How do I know if my dog has an eye infection?

Disclaimer: This article, its content and related references, does not constitute veterinary advice and should not be considered a substitute for veterinary care.

Eye infections in dogs are common and are treated differently depending on the cause. Dog owners should be aware of common eye infection symptoms, such as eye discharge, red eyes, and inflammation around the eyes, and understand the importance of getting veterinary help as soon as possible. Read on to learn:

• What an eye infection is
• Common symptoms of canine eye infections
• How dogs get eye infections
• How veterinarians diagnose and treat eye infections in dogs

Bacteria and viruses are responsible for most canine eye infections. Eye infections may occur in a healthy eye or following an injury, such as a scratch or a foreign body in the eye. They may occur as an isolated infection or as part of a systemic disease, like an upper respiratory tract infection. Treatment often involves medicated eye drops and addressing any underlying health conditions that have contributed to the development of the infection.

Canine eye infections are common. They develop when an infectious agent enters the eye and replicates, leading to inflammation and associated symptoms. They can be described based on the tissue that’s infected as well as by the specific disease-causing agent. Bacteria, viruses, fungi, and parasites can cause eye infections in dogs. The different parts of the eye that can become infected and inflamed include:

• Eyelid (blepharitis)
• Conjunctiva (conjunctivitis)
• Cornea (keratitis)
• Structures within the eyeball (uveitis)

The suffix “-itis” refers to inflammation. The eye can become inflamed without the presence of an infection, so it’s important to avoid the assumption that an inflamed eye is always an infected eye.

Bacterial and viral conjunctivitis are the most common types of eye infections in dogs. The conjunctiva is a thin, clear membrane covering the eyeball and the inside of the eyelids that helps protect the eye and keep it moistened. Bacterial and viral infections affecting the eye can be in the eye directly or result from a systemic disease that affects other parts of the body, such as an upper respiratory tract infection.

When a part of the eye becomes infected, inflammation occurs as part of the immune response to fight it. Inflammation can lead to symptoms such as:

• Swollen or red tissue lining the eyes
• Eye discharge or excessive tearing
• Red or bloodshot eyes
• Pawing at the eyes
• Squinting
• Blinking excessively
• Holding the eye closed
• Cloudy eyes
• Light sensitivity

Eye infections can come on suddenly or appear gradually, and can be very uncomfortable or painful for dogs. Symptoms vary between individuals and range in severity.

Inflammation of the eye may occur in association with a systemic health issue that affects the entire body, so additional symptoms may be present, such as:

• Coughing or sneezing
• Nasal discharge
• Itchiness
• Hair loss
• Excessive thirst and urination
• Vomiting or diarrhea
• Lethargy
• Loss of appetite

It’s important to note any additional symptoms a dog has, even if they seem minor. Knowing that a dog is showing other signs of illness at home, even minor symptoms, can help a veterinarian make an accurate diagnosis.

Viral, parasitic, fungal, and bacterial infections can all affect a dog’s eyes. These conditions include:

• Bordetella (kennel cough)
• Leptospirosis
• Lyme disease
• Canine infectious hepatitis (adenovirus)
• Distemper virus
• Fungal infection (blastomycosis)
• Parasitic infection

Conditions that interfere with the eye’s ability to fight off infections can make the environment within the eye favorable for infection. This includes conditions that change the eye itself, such as:

• Eye injuries, including foreign material in the eye
• Eyelid and eyelash disorders
• Dry eye (keratoconjunctivitis sicca)
• Corneal ulcers
• Cherry eye
• Coloboma
• Ocular tumors and cancer
• Brachycephalic ocular syndrome

Various eye conditions can have similar symptoms to eye infections, even if there’s no infection present. However, changes in the eye can increase the likelihood of injury or infection.

Foreign matter and irritants can irritate the eye and interfere with its normal defense mechanisms. These can include:

• Dust, pollen, and other airborne irritants
• Allergic inflammation
• Heavy UV exposure

Autoimmune diseases and medications that compromise your dog’s immune system can also increase the likelihood for developing eye infections.

