Dog eye infections: causes, symptoms and solutions

Updated 11/12/2023

There’s nothing worse than seeing our precious pooches suffer - and a dog eye infection can be a nasty thing for you both to deal with. 

There are a number of nasty culprits that can cause eye problems in dogs - but they can be difficult to spot. Is it a bacterial infection, viral - an allergy? Here, we’ll run you through the main causes and symptoms to look out for when it comes to dog eye infections - and importantly, when it might be time for Fido to see the vet...

Most common dog eye infections

There are different areas of the eye that can become diseased. Here are the main ones concerning our canine companions:

• Conjunctivitis (also known as pink eye) – inflammation of the soft tissue (conjunctiva) around the eye
• Inflammation of the cornea (surface of the eye)
• Uveitis (an inflammation of the inner eye, such as the iris, ciliary body or choroid)
• Abnormalities of the eyelid or issues affecting the tear glands

Infectious causes

There are two main culprits when it comes to pooch eye infections: bacterial and viral. Sometimes these infections can be localised to just the eye itself and other times they are part of a systemic infection (affecting various areas in the body). The following are all examples of systemic illnesses, many of which can be serious in nature.

Bacterial causes

• Canine brucellosis
• Leptospirosis
• Lyme disease
• Tick-borne diseases such as canine ehrlichiosis

Viral causes

• Canine distemper 
• Herpes
• Hepatitis
• Canine influenza

However, these diseases are not frequently seen, especially if your dog has been vaccinated and is up to speed with their anti-parasite treatment.

More commonly, dogs are often diagnosed with a local bacterial conjunctivitis caused by organisms such as Staphylococcus (mainly S.epidermidis and S.aureus) or Escherichia coli and Pseudomonas species.

In addition to bacteria and viruses, there are a few more things that can harm and irritate our poor pooches’ peepers. Other causes of eye problems in dogs include: fungus, irritants or allergens (such as dirt, hair, fur, dust or debris in the eye), injury (such as a scratch, cut, or ulcer on the eye) and parasites. 

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Symptoms

So, we know what causes these nasty infections in our dog’s eyes. But what are the main dog eye infection symptoms you should be looking out for?

Whether you’re a pet parent yourself or you’re concerned about a pup you’re sitting, here are the tell-tale signs your furry friend might be suffering from a dog eye infection or injury… 

• Swollen or red eye (or eyelids)
• Watery or thick (sometimes smelly) dog eye discharge 
• Squinting
• Tearing
• Blinking excessively 
• Sensitivity to light
• Pawing or rubbing at the eye, or keeping the eye closed
  

If your pooch is suffering from a viral eye infection, they may also act lethargic or have a fever. Check what to do if your dog has a temperature here.

Conjunctivitis in dogs

Bacterial conjunctivitis is a common cause of eye infections in dogs, and - just like with us humans - it can be a nasty thing to deal with.

Conjunctivitis is an inflammation of the mucous membranes (soft tissues) around the eye - in layman's terms, it's when your pup's eyes become red and sore. This is most commonly caused by either an infection or an allergy. However, remember that conjunctivitis can also be caused by a foreign body in the eye, a parasite, eye disease or an injury.

As well as red, swollen eyes, symptoms can include a clear or green discharge. The whites of the eyes may also appear red and irritated, and you might find your pooch is pawing at his eye or blinking more than usual.

Treatment for conjunctivitis can include eye drops, a course of antibiotics or an anti-inflammatory (if the cause is bacterial), or an antihistamine or steroid (if the cause is allergy related).

Conjunctivitis won’t go away on its own. If left untreated, it can spread to the other eye and can sometimes cause permanent damage and even vision loss if not treated quickly. So, if you suspect your pooch has conjunctivitis, it’s important to take them to a vet for an eye exam as soon as possible. 

When it’s not an eye infection

Sometimes, eye problems in dogs can look a lot like an infection - but that’s not always the case.

If it’s not a viral or bacterial infection, or caused by injury or debris, then there's a chance your pooch could have another eye condition. Eye problems such as glaucoma, dry eye (keratoconjunctivitis sicca), tear duct problems, cherry eye, vitamin deficiencies and tumours can have similar symptoms to an eye infection, so can easily be missed. It's also worth noting that some may think a dog has down syndrome, when in reality they've got another serious health issue, such as a brain tumour. So, whatever your concern, be sure to consult your vet.

These conditions can be serious, not to mention cause a lot of pain for our poor pups. So, it’s important for pet owners to seek advice as soon as they suspect their pooch might be suffering.

When you should go to the vet

The short answer: if you suspect your dog might have an eye infection, it's time to see the vet. 

It can be difficult to know whether you're dealing with dog eye allergies vs infection without the help of a pro. So, if you notice any of the symptoms listed (such as swelling, redness or discharge), these are the signs you should get them checked out with your vet. 

Eye infections, such as conjunctivitis, can cause long-lasting damage if not treated quickly - not to mention, it'll cause your poor pooch a lot of pain and discomfort. You also want to make sure that your pet doesn’t have a nasty eye ulcer or scratch on their cornea, which can quickly get worse without treatment.

Once your vet has examined your pup, they'll be able to advise on the cause of the eye concern, and suggest a treatment to get your pooch fighting fit in no time.

Meet our veterinary expert, Rebecca

This article has been checked by veterinarian Rebecca MacMillan BVetMed MRCVS. Rebecca is a companion animal vet who has always had a passion for writing and client communication. Since her graduation from the Royal Veterinary College in 2009 she has gained a wealth of experience in first opinion small animal practice, in both clinical and managerial roles. She currently works in the South West and deals with a variety of routine and emergency appointments, but particularly enjoys medicine cases. Outside of work and writing, she enjoys spending time with her family, including her bouncy flat coated retriever George!

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