifestyle choices, although some people will also need to take medication.

Healthy lifestyle

Adopting a few lifestyle changes can improve your general health and reduce your risk of developing retinopathy. These include:

You may also be prescribed medication to help control your blood sugar level (such as insulin or metformin), blood pressure (such as ACE inhibitors) and/or cholesterol level (such as statins).

Know your blood sugar, blood pressure and cholesterol levels

It can be easier to keep your blood sugar levels, blood pressure and cholesterol levels under control if you know what level they are and monitor them regularly.

The lower you can keep them, the lower your chances of developing retinopathy are. Your diabetes care team can let you know what your target levels should be.

Blood sugar

If you check your blood sugar level at home, it should be 4 to 10mmol/l. The level can vary throughout the day, so try to check it at different times.

The check done at your GP surgery is a measure of your average blood sugar level over the past few weeks. You should know this number, as it is the most important measure of your diabetes control. 

It’s called HbA1c, and for most people with diabetes it should be around 48 mmol/l or 6.5%.

Read about treating type 1 diabetes and treating type 2 diabetes

Blood pressure

You can ask for a blood pressure test at your GP surgery, or you can buy a blood pressure monitor to use at home. Blood pressure is measured in millimetres of mercury (mmHg) and is given as two figures.

If you have diabetes, you'll normally be advised to aim for a blood pressure reading of no more than 140/80mmHg, or less than 130/80mmHg if you have diabetes complications, such as eye damage.

Read more about preventing high blood pressure and treating high blood pressure


Your cholesterol level can be measured with a simple blood test carried out at your GP surgery. The result is given in millimoles per litre of blood (mmol/l).

If you have diabetes, you'll normally be advised to aim for a total blood cholesterol level of no more than 4 mmol/l.

Read more about preventing high cholesterol and treating high cholesterol

Regular screening

Even if you think your diabetes is well controlled, it's still important to attend your annual diabetic eye screening appointment, as this can detect signs of a problem before you notice anything is wrong.

The earlier that retinopathy is detected, the greater the chance of effectively treating it and stopping it getting worse.

You should also contact your optician immediately if you develop any problems with your eyes or vision, such as:

  • gradually worsening vision
  • sudden vision loss
  • shapes floating in your field of vision (floaters)
  • blurred vision
  • eye pain or redness

These symptoms don't necessarily mean you have diabetic retinopathy, but it's important to get them checked out straight away.

Last updated:
29 March 2022