Dog Eye Discharge

Dog Eye Discharge

When thinking of certain breeds of dogs, a droopy-eyed Saint Bernard or weepy-eyed Shih-Tzu may come to mind. But when is dog eye discharge something more serious? Perhaps you’ve noticed your dog’s eyes tearing up more often than usual. Or, their normally clear eye gunk is now a strange shade of green. Read on to learn more about what both the symptoms surrounding and color of your dog’s eye discharge may mean.

What Is Dog Eye Discharge?

Eye discharge is the leaking of fluid from the eyes. In healthy eyes, it is normal for this fluid to help lubricate the lens and cornea. This keeps the eye from drying out and keeps it functioning normally. The fluid then drains into your dog’s tear ducts, located at the base of the eye closest to their nose. The fluid is then reabsorbed, or mixed in with your dog’s nasal fluids. With normal functioning, you may see minimal tearing as your dog blinks. However, in the case of something wrong, this tearing may become excessive, change to a strange color, or disappear completely, drying the eye out.

General Signs to Watch Out For

While some tearing of the eye is a normal body process, excessive eye discharge in dogs is a concern. If you notice your dog’s eyes seem to be “leaking”, are draining more than normal (or not at all), or the discharge becomes an odd color, it is a sign for concern. Discharge that is green, yellow, or cloudy can indicate the presence of infections from viruses or bacteria.

Excessive discharge along with swelling of the eye can also indicate irritation or inflammation. Lastly, if you notice your dog seems to be rubbing their face on things more often, it could indicate they’re feeling itchy or painful.

Dog Eye Discharge — Causes

Below are some of the most common causes behind eye discharge in dogs — normal and not:

Normal Tear Staining

One of the most common types of eye discharge in dogs is tear staining. All dogs experience normal tear staining and tear production. However, some breeds, especially light or white-furred ones, may have tear staining that is more noticeable. Tear staining occurs when there is a chemical reaction between the body’s natural tears and the fur itself. This is normal, and not at all harmful to your dog aside from cosmetically looking messy.

All dogs experience tear staining to some degree. However, flatter-faced or light-haired dogs may have a more noticeably large patch of staining. As long as the stain or discharge is not green, yellow, or blood-tinged, the eye is not inflamed or red, and your dog is