Is my dog at risk for eye infections?

Dogs with noninfectious eye disease, autoimmune disorders, or who take immunosuppressant drugs are at higher risk of developing eye infections. In addition, brachycephalic breeds — breeds with flat faces and shorter facial bones and muzzles — are more at risk for eye conditions and eye injuries due to the shape of their face and their round, bulging eyes. Some individuals can’t close their eyelids completely, leading to dry eyes and an increased risk of conjunctivitis and eye injury. Because of these anatomical issues, brachycephalic breeds often need long-term daily therapy, such as artificial tears and other medication.

Breeds such as French bulldogs, pugs, and boxers are becoming more popular. It’s important for dog owners to understand that owning a brachycephalic breed means the dog is more likely to have health issues, including eye conditions and brachycephalic airway syndrome.

A vet uses a physical examination, an eye exam, and diagnostic testing to determine underlying cause in a dog who presents with signs of an eye infection. In addition to determining if an infection is present, this also helps identify the type of infection and what part of the eye is affected. An eye examination may include:

• Examining the eye with a light and magnifying lens in a darkened room
• Fluorescein stain to see corneal ulcers and scratches
• Schirmer tear test to measure tear production
• Measuring intraocular pressure with a tonometer

An accurate diagnosis can sometimes be made after physical and eye exams. In some cases, additional diagnostic tests may be recommended, such as:

• Bloodwork
• Bacterial or fungal cultures
• Ultrasound
• Cytology
• Biopsy

A definitive diagnosis of the type of eye infection as well as the location and underlying cause is needed to provide effective treatment. Different types of infections, eye conditions, and systemic diseases that produce ocular symptoms are treated differently.

How to examine your dog’s eyes at home

Examining your dog’s eyes at home can help you get a better idea of what’s normal as well as pinpoint the problem when they have symptoms. If it’s safe to do so, you can try these tips for examining your dog’s eyes:

1. Use a light and magnifying lens to look closely at the eye
2. Look for any obvious scratches or foreign items
3. Observe for swelling or irritation in any specific areas of the eye and surrounding tissue

Noting any recent exposure to smoke, air pollution, pollen, or other airborne irritants may be helpful to a vet. In addition, note any additional symptoms observed at home, such as sneezing, nasal discharge, lethargy, appetite loss, or other signs of illness.

Are eye infections emergencies?

Eye infections alone are not usually emergencies, but they can occur as part of a more serious medical condition. An obvious foreign body in the eye or an eye that’s been displaced from its socket (proptosis) are medical emergencies. Even if the eye issue is not an emergency, prompt treatment is highly recommended to determine the cause and to prevent the condition from getting worse. Untreated eye infections can lead to permanent eye damage, blindness, or even the loss of an eye. It’s always best to seek care as soon as possible for any eye issue. An online vet can help guide you through a home eye examination and help determine if emergency veterinary care is needed.

Proper treatment depends on the type of infection and any associated conditions. Treatment of the eyes may include:

• Eye drops or ointment with antibiotics, antifungals, antivirals, or anti-inflammatories
• Eyewash to remove irritants
• Oral medications, such as antibiotics, anti-inflammatories, or antivirals
• Pain medication
• Surgery

Administering eye drops at home in a non-stressful way can be challenging. An online vet can help walk you through administering eye medication so the experience is safe and comfortable for you and your dog.

In addition to treating the eye, an affected dog may need treatment for a systemic illness causing the eye symptoms. Treatment may include:

• Additional eye drops containing anti-inflammatories or immunosuppressants
• Allergy treatment
• Oral or injectable medication for associated conditions, such as diabetes mellitus or hypothyroidism
• Surgery

Some minor eye infections, caused by minor injuries or some viruses, may heal on their own or with supportive care. Supportive care to encourage eye healing may include:

• Keeping the affected dog indoors
• Applying warm compresses to the eye
• Higher heat and humidity in the dog’s environment

Always follow a vet’s instructions and advice about your dog’s treatment. It may be important to apply multiple topical eye medications in the correct order, and it’s always best to finish medications as instructed, even if symptoms go away quickly. Stopping treatment early may result in infectious agents that are resistant to medication, making the infection more difficult to treat. Never put anything in your dog’s eyes that is not approved by a veterinarian.

