Dry eye in dogs: Causes, associated risks and treatment

Canine keratoconjunctivitis sicca (KCS), also known as “dry eye” in dogs, is a common condition that is caused by a lack of tear production in the lacrimal (tear) gland and/or the gland of the dog’s third eyelid.

Tears are vital for properly lubricating the eyes and removing harmful debris that may enter them. If tear production is inadequate due to KCS, it can cause both short and long-term problems for a dog’s vision.

Causes of dry eye in dogs

KCS can be caused by a number of underlying conditions that interfere with a dog’s ability to produce tears. Of these conditions, the most common are immune-mediated conditions that interfere with tear gland production.

Examples of immune-mediated diseases in dogs are:

• Immune mediated hemolytic anemia

• Immune mediated thrombocytopenia

• Immune mediated polyarthritis.

Other causes of KCS include:

• Small or missing tear glands

• Canine distemper virus

• Nerve loss in or around the eyes and other nervous system effects (this is called neurogenic KCS)

• Hypothyroidism

• Cherry eye – a condition that involves a prolapsed (“popped-out”) third eyelid gland

• Side effects of certain medications, including sulfonamides and other sulfa drugs

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Symptoms

There are a variety of signs that may indicate KCS is present in your pup. If research pictures of dry eye in dogs, it’s easy to note the irritation associated with the condition.

Primary symptoms of dry eye in dogs can include:

• Irritation

• Redness

• Pain

• Dullness

• Thick, green or yellow discharge

• Excessive blinking or squinting

• Keeping the eyes closed

• Secondary conditions like corneal ulcers and bacterial conjunctivitis

• Corneal hyperpigmentation or scarring, which appears as a dark film over the eyes 

Both eyes are often affected at the same time by KCS, meaning that these symptoms will likely occur in both eyes. It is possible for one eye to experience worse symptoms; regardless, it’s important to take symptoms seriously and contact a veterinarian for an exam. 

Risk factors

Certain breeds of dog are more susceptible to dry eye syndrome than others, including:

• English Springer Spaniel

• Pug

• Boston Terrier

• English Bulldog

• Cocker Spaniel

• Lhasa Apso

• Shih Tzu

• Yorkshire Terrier

• Pekingese

• Miniature Schnauzer

• Bloodhound

• Cavalier King Charles Spaniel

• West Highland White Terrier

• Samoyed

Age can also contribute to the likelihood of your dog developing KCS. Experts have noted that KCS affects middle-aged and older dogs most often.

If your dog is one of these breeds, especially if they are older, be sure to note any changes in their eyes and report them to your vet as soon as possible.

Diagnosis

In order to diagnose KCS, a veterinarian will perform several tests to evaluate tear production. 

One test in particular is the Schirmer tear test (STT), which is performed by measuring the amount of tear film your dog produces in a minute’s time. This is collected on special paper strips.

Your vet may also use a biomicroscope, a special instrument that aids in examining the surface cells of the cornea, as well as the tear film, to check for abnormalities. 

It’s important to check for other serious eye conditions that may affect the tear production in your dog to provide the most accurate diagnosis. To do so, your vet may perform corneal staining to identify any corneal ulcers or an intraocular pressure (IOP) test to identify any signs of canine glaucoma. 

Dry eye treatment for dogs

The ultimate goal for treating dry eye in dogs is to stimulate and restore tear production to protect the cornea. If your dog has an underlying condition, such as an eye infection or glaucoma, that condition will also be treated.

KCS requires proper care on a constant basis, from the time it is diagnosed through the rest of the dog’s life. Dry eye treatment for dogs often involves medication, but severe cases may require surgical correction.

Dry eye drops for dogs

Eye drops are used to stimulate tear production and can also help moisten the eyes. Many vets recommend administering medicated eye drops for dogs such as tacrolimus or cyclosporine twice a day, depending on the condition. 

Neurogenic KCS is often treated with a medication called pilocarpine, which is also available in a drop form.

Your vet will guide you on which of these are the best drops for your dog’s dry eye.

Tear film replacement

In many cases, a tear film replacement is recommended in combination with the eye drops used to stimulate tear production. 

There are a variety of solutions, ointments and gels that are designed to replace tear film — but they must be applied multiple times a day, and should always be used as a supplement to eye drops, as they are not an effective treatment on their own.

Surgery for KCS

If medication does not provide adequate results, surgery may be required to treat KCS. The procedure for this is known as parotid duct transposition. A salivary duct located in the mouth is repositioned to allow the salivary secretions to reach the surface of the eye. 

These salivary secretions share similar properties to tears, but parotid duct transpositions are usually only performed under very severe circumstances.

Dog dry eye home remedy

If your dog suffers from dry eyes due to seasonal allergies or other mild causes, your vet may recommend giving them artificial tears to soothe and moisten the area. Keeping the eyes clean is also crucial.

Please note that mild cases of dry eye are different from KCS, so it’s important to differentiate between the two under a vet’s supervision before beginning treatment at home. Your dog may require more intense care for their condition, and it’s not worth risking your dog’s eye health.

How to apply eye drops for your dog

Eye drops for dogs with dry eye should be applied as directed by your veterinarian, especially when they are prescribed for conditions as serious as KCS.

It can be tricky to apply eye drops for your dog, but the following guidelines can help ensure they get all the medicine they need safely and effectively.

1. Always wash your hands both before and after administering eye drops and other medications.

2. Gently clean the area around the eyes with a warm, wet washcloth.

3. Cradle your dog’s head — it may be helpful to have a trusted assistant help with this.

4. Hold the medicine bottle using your dominant index finger and thumb, then pull down the lower eyelid with your opposite thumb. If needed, use your other fingers on your non-dominant hand for more support around your dog’s jaw.

5. Place the bottle close to the eye, but be careful not to touch it. Aim for the center of the eye as you squeeze the prescribed amount of medicine onto it.

6. Your dog’s natural response will be to blink several times, which will help to spread the medicine around the surface of the eye.

Be sure to use praise before, during and after you give the medicine and offer a treat when the process is complete. This will make things easier on both you and your furry friend.

Outlook for dry eye syndrome in dogs

Further complications can arise if KCS is not treated, from discomfort for your dog to corneal scarring and permanent vision damage. Some cases may not respond to treatment if they are not diagnosed early enough in the span of the condition, so it is very important to have regular checkups with your vet to encourage your dog’s well-being and any recovery that is needed.

Furthermore, be sure to follow treatment exactly as prescribed to improve your dog’s condition and avoid serious problems. Providing your pet with the proper care is always the best way to keep them happy and healthy.

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Page published on Wednesday, September 15, 2021