Lifting the Lid on Pet Eye Health: common eye conditions of dogs and cats

written by Dr Jo de Klerk - Sep 16, 2019

Eye diseases are one of the most common reasons why dogs and cats present to their veterinarian. The eyes are two vital organs that allow your pet to explore and take in their surroundings. They capture wavelengths of light, and convert them to neural impulses to the brain when they hit the retina at the back of the inner eyeball. The outer aspect of the eye, known as the cornea, is one of the most sensitive tissues of the body, as it is densely packed with sensory nerves. This means that eye conditions can cause considerable discomfort.

Eye diseases can present in a variety of ways. Eyes can appear inflamed and red, swollen or with discharge, and the discharge can be watery, green, yellow or brown in color. There may be some sensitivity to light, known as blepharospasm, and the animal may be reluctant to open their eyes. In cats, in particular, the third eyelid may protrude from the inner corner of their eye. If there has been a chronic problem, edema might begin to appear, which is characterized by a blue hue to the surface of the eye. This is different to a cloudiness or blue hue in the lens of the eye, which we will talk about later.

If you notice any of these symptoms in your pet’s eyes, it is important to see a veterinarian immediately. Eyes can both improve and deteriorate rapidly, and so ocular conditions should be treated as urgent.

Common Eye Conditions of Dogs and Cats

Corneal Ulcers

Corneal ulcers are inflammatory abrasions on the outer aspect of the eye. They can range in severity, although even the most minor ulcers will still be very painful. The cornea is made up of several layers, and the deeper the ulcer, the more serious it is. It is a delicate part of the eye, and therefore an ulcer can form easily from dust, hair, scratches (especially in fighting cats), dry eyes and anatomical issues.

When a veterinarian examines an eye, which may have an ulcer, they will first check that there is not a foreign body present. This is most likely to happen to dogs who jump through areas of long grass, and get grass seeds lodged under an eyelid. If there is something still in the eye, the veterinarian will remove it after numbing the eye with local anesthetic. Next, the veterinarian will place several drops of fluorescein stain in the eye, which only attaches to the deeper layers of the cornea. Under a blue light, this stain will highlight how much of the cornea is damaged.

Treatment depends on the severity of the ulcer, but it is likely your veterinarian will prescribe some form of drops to repair the defect and prevent it from becoming infected. We carry Fucithalmic Viscous Eye Drops at Canadian Pharmacy World. The active ingredient is 1%/5gm Fusidic Acid and it is produced by Methafarm. Prices start at $22.50 per unit.


Conjunctivitis is a common condition, both in dogs and cats, but especially cats. Conjunctivitis is an inflammation of the conjunctiva, which is the lining on the inside of the eyelids. As a result, it is commonly referred to as ‘Pink Eye’. It is usually infectious in nature, and commonly affects the eyes bilaterally. Conjunctivitis is characterized by reddening of the conjunctiva, blepharospasm (squinting) and a green or yellow discharge from the eyes. In cats, the third eyelid may also protrude.

Cats which live in multi-cat households can contract viruses or bacteria which lead to a disease complex called ‘Cat Flu’ or ‘Snuffles’. As part of this disease complex, a cat suffering from ‘Cat Flu’ will almost always have conjunctivitis. Dogs, on the other hand, tend to contract conjunctivitis from putting their head into dirty, dusty areas, or socializing with other dogs who have infected eyes.

If your pet has conjunctivitis, your vet will prescribe antibiotic drops to treat it. Like corneal ulcers, Fucithalmic is also a common first-line treatment, which you can purchase from Canadian Pharmacy World with a valid prescription from your veterinarian. You should ensure that after applying it to the eye, you thoroughly wash your hands, as some causes of conjunctivitis are transmissible to humans.

Photo Credit: conjunctivitis treatment for cats, by Dr. Joanna De Klerk
Photo Credit: conjunctivitis treatment for cats, by Dr. Joanna De Klerk

Keratoconjunctivitis Sicca is also known as Dry Eye or KCS. However, it is much more than simply having dry eyes, and can have serious complications if left untreated. Dry Eye is most common in our canine friends, and it is rarely seen in cats. It manifests when the eyes do not produce enough tears. As a result, the cornea becomes itchy and uncomfortable, and the eyes produce a mucus discharge. It can also predispose to ulceration, which in turn brings more discomfort to the eyes.

Tear production can be compromised due to two reasons. The first reason is an auto-immune reaction to the tear glands. This is when the body destroys the tear-producing part of the eye. The second reason is an injury to the nerve which innervates the tear gland, meaning that it doesn’t receive the nervous stimulation from the brain to tell it to make tears. Luckily, there are drops available to help down-regulate the immune system’s attack on the tear glands, which is the more common cause of Dry Eye. Unfortunately, if Dry Eye is a result of nerve injury, then surgery to remove the eye, or transpose a salivary duct to the eye to provide lubrication from saliva, are the only treatment options.

At Canadian Pharmacy World, we sell Restasis Ophthalmic Emulsion. The active ingredient is 0.05% Cyclosporine, and it is available in eye drops or a single-use vial. The brand Restasis is manufactured by Allergan in Canada and India, prices start from $71.67 for 30 vials. The generic Cyclosporine is also known as Cyclomune eye drops manufactured by Sun Pharma in India, and prices start from $28.33 for 3 ml. Dr Rachel Matusow explained in an article how cyclosporine has been shown to increase production of tears, decrease blood vessel formation and pigmentation in the cornea, and increase the production of mucin, thereby improving comfort in dogs with Dry Eye.


In the middle of the eye is the lens. The lens should be a clear structure, which refracts the light hitting the eye onto the retina at the back of the eyeball. When the lens becomes opaque, this is known as a cataract. Cataracts result in poor vision, because they prevent light from reaching the retina, where it can be sent to the brain for processing into an image.

Cataracts can be easily confused with nuclear sclerosis, which is natural aging of the lens. Both make the eye look cloudy, with a white or blue hue; however, light can pass through nuclear sclerosis to the back of the eye. A veterinarian can differentiate between the two by examining the eye with an ophthalmoscope.

Cataracts can be the result of a genetic predisposition, as well as underlying diseases, such as diabetes. However, they can also be due to bad luck. They are more common in dogs than cats, although they are seen in both species. A study by Lim et. al. showed that the only medical option for treating cataracts is with topical anti-inflammatories, however this is not a long-term solution, and the cataract will still develop albeit slowly. The most superior treatment option is lens replacement surgery, which can be carried out by a veterinary ophthalmologist.

Photo Credit: cataracts treatment for dogs, by Joanna De Klerk
Photo Credit: cataracts treatment for dogs, by Joanna De Klerk


All eyes should maintain their internal pressure without a problem, however, if the animal is suffering from high blood pressure or an ocular disease which places pressure on the eye, such as a tumor behind the eye, the internal eye pressure can become imbalanced. This can lead to pain, dilated pupils, inflammation, excessive tears and bulging eyes. This syndrome, resulting from the increased pressure, is called glaucoma.

There are several treatment options for glaucoma, including topical drops and surgery to remove the eye. The underlying cause should first be established and addressed. Eye drops can also be used to decrease the intraocular pressure through lowering inflammation, lowering internal fluid production and promoting fluid drainage.

At Canadian Pharmacy World, we stock two treatment options for glaucoma, which your veterinarian may prescribe for your pet. Research conducted by Gelatt and MacKay showed that topical drops are just as effective as treating glaucoma as oral medications. Azopt drops contain 1%/5ml Brinzolamide. They are manufactured by Alcon and prices start from $28.33 per unit. We also stock Cosopt Ophthalmic drops, which come in 60 x 0.2ml Preservative Free Dose and 10 ml bottle, it is manufactured by Merck and prices start from $101 for 60 x 0.2ml, or $91.67 for a 10ml bottle. The generic Dorzolamide/Timolol is available in a dose of 2%/0.5%. It comes from India also known as Dorzox-T manufactured by Cipla, and prices start from $30 for a 5ml bottle.

How to Administer Eye Drops

When it comes to eyes, veterinary medicines and human medicines are often the same. Very few eye drops are licensed specifically for animals, and therefore human eye drops are used. This means that if your vet has provided you with a prescription, you can purchase eye drops for your dog from Canadian Pharmacy World.

Once your pet’s eye drops have arrived, you should commence treatment as soon as your vet has directed. Be certain to read the instructions on the label thoroughly, as not all eye drops are administered in the same way. Some drops require one application per day, others will be as frequent as every few hours. Likewise, some drops will require refrigeration, or to remain in the box out of sunlight, whereas others are much more stable during the handling process.

When you wish to administer the drops, firstly ensure the eye is clean from discharge. If it is not, cleanse the area with sterile eyewash or cooled, boiled water. Next, clean your hands thoroughly, and if possible, enlist the help of another person to restrain your pet. If you do not have extra help, it is easiest to bring your pet’s hindquarters to your body, so that if they back up, you are in the way. This provides an excellent position for you to lift your pet’s chin, and gently open the eyelids with your index finger and thumb. This will allow the eyes to open wide and point to the ceiling when receiving the drops. When you bring the bottle to the eye, rest your hand on your pet’s head, so that if he moves, your hand moves with him rather than pokes him in the eye. Squeeze the bottle to administer the prescribed number of drops into the eye, and let your pet relax and blink. This will move the drops around the eye evenly.

If you do not see an improvement after 24-48 hours of administering the drops, or if the eye continues to deteriorate, you should consider revisiting your veterinarian for a reassessment.

How to Order Medication from Canadian Pharmacy World

If your pet needs eye drops, for which your veterinarian has provided a prescription, you can order them from Canadian Pharmacy World. We are a certified and trusted online pharmacy, which provides high quality medications at competitive and affordable prices.

Ordering your pet’s medications is as easy as four simple steps:

1. When you have searched for and found the medication, click on ‘add to cart’.

2. When your product is in the shopping cart, you can sign-up as a new customer or login as an existing customer.

3. Click on ‘submit order’ to confirm your order.

4. You can then upload your prescription or send it via fax, mail or email.

Afterwards, a customer service agent will call you to review your order.

Here is a link to a video outlining these steps:

How to Order

We are a certified member of the Canadian International Pharmacy Association (CIPA) so you can be sure that shopping with Canadian Pharmacy World is safe, secure and convenient.


Dr Jo de Klerk graduated from the Royal Veterinary College and works as a veterinarian and writer. She has a Master's in Tropical Animal Health. Her clinical interests are pain management, rehabilitation, and community practice.


Leave your comment:

Your email address will not be published. Required fields are marked with *.

Enter Code:
not case-sensitive

While the above article is based on thorough research, we do not claim to offer a substitute for medical advice from a qualified healthcare provider. The article was written for information and educational purposes only. We aim to provide helpful information to our readers, but cannot provide a treatment, diagnosis, or consultation of any sort, and we are in no way indicating that any particular drug is safe or appropriate for you and your individual needs. To receive professional medical attention, you must see a doctor.