Can I treat my dog’s eye infection at home?

“It’s important to see a vet promptly for a proper diagnosis when a dog gets a red, runny, or otherwise inflamed eye,” explains Dr. Jo Myers, a veterinarian on the Vetster platform. “There are many eye conditions that have similar symptoms, so a dog’s symptoms may not be caused by an eye infection. In addition, knowing what type of infection a dog has is important for creating an effective treatment plan.” Viral, bacterial, fungal, and parasitic infections all have different treatment requirements. Eye infections in dogs are also often associated with other health conditions, so an accurate and thorough diagnosis is necessary to determine the treatment plan to treat not only the eyes but any other health issues as well.

Most canine eye infections are treated on an outpatient basis and rarely require hospitalization or surgery. Treatment often involves administering eye medication at home for multiple days or weeks and treating other associated health problems.

Do not attempt to treat your dog’s eye infection at home, remove a foreign body stuck in the eye, or push an eye that’s been displaced back into its socket. Without professional guidance, misdiagnosis is common, and improper treatment can result in more damage to the eye, risking blindness or even the loss of the eye.

Always consult a veterinarian if you observe changes in your dog’s eye health, even if those changes seem minor. If safe, examine your dog’s eyes for the source of the problem. Note any additional symptoms and whether your dog has been exposed to airborne chemicals or irritants, including pollen, dust, and heavy air pollution.

If your dog tolerates it and it’s safe to do so, apply a warm compress to the eye while waiting for a vet appointment. Cleaning eye discharge from the face can also help prevent skin irritation and make your dog more comfortable.

Do not attempt to treat your dog’s eye infection at home without talking to a veterinarian. You can talk to an online veterinary professional through the Vetster platform about your dog’s symptoms to help determine if emergency veterinary care is warranted.

Can a dog’s eye infection heal on its own?

Whether or not an eye infection can heal on its own depends on what’s causing it. Some minor eye infections or injuries can heal on their own or with minimal supportive care, while others require timely and appropriate treatment to prevent permanent eye damage, including blindness. Additionally, symptoms such as redness, swelling, and discharge from the eyes can occur with conditions other than infections, so it’s always best to talk to a veterinarian when you see any changes in your dog’s eye health.

Should I take my dog to the vet for an eye infection?

It’s important to seek veterinary care if you notice signs of an eye infection in your dog. An accurate diagnosis is necessary to determine if your dog’s symptoms are due to an eye infection or something else and to identify what kind of treatment will work. Misdiagnosis at home is common, and ineffective or improper treatment can lead to permanent eye damage, blindness, or even the loss of an eye.

How can I tell if my dog has an eye infection?

Common signs of eye infections in dogs include eye redness, red or swollen tissue around the eyes, eye discharge, squinting, and excessive blinking. Other eye conditions have similar symptoms, so it’s important to see a veterinarian in order to get an accurate diagnosis. In addition, eye infections can be caused by bacteria, viruses, fungi, or parasites, and treatment options vary depending on the type and location of the infection.

What does dog conjunctivitis look like?

Conjunctivitis is the inflammation of the conjunctiva of the eye, often caused by an infection, allergies, or irritants. The conjunctiva is a thin, clear membrane that covers the front of the eyeball and the inside of a dog’s eyelids. A dog with conjunctivitis often has redness and swelling of the pink lining around the eye, and their eyes may appear bloodshot. They may also have eye discharge and eye irritation that causes them to blink excessively, squint, or have trouble holding the affected eye open. Symptoms of conjunctivitis vary and can range in severity.