A dog close its eye due to eye pain.

Ocular (Eye) Pain and Squinting in Dogs

Overview of Eye Pain and Squinting in Dogs

The most obvious signs of pain associated with eye conditions in dogs are squinting and holding the eyelids closed. Squinting may occur from both external and internal irritation of the eye. Other potential signs of ocular pain include tearing, pawing at the eye, rubbing the face, reluctance to eat hard foods or fully open the mouth, and reluctance to be petted. Eye pain may make the dog very sensitive to light, and the dog may try to avoid bright light. This symptom, called photophobia, is commonly associated with serious eye diseases.

Below, we will give you possible causes of eye pain and squinting in dogs, followed by detailed and in-depth information on how to determine the underlying cause.

It is not always easy to tell if your dog is experiencing eye pain and, sometimes, all you may notice are subtle behavioral changes. It is instinctual for many dogs to withdraw and become more reclusive when they are experiencing eye pain or discomfort. Behavioral changes, such as sleeping more, hiding, decreased appetite, reduced playfulness, and an aggressive disposition are often more subtle demonstrations of eye discomfort. The realization that these subtle expressions are connected to eye disease may only occur after the eye condition has resolved and the pet has resumed there “normal” pattern of behavior.

Causes of Canine Eye Pain

There are many different causes of eye pain. A few are described below:

In contrast to the cornea, conjunctiva and iris, the retina and optic nerve have no pain sensation. Therefore, diseases such as retinal degeneration, retinitis (inflammation of the retina), and optic neuritis (inflammation of the optic nerve) do not cause outward signs of pain.

What to Watch For

Diagnosis of Eye Pain and Squinting

Veterinary care includes diagnostic tests to determine what is causing the eye pain and to direct subsequent treatment. Your veterinarian may do any of the following:

Treatment of Ocular Eye Pain and Squinting in Dogs

Home Care

Recommendations for home care depend upon the underlying cause of the problem. Seeking immediate veterinary medical attention is critical, as many causes of eye pain and squinting are vision threatening and most require specific medical and/or surgical treatment.

Gently clean away excessive eye discharge with a warm, moist cloth to prevent crusting and caking of the hair around the eyes. Cease all attempts if the dog becomes aggressive or if pain seems to worsen with these efforts.

If vision appears to be impaired, minimize stress and risk of injury by confining the pet to a safe area until the cause of the problem is determined. Keep your pet in a dimly lit area or room to help relieve any photophobia.

In-Depth Information on Eye Pain in Dogs

Squinting and photophobia can affect one or both eyes simultaneously. Sometimes, both eyes are squinty even if only one eye is in pain. However, the squinting is usually more dramatic in the diseased eye. It is important to monitor pets closely for subtle behavioral changes, since it is instinctual for many animals to withdraw and become more reclusive when they are experiencing eye pain or discomfort.

Numerous ophthalmic diseases result in eye pain. Diseases involving the eyelids, cornea, conjunctiva, iris, front chamber of the eye, and the orbit result in the most overt signs of eye pain. A thorough ophthalmic and physical examination is necessary to determine which diagnostic tests are needed to determine the cause of the pain.

In younger animals, ocular trauma, inherited or congenital diseases, and infections are common causes of eye pain. In older pets, chronic inflammations, immune-mediated and neoplastic (cancerous) diseases may be more common.

Causes of Eye Pain and Squinting in Dogs

The following are the most important causes of eye pain:


Diagnostic tests used to determine the cause of the eye pain are chosen by your veterinarian based on the findings from the ophthalmic examination, physical examination, prior history of ophthalmic disease, and response to prior treatment. Be sure to inform your veterinarian of all medications currently being administered to your pet.

Other Diagnostic Tests

Your veterinarian may recommend other diagnostic tests on a case-by-case basis, such as:

Treatment of Eye Pain

Do not delay in bringing the pet to a veterinarian for examination as many causes of a painful eye are vision threatening and require immediate medical attention. Many causes of acute (sudden) eye pain are considered medical emergencies and, in certain circumstances, require surgical intervention to preserve vision. For surgical therapy to be the most successful, time is of the essence. If vision cannot be saved, prompt presentation of the pet for medical attention increases the likelihood that the ball or globe may be preserved.

It is important for pet owners of purebred dogs to be familiar with any ophthalmic diseases their breed is predisposed to develop. There are numerous inherited ophthalmic diseases known to afflict certain breeds of dogs and many of these are associated with eye pain and squinting.

Prompt medical and/or surgical therapy is indicated to preserve vision for the following potentially inherited or breed-predisposed ophthalmic diseases:

Breed-Specific Treatment

Brachycephalic (flat-faced) breeds of dogs are predisposed to corneal ulcerations, abrasions, and scratches. These breeds tend to have large, prominent eyes that are more prone to corneal injuries like scratches and ulcers. These breeds also have very shallow orbits or bony eye sockets, and, therefore, more commonly (and easily) displace their eyeball or globe than non-brachycephalic breeds.

Optimal therapy of any acute or chronic ophthalmic disease resulting in symptoms of eye pain depends on determining the correct diagnosis. There are a myriad of potential causes of ocular pain and squinting, and before any treatment can be recommended, it is essential to identify the underlying reason. Nonspecific therapy is not a substitute for definite treatment of the principal disease responsible for the pet’s condition. Initial therapy must be aimed at the primary cause of the eye pain.