Blindness in dogs

Blindness in dogs can be due to old age, eye diseases (e.g. cataracts) or due to other diseases (e.g. diabetes) and may be gradual or sudden. Read our guide to help find out what can cause severe visual problems in dogs and how to know if your dog is going blind.

What are the signs of blindness?

Blindness and severe visual problems can affect a dog’s behaviour, causing them to bump into furniture, appear less confident, be easily startled or they may be reluctant to jump off the sofa. Some conditions may also change the way that the eye looks, making it bloodshot, watery or cloudy.

How a dog is affected depends on what’s causing their blindness. Common signs of vision loss might include:

• Bumping into furniture, walls or people
• Seeming clumsy
• Being anxious or hesitant, especially in new places or around unfamiliar dogs
• Regularly seeming anxious, confused or easily startled
• Barking at things more often
• Not wanting to use stairs or jump on or off furniture
• Unable to find things, such as toys
• Not wanting to go for walks or go outside, especially as it’s getting dark
• Seeming slower or more hesitant on walks
• Being more clingy than usual
• Having less eye contact with you
• Drinking or sleeping more than usual
• Their eyes are cloudy, red, puffy or swollen. Sometimes their pupils appear large or don’t change size in different levels of light
• Having irritated or painful eyes, e.g. squinting, pawing at their face or not wanting you to touch their head

What are the types of blindness?

There are several types of blindness in dogs. Some come on quickly (sudden onset) while others develop slowly (gradual onset). Some dogs are completely blind, others are partially blind and some types of blindness may be intermittent.  

• Gradual loss of sight – Dogs are very good at adapting, so slow progressive blindness may be difficult for owners to spot. Dogs that are affected by gradual blindness often initially struggle in poor light
• Sudden loss of sight – Suddenly becoming blind may be frightening for a dog, so they may be anxious, hesitant or may bump into things. Noticing a sudden change in your dog’s behaviour makes it easier to spot this type of blindness. A sudden change in vision can be more difficult for dogs to cope with, so they may need extra support and care
• Partial blindness – Affected dogs may keep some degree of vision. This could be because only one of their eyes is affected, or their vision in both eyes is reduced (e.g. it’s blurry or they can still detect shapes or changes in light)
• Intermittent blindness – This type of blindness comes and goes and is often caused by trauma or poor blood flow to the eye
• Night blindness – Some conditions affect a dog’s ability to see in the dark, and so some may struggle more at night or in a dark room
• Complete blindness – This is a complete lack of vision. Affected dogs are unable to see anything at all and are unable to detect shapes, colours or changes in light

When should I contact my vet?

Speak to your vet if you’re concerned your dog has problems seeing or if their eye looks different. For some types of blindness, receiving early treatment can make a big difference, so never put off contacting your vet. Blindness can sometimes be a sign of an underlying health issue, so it’s best to get your dog checked out.

What can cause blindness?

Blindness in dogs can be caused by an injury, ageing or health conditions, such as PRA (progressive retinal atrophy), cataracts, glaucoma or diabetes. Some health conditions directly affect the eye (e.g. PRA and cataracts), while others, such as diabetes, heart disease or liver problems, have a knock-on effect on the eye.

Some eye conditions are genetic, others are caused by a dog’s lifestyle and some may be a combination of the two. Some dogs may be born with an eye condition (known as congenital), while others may develop them as they grow older.

What can cause sudden blindness in dogs?

Sudden blindness can be caused by an injury, SARDS (sudden acquired retinal degeneration syndrome), retinal detachment or damage to the optic nerve. A sudden loss of sight can be quite scary for your dog, so they may need extra help and patience to adapt. If you think your dog has suddenly gone blind, speak to your vet.

How to prevent blindness in dogs?

You can reduce a dog’s risk of some types of blindness by feeding them a healthy diet, giving them plenty of exercise and taking them for regular check-ups. Doing these things can help to reduce their risk of high blood pressure, diabetes, obesity and cancer, which can all lead to blindness.

However, there are other types of blindness that can‘t be prevented or predicted, such as inherited eye conditions, injuries or trauma.

What age do dogs go blind?

Dogs can go blind at any age. Sometimes, dogs may develop blindness when they’re young, but it’s more common in older dogs. Not all dogs have visual problems, but for those that do, the age their vision deteriorates will depend on what’s causing it, their overall health, their breed etc. As your dog gets older, it’s important to take them for regular check-ups and eye screening.

Why is my dog only blind in one eye?

Just like humans, dogs can go blind in one or both eyes. Blindness in one eye could be caused by many issues, including injuries, cataracts or tumours. Dogs are good at adapting, so some owners may find it difficult to spot when only one eye is working. 

Can seizures cause blindness?

Having fits may cause some dogs to have some after-effects, such as being confused, being unable to stand or having problems seeing. Being unable to see after fitting is quite common and can last up to two hours. Always speak to your vet if your dog is fitting for an unknown reason, or if you’re concerned about any after-effects of a seizure.

Find out more about epilepsy in dogs.

What diseases can cause blindness in dogs?

The main causes of blindness and visual problems in dogs include cataracts, uveitis, diabetes, glaucoma and PRA (progressive retinal atrophy). Other causes include SARDS (sudden acquired retinal degeneration syndrome), autoimmune conditions, tumours and breed-specific health issues.

