Dry Eye in Dogs: Causes, Symptoms, Treatments

Tears play an important role in protecting and lubricating the eyes. They clean away debris and keep the eyes healthy. When there is a problem with the quality or quantity of tears, eyes become itchy, red, and painful. Unfortunately, this is what happens in dogs experiencing dry eye. 

Read on to learn more about the causes of dry eye in dogs, symptoms to watch for, and available treatment options. 

What Is Dry Eye in Dogs?

Dry eye is medically referred to as keratoconjunctivitis sicca, and it occurs as a result of poor tear production. Tears are made up of water, fat, and mucus, which are each produced by different glands within the eyes. In most cases of dry eye, the glands that produce the watery part of the tears become damaged, and less tears are produced. In rare cases, glands that produce the fat and mucus portions of the tears are affected, and poor quality tears are made. 

In either case, the tear film does not effectively lubricate the eyes. As a result, the cornea (the front part of the eye that is clear) and the conjunctiva (the red tissue that surrounds the eye) become dry and inflamed. 

Dry eye can occur in dogs of any age, but it is most common in those that are middle-aged and older. This is a very painful condition, and it does have the potential to lead to vision loss if left untreated. 

What Causes Dry Eye in Dogs?

There are many reasons dogs may develop dry eye. Most commonly, a dog’s immune system attacks and damages the glands that are responsible for tear production. It is thought that there may be a genetic component to this process.   

Certain breeds are more prone to developing dry eye due to their anatomy and genetics. Pugs, Cavalier King Charles Spaniels, Cocker Spaniels, Bulldogs, and Boston Terriers are just a few of the breeds that are more likely to develop this condition. 

Less common causes of dry eye include underlying diseases or infections, congenital defects, radiation, and trauma. Giving medications that contain a drug called sulfonamide can also increase the risk of dry eye in some dogs. 

Symptoms of Dry Eye in Dogs

Dry eye can cause significant discomfort. Symptoms of dry eye that affected dogs may experience include: 

• Thick, stringy eye discharge
• Eye redness and inflammation
• Dry or dull corneal appearance
• Blood vessel development on the cornea
• Frequent squinting
• Pawing at or rubbing of the eyes 

If left untreated, dry eye can cause scarring and ulcer formation on the cornea, which may lead to blindness. 

Diagnosing Dry Eye in Dogs

In order to diagnose dry eye, veterinarians most commonly use the Schirmer tear test. During this non-invasive test, a veterinarian will place a small strip of paper between the dog’s eye and lower eyelid for one minute to assess tear production. It is then repeated on the second eye. 

A fluorescent stain can also be used to diagnose keratoconjunctivitis sicca in dogs. During this test, a veterinarian adds one drop of dye to the dog’s eyes and then counts the number of seconds it takes for the tear film to separate. In dogs with dry eye, the tear film breaks apart too quickly.  

As part of a complete eye exam, the veterinarian will also look at all other parts of the eye and check nerves and reflexes. Additional tests, such as checking the eye pressures, may also be done to rule out any other contributing eye problems. 

Dry Eye Treatment for Dogs

Dry eye is treated using medications that are applied directly to the eye in the form of drops, gel, or ointments. Tear stimulants and artificial tears are most commonly prescribed. It is important to know that dry eye will not clear up on its own without some form of treatment.

Tear stimulants, such as Cyclosporine and Tacrolimus, are medications that increase tear production. While these medications work very well in dogs with dry eye, they do take a couple of months to achieve their full effect. Because of this delay, you will not notice an immediate difference in your dog’s eyes. While waiting for a tear stimulant to begin working, your pet’s veterinarian will usually prescribe artificial tears to lubricate the eyes and improve symptoms. Additional medications to treat secondary infections, corneal ulcers, or severe inflammation within the eye may also be prescribed.  

You can expect to apply medications for dry eye at least twice per day. Artificial tears are often applied more frequently. For best results, these medications should only be used as prescribed by your pet’s veterinarian. 

In some instances, surgery may be done if dogs are not responding to topical medications. The goal of the surgery is to use saliva as a new source of tears to lubricate the dog’s eyes. This procedure is complex and performed by a specialist. It does come with risks of anesthesia and of potential complications following the procedure. 

The prognosis for dogs with dry eye is generally good as long as the condition is diagnosed early and there is a good response to treatment. Any underlying conditions that may be contributing to dry eye should also be appropriately managed for best success. However, if a dog does not respond well to treatment, dry eye will continue to progress and can lead to severe eye damage and even blindness. 

Topical treatment and frequent veterinary checkups are needed for the remainder of the pet’s life to manage dry eye. 

Home Remedies for Dry Eye in Dogs

It is not recommended to try any home remedies to treat dry eyes. It is essential for dogs experiencing problematic eye symptoms to be seen by a veterinarian for proper diagnosis and treatment. Because dry eye is most commonly due to immune system dysfunction, specific prescription medications are needed to stimulate tear production and reduce the pain and inflammation present. 

How to Prevent Dry Eye in Dogs

In most cases, dry eye in dogs is unpreventable since it is commonly caused by an overactive immune system. However, avoiding certain medications, decreasing trauma and radiation, and managing underlying conditions that may contribute to dry eye can help prevent this condition in some dogs.