We all remember that iconic moment from the 1980s film, Say Anything, when John Cusack stands outside his ex-girlfriend’s window with a comically oversized tape player. He holds it aloft and the strains of Peter Gabriel’s “In Your Eyes” echo through the scene and our collective cultural memory. Did you know that when dogs get pink eye, in many cases, it’s because something has gotten in their eyes?

Pink eye, or conjunctivitis in dogs, is an ocular health condition in which the conjunctiva becomes inflamed. What’s conjunctiva, then? Conjunctiva is a kind of lining that covers the white part of the eyeball, as well as the inside of the eyelid and the nictitating membrane, also known as the third eyelid. Conjunctiva keeps eyes lubricated and protects them, for the most part, against the elements and foreign objects.

In general, you’ll recognize the symptoms of conjunctivitis in dogs when the whites of their eyes become pink or red. The eyelids can become swollen, and the eyes may present a discharge that can range from clear and watery to greenish with pus. Dogs that blink excessively or rub at their eyes with their paws might have pink eye. There are three distinct varieties of conjunctivitis in dogs, as well as a fourth that affects newborn puppies right around the time their eyes are opening on the world for the first time. We’re going to give you a brief overview of each kind of conjunctivitis in dogs, what causes them, and how to minimize the risk of pink eye.

Follicular conjunctivitis in dogs

The first is follicular conjunctivitis. Follicular conjunctivitis in dogs occurs when a foreign object or irritant gets under a dog’s eyelid. A group of cells forms around it, creating what’s known as a follicle. That follicle’s rough surface irritates the conjunctiva, leading the eye to become pink or red, and the eyelid to become swollen. The dog’s eyes may produce more tears than normal, and the dog may paw at her face, signalling irritation.

In many cases, a saline eye wash or eye drops will help the foreign object to dislodge itself and the follicle to go away. If symptoms persist, a trip to the veterinarian may be required. The follicle may remain, and the rough surface formed continues to irritate the eyelid, the nictitating membrane, and the eye itself.

Serous conjunctivitis

Serous conjunctivitis, or dry eye, is the most common kind of pink eye in dogs. It occurs when the dog’s tear ducts don’t provide enough lubrication for the eye, leading it to become dry and increasingly irritated. Causes of this sort of conjunctivitis in dogs include relentlessly cold or dry weather, dust, smoke, allergens, or other irritants. The dryness makes the eyes pink and inflamed, with a clear, watery discharge. This kind of conjunctivitis in dogs can be usually be resolved with saline eye wash or eye drops.

Purulent conjunctivitis in dogs

Evidence that you should always be mindful of your dog’s overall health, purulent conjunctivitis in dogs occurs when serous conjunctivitis, or dry eye, goes untreated. In especially poor sanitary conditions, a dog with serous conjunctivitis can be exposed to bacteria like staph or strep. That’s when pink eye in dogs turns nasty. As far as complications of conjunctivitis in dogs go, it’s just about the worst when bacteria finds its way into a dog’s eyes. Clear and watery discharge associated with pink eye turns into mucus and pus. Crust from this discharge begins to build around the dog’s eyes. Left untreated long enough, purulent conjunctivitis in dogs can lead to blindness. Bad news all the way around.

Neonatal conjunctivitis

The fourth and final form of conjunctivitis in dogs is also bacterial in nature, and affects newborn puppies. As we know, the eyes of baby puppies don’t open for the first couple of weeks of life. If the whelping box, or their immediate surroundings for those first couple of weeks, aren’t carefully tended to and cleaned regularly, the presence of bacteria can cause neonatal conjunctivitis. Pink eye in baby puppies whose eyes are not yet fully open is as awful as it sounds. Conjunctivitis in puppies causes their eyes to bulge and their eyelids to swell. The goo that forms can prevent puppy eyes from opening at all and blindness to result. Newborn puppies with these symptoms should be treated by a veterinarian immediately.

Can conjunctivitis in dogs be prevented?

Prevention of conjunctivitis in dogs is tricky, because we don’t have much of a say in the operation of our own tear ducts, much less those of our dogs. Nor do we have any real control over allergens or occasional irritants that can cause the mild and common occurrence of serous conjunctivitis in dogs. Regular and consistent hygiene, on the other hand, we can and should concern ourselves with.

Regular baths for our dogs, along with making sure their living environments, from floors to couches to dog beds, are clean and tidy, can take care of many potential irritants and smaller foreign objects that can disturb a dog’s eye health. Limit a dog’s exposure to smoke, whether from candles, incense, tobacco, or other sources.

Since dogs can’t tell us when they are ill at ease, it’s vital that we pay attention to things that they might not. Look into your dog’s eyes daily. It only takes a moment, and the earlier you can catch the symptoms of conjunctivitis in dogs, the quicker you can get them addressed. Have you encountered cases of conjunctivitis with your dogs? Which variety did you deal with? How did the situation resolve? Share your experiences with pink eye in the comments!

Learn more about dogs with Dogster:

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• Four Things You Should Know About Your Dog’s Growl