Cataracts

A cataract is a cloudy patch that appears on the lens of the eye. This patch can grow, blocking out light as it becomes bigger and making it difficult to see. A cataract can spread across the whole lens and can cause total blindness. Dogs with cataracts typically have cloudy-looking eyes. Some owners may notice that their dog finds it difficult to see, especially when it’s darker. A dog can be affected in one or both eyes and can develop cataracts at any age, although it’s much more common in older dogs. Cataracts in younger dogs tend to be inherited or may be a result of diabetes or an injury.

Diabetes

Visual problems in diabetic dogs are very common. One study found that around 80 per cent of diabetic dogs developed cataracts within less than a year and a half of being diagnosed. It’s thought that frequent high levels of sugar in the bloodstream can affect the eye, making cataracts more likely. As well as cataracts, diabetes is also associated with glaucoma and other visual problems. 

Find out more about diabetes.

Uveitis

Uveitis is the swelling or inflammation of the middle part of the eye. It can be caused by an infection, injury, autoimmune disease or cancer. Dogs with uveitis usually have red, painful eyes. They may squint, keep their eye shut or try to avoid bright light. Their eyes may be watery or there may be a discharge or blood.

Glaucoma

Glaucoma is caused by a build-up of pressure in the eye, causing pain and problems seeing. If caught early, glaucoma can initially be managed, so it’s important you speak to your vet as soon as you notice any signs. Glaucoma often develops gradually and causes pain (squinting, pawing at the eye or not wanting you to touch their head), bloodshot eyes, dilated pupils, or cloudy/blue-tinged eyes. The risk of glaucoma can be influenced by a dog’s genes, age, their breed, injuries and other diseases. 

PRA

PRA (progressive retinal atrophy) is a group of painless conditions that cause the parts of the eye that are sensitive to light to break down. PRA produces a gradual loss of vision in both eyes, eventually leading to total blindness. A number of breeds are affected by PRA, and although the clinical effects are usually the same, each breed’s version of PRA is often caused by a different genetic mutation. Some versions of PRA may appear in young dogs (early-onset) or others may appear in adult dogs (late-onset). Sadly, there is no cure for PRA.

SARDS

Sudden acquired retinal degeneration syndrome (SARDS) is a rare eye condition that causes parts of the eye to break down, leading to permanent blindness. This syndrome has no known cause but comes on quickly and progresses to complete blindness within a few days or weeks. Research has found that affected dogs tend to be smaller and middle-aged. SARDS has been reported in many different breeds and crossbreeds, but is more common, although still rare, in Dachshunds, Pugs, Miniature Schnauzers, Maltese, Cocker Spaniels and a number of other breeds. Because the effects are so sudden, dogs don’t have time to adapt and may find it difficult to adjust to a complete loss of sight. Affected dogs may seem disorientated, scared/stressed, may be off their food or may bump into things. Unfortunately, there is no treatment available for SARDS.

Dry eye

Dry eye, also known as keratoconjunctivitis sicca, or KCS, occurs when a dog is unable to produce tears, making their eyes very sore. Dry eye is often a chronic condition that requires long-term use of medicated eye drops. Affected dogs may rub at their eyes, squint or be sensitive to light. Their eyes may be inflamed and reddened, or the cornea may appear dry and dull. There is commonly a thick, mucousy discharge in or around the eye. If this condition is not treated early or is not managed effectively, it can lead to visual problems and blindness.

Retinal detachment

The retina is a thin, light-sensitive layer of tissue at the back of the eye. If this tissue comes loose, it can cause a complete or partial loss of vision. A dog’s retina can become detached for many reasons, including high blood pressure, autoimmune conditions, injuries and infections. Symptoms of a detached retina may vary, depending on how severe the detachment is and what’s caused it.

Corneal ulcers

A corneal ulcer is a sore on the transparent covering of the eye. These sores can be incredibly painful and may look like a mark, scratch or small crater on the eye or may not even be visible. Dogs with a corneal ulcer may keep rubbing at their eye, may keep it shut or their eye may be red, inflamed, cloudy or weeping. Corneal ulcers can be caused by injuries, dry eye, infections or entropion (a condition in which the eyelid turns into the eye and the eyelashes rub against the eyeball). Any dog can get corneal ulcerations, but dogs with prominent eyes, such as flat-faced dogs (e.g. Pugs, Shih Tzus and Cavalier King Charles Spaniels) may be more likely to suffer from them. If left untreated, corneal ulcerations may lead to infections and blindness.

Autoimmune conditions

Autoimmune diseases occur when the body attacks itself, thinking that its own cells are invaders. Some rare autoimmune diseases, such as pannus and Uveodermatologic syndrome can affect the eye and cause blindness.

Tumours

There are many ways that a tumour can cause blindness, as the way in which animals see is complex. Tumours may be found in, on or around the eye or they may appear on the optic nerve or in the brain.

High blood pressure

High blood pressure can damage delicate structures in the eye, causing visual problems that lead to blindness. High blood pressure in dogs is often linked to diabetes, thyroid problems, obesity, hormone issues and kidney disease. If your dog suffers from any of these conditions, it’s worth taking them for regular check-ups at the vet.

Breed specific conditions

Some dogs may have genetic conditions that can cause visual impairment or lead to total blindness. These are often specific to their breed or a small number of other breeds, such as collie eye anomaly (CEA), certain types of progressive retinal atrophy (PRA), Stargardt disease, neuronal ceroid lipofuscinosis (NCL5, NCL8 and NCL12) or fucosidosis (Fuco).