Finding our dogs with watery, swollen, and red eyes often mean you are dealing with dog eye allergies. They can be seasonal or chronic, depending on the cause, and they are every bit as aggravating to your dog as they are to us.
Of course, daily eye care, like using a dog eye cleaning wipe to clean up tear stains and boogers, should be a normal part of preventing eye issues. But allergies in the eye, called allergic conjunctivitis (doggy pink eye), can be tricky to treat.
Plus, we need to be able to discern an allergic reaction from infection to have a better idea of how to treat the problem safely. So we consulted a medical overview of Canine Conjunctivitis and Blepharitis to break it down.
What causes canine eye allergies?
According to the ACDV task force, the most common cause of eye allergies in dogs is environmental. This means fleas, pollen, dust, mites, or mold spores. The most common food allergies are chicken, eggs, dairy, beef, wheat, and soy.
The dog’s eyelid and conjunctiva (the protective layer over the eye) always face contact with airborne particles. The word “atopy” refers to a genetic predisposition for cells in charge of the immune system, like mast cells, to overreact to potential allergens.
So dogs who tend to get atopic dermatitis (itchy, inflamed skin) are also more prone to allergic conjunctivitis.
When foreign particles like pollen activate mast cells, they release compounds like histamine and tryptase in the dog’s tears. This causes watery eyes. Fibroblast cells (that sometimes cause dog skin tags) release cytokines, which causes inflammation, so the eyes become red and swollen.
Allergies can be acute or chronic.
It’s vital to tell your vet if your dog also has itchy skin because dogs with itchy skin are more likely to develop allergic conjunctivitis. This is more common in dog breeds like West Highland White Terriers, German Shepherds, Bull Dogs, and Retrievers.
Dog eye allergies: symptoms
Dog allergy symptoms in the eye include:
- Watery eyes (in our article on dog eye boogers, we discuss other kinds of eye discharge that you may also see).
- Swelling (sometimes until the eye is swollen shut)
- Squinting or winking
- Pawing or scratching at their face
- Rubbing their face against objects (see our article on dogs rubbing their face on carpets for other reasons they may be doing this.)
- Signs of distress like whining or rapid panting.
If the allergic reaction is severe, perhaps after a dog is stung by a bee, be on the lookout for breathing problems or anaphylaxis and take your dog to the vet immediately. An extremely swollen face or throat can restrict breathing, so keep their airways open.
Eye allergies vs. dog eye infections
Allergies do not always cause conjunctivitis, so many dog eye infections can look like an eye allergy. However, infections from bacteria typically have thicker discharge that could be green, yellow, or pus-like. Eye infections can also be from serious viruses like Parvo.
An allergy can cause an infection, especially if your dog is scratching or rubbing the eye. Any trauma to the skin from excessive rubbing can create a secondary eye condition.
Dogs with genetic eye issues that leave them with dry eye, cherry eye, or eyelid deformities are also more prone to issues that may look like allergies. However, to complicate matters further, many of the breeds prone to eye problems, like the French Bull Dog, is also extremely prone to allergies.
Sadly, this means one needs to take all eye symptoms seriously and have a vet check out anything strange or out of the ordinary. This way, your vet can rule out eye conditions like corneal ulcers or infections.
Dog eye allergy treatment
A vet needs to check on any allergic reaction in the eyes to ensure there is not another condition, such as a scratch on the cornea. They should then give your dog corticosteroids like hydrocortisone to help the inflammation and itching.
Remember, they must check for a scratch first because steroidal eye drops can interfere with healing. They may then prescribe oral antihistamines or other medication.
Can you use human medication for dog eye allergies?
Speak to your vet before you use any human medicine for your dog. Some vets will make suggestions, but they need to weigh in on what’s safe.
A common human eye drop, Visine constricts blood vessels and can cause permanent damage to a dog’s eyes. Many other types of eyedrops for allergies are also dangerous to dogs.
You can read more about which eye drops are safe and which are not in our article on human eye drops for dogs.
People often give dogs Benedryl for allergies, which can help with hives and swelling. But human antihistamines aren’t very effective for dogs. One of the most effective human antihistamines is Cetirizine, and in a study, only 18% of dogs with skin allergies responded to it.
Human antihistamines can also contain decongestants and other compounds that may be toxic to canines.
Dog eye allergies home remedies
You can do several things at home to help your dog with eye allergies and relieve discomfort. The best thing is to always go to the vet for medication and dog-specific eye ointments, and make sure your vet checks for other issues like corneal ulcers.
But to help treat your dog at home, you can:
1. Apply a cold compress to the eye
Apply a soft, cold compress to your dog’s eyes to relieve the itching and inflammation. Don’t use anything frozen solid. Rather, put a few wet dishcloths in the freezer until they are cold to the touch, and then hold them gently against the eye.
2. Wash your dog’s eyes out with a saline eyewash
Ordinary human saline washes are usually fine for dogs but always speak to your vet before using any human medication. You can wash your dog’s eyes out up to twice a day. You can also use artificial tears to keep their eyes lubricated.
3. Put a cone over your dog to prevent scratching
A dog that scratches or rubs their eyes can cause more damage. Ask your vet for a cone to keep them away from the eye area until the issue has passed. Your vet should also give medication for the itch.
4. Identify the allergen for dog eye allergies
The most important thing you can do is to identify the allergen as soon as possible. If your dog’s eyes swell, itch, and become red after they get a certain medication or roll in the grass, it can be easier to figure out the cause. Seasonal allergies are also a good indication that it may be pollen.
Keep the air clean in the home with air purifiers and a dehumidifier can help dry out dust mites.
But with chronic allergies, it can be harder. An elimination trial and ELISA tests will help you identify what your dog is allergic to if it is a food allergy. The most common dog food allergies are extremely widely used pet food staples like chicken, beef, lamb, wheat, and soy.
More often than not, the problem is either contact with an allergen like lawn fertilizer or something in the environment. The most allergic reactions are to dust mites, pollen, flea, and other insect bites like bees.
Eye allergies are extremely uncomfortable for our pets, and our own eyes can water in sympathy when we see it. It’s tough to deal with environmental allergens like pollen, so it’s important to work with your vet to ensure you have medication ready for Spring if your dog is prone to seasonal allergies.
You can use saline washes and cold compresses to relieve some symptoms at home. Keep your dog from rubbing or scratching their eyes to prevent injury or infection. But dogs need to see the vet to get the proper medication and check for other possible causes.
Tamsin De La HarpeAuthor
Tamsin de la Harpe has nearly two decades of experience with dogs in rescue, training, and behavior modification with fearful and aggressive dogs. She has worked closely with veterinarians and various kennels, building up extensive medical knowledge and an understanding of canine health and physiology. She also spent two years in the animal sciences as a canine nutrition researcher, focusing on longevity and holistic healthcare for our four-legged companions.
Tamsin currently keeps a busy homestead with an assortment of rescue dogs and three Bullmastiffs.