If a dog's eye is swollen, it is usually due to inflammation or allergies. In individual cases it can also indicate a rolled eyelid, a prolapsed nictitating gland, glaucoma, a corneal ulcer or even a tumor.
If the swelling is only under the eye, then it is usually a sign of an injury. In some cases it can also occur due to insect bites. [1]
Below you will learn about the 10 most common causes, how the corresponding points manifest themselves and what you should do in a specific case.
Are you worried or unsure? Then click here to start a live chat with a veterinarian.
#1 Inflamed eyelids
If a dog's eyelid becomes inflamed, doctors speak of “blepharitis”. The most common causes of this include:
- Allergies
- Tumor disease
- Congenital anomalies
- Mushrooms
- Tumors
- Other infections
- Bacterial infestation [2]
It can usually be recognized by the fact that not the entire eye, but only the eyelids, are swollen. Other typical symptoms of this are:
- Severe itching
- One eye appears only half open
- Watery discharge from the eye
- Eye begins to fester
- Frequent scratching of the face
- Redness of the eyelid
- Loss of pigment [3]
According to statistics, this primarily affects brachycephalic breeds. This refers to dogs with a short muzzle and a flat face.
For diagnosis, a small tissue sample is usually taken to be examined in the laboratory. Treatment then depends on the specific cause. [4]
If a dog's eyelids become inflamed, the entire eye usually swells slightly. Typically, it can be recognized by the eye watering slightly, the eyelids being red, and the dog constantly rubbing its face due to the itching.
#2 Allergies
According to studies, between 10 and 20% of all dogs struggle with allergies. Here, contact with a potential allergen triggers an immune reaction.
Theoretically, anything can be an “allergen.” In practice, however, the following allergens are usually behind the allergic reaction:
- pollen and grasses
- Parasites like fleas
- Cat hair and dander
- food ingredients
- Smoke from cigarettes [5]
Pollen in particular is known to cause swelling and redness when it comes into contact with the eyes. Other classic signs are here:
- Watery eyes
- Dog rubs face
- Constant shaking of the head
- Dog snorts and sneezes
- Red skin around the eyes
- Sudden breathing problems
- Runny nose [6]
Since there is no cure for allergies, prevention with an allergy test is the best option. Medication can also help with acute problems.
When dogs suffer from allergies, this is usually noticeable through red and swollen eyes. In most cases, affected four-legged friends also sneeze frequently, shake their heads constantly and have a runny nose.
#3 Injuries
Dogs always explore their environment head first. In combination with their natural curiosity, injuries to the face and eyes are much more common.
The hunting instinct is also to blame, because in hunting mode they can easily run through a thorn bush. Typical triggers for injuries are:
- Scratches by cats
- Insect bites
- Driving while dog looks out the window
- Contact with sharp blades of grass
- Fight with another dog
- eyesore [7]
To suppress the pain, dogs often try to keep their eyes closed or blink unusually often. Other signs of this include:
- Redness in the eye
- Constant flow of tears
- Swollen eye
- Sudden loss of vision
- Visible red veins in the eye
- Rubbing the face [8]
In any case, you should consult the vet as a precaution. In simple cases, eye drops can be enough. In severe cases, surgery may also be necessary.
Injuries to the eye usually result in the eye becoming red and swollen. It is also typical for there to be a constant watery discharge from the eye or for the dog to even completely close one eye. Cats are often responsible for this.
This website is for sale.
#4 Inflammation of the vascular membrane
The vascular membrane consists of 3 parts and is located inside the eye. If one or all of these parts become inflamed, doctors speak of “uveitis”.
It is an inflammation of the inner eye that can take three different forms. The most common causes of this include:
- Diabetes
- High blood pressure
- Poisonings
- Tumor disease
- Autoimmune diseases
- Injuries to the eye
- Viral infections [9]
One of the first signs is severe redness in the white area of the eye. Swelling and excessive tearing can also indicate this. Other symptoms include:
- Eye becomes cloudy
- Severe pain
- Dog avoids bright light
- Small pupil
- Accumulation of blood
- Dog keeps eye closed
- Frequent blinking [10]
Diagnosis is primarily about identifying the affected areas. Because that is essential for the treatment. Medication and eye drops are usually sufficient here.
If parts of the vascular skin become inflamed in dogs, this can usually be seen from a distance due to severe redness and cloudy eyes. It is also typical that the entire eye swells, the dog blinks very often and avoids bright light.
#5 Glaucoma
Glaucoma refers to a group of different diseases of the optic nerves. Depending on the expression, 5 different forms are distinguished. Typical triggers are:
- Congenital anomaly
- Inflammation of the eye
- eye tumor
- Impaired fluid drainage
- Displacement of the lens [11]
Veterinarians often refer to this as “glaucoma”. The most common initial symptoms include constant tearing and redness of the eyes. Other signs include:
- Cloudy eye
- swelling of the eye
- Loss of appetite
- Decreasing eyesight
- Lack of motivation
- Eyeball protrudes
- Watery eye [12]
For diagnosis, the degree of visual impairment is usually determined in order to be able to assess the stage. The vet also usually measures the internal pressure of the eyes.
Early action is the key here. If left untreated, it can lead to permanent blindness. Medication and eye drops are usually used for treatment. [13]
Dogs with glaucoma usually develop increasingly cloudy eyes that are constantly watery. In addition, the eyes are usually swollen so that the eyeballs protrude. If left untreated, vision deteriorates so much due to the disease that dogs go blind.
#6 Corneal ulcer
The cornea of the eye consists of 3 layers. You can compare it to a car windshield because of its protective function.
An ulcer usually occurs as a result of injuries to one or even all three layers. But illnesses can also be behind it. Typical triggers here are:
- Deeper scratches
- Cushing's syndrome
- Aggressive soap
- Diabetes
- Hypothyroidism
- Contact with chemicals [14]
In most cases, the eye is swollen and a cloudy spot can be seen because there is a buildup of fluid. Other signs of this include:
- Frequent blinking
- Red eyes
- Dog has mucus in his eye
- Constant scratching of the eyes
- Decreasing vision
- Dog keeps eye closed [15]
A corneal ulcer is extremely painful. If you suspect this, you should consult the vet immediately. The therapy then depends on the cause.
If an ulcer forms in the cornea of the eye, it is usually accompanied by visible symptoms such as frequent blinking. The dog's affected eye is usually very red, swollen and becomes increasingly cloudy if left untreated.
#7 Conjunctivitis
Inflammation of the conjunctiva is one of the most common eye infections. Veterinarians also refer to this as “conjunctivitis”. The most common triggers include:
- Congenital defects
- Blockage of the tear ducts
- Allergic reactions
- Eyes too dry
- Glaucoma
- Viral infections [16]
Conjunctivitis is also colloquially known as “red eye” because the eyes become very red and sometimes even swollen.
Due to the inflammation, it is also not uncommon to see large amounts of yellow-greenish mucus around the eye. Other signs of this include:
- Pus on the eye
- Eyelids stick together
- Dog rubs face
- Excessive blinking
- swelling of the eyelids
- Dog only opens his eyes half way [17]
Anti-inflammatory drops and medications are usually used for treatment. To avoid permanent damage, you should seek help early on.
Dogs with conjunctivitis usually have very red eyes, which are also accompanied by itching. Typically, the eye also swells and a yellowish mucus forms, which primarily accumulates on the inner edge of the eye.
#8 Rolled eyelid
If the upper or lower eyelid is turned inwards, doctors also speak of “entropion”. In practice, this causes the eyelashes to constantly rub against the eye.
In many cases it is also the trigger for subsequent infections or even eye ulcers. The following breeds are said to be most commonly affected:
- English bulldog
- German boxer
- Shar Pei
- Great Dane
- bullmastiff
- Chow Chow [18]
This condition is immediately recognizable to a trained eye. It also occurs more often at the bottom than at the top. The most common signs include:
- Constant flow of tears
- Red and swollen eyes
- Frequent blinking
- Sudden corneal ulcer
- Inflammation of the eyes
- Mucous discharge [19]
The only effective treatment here is surgical correction. This is usually carried out between the ages of 6 and 12 months and has a very high chance of success.
Dogs with a rolled eyelid usually struggle with chronic eye problems. Rubbing your eyelashes against your eyes can cause redness, swelling and infections. Here, surgery is the only form of therapy.
#9 Prolapse of the nictitating gland
A prolapsed nictitating gland is also known colloquially as “cherry eye” because a large red bubble forms on the inside of the eye.
This is the detached “nictitating membrane gland”, which is responsible for the production of tears. The following breeds are most commonly affected here:
- Pekingese
- beagle
- Bernese Mountain Dog
- rottweiler
- Boston terriers
- English bulldog
- Maltese [20]
The exact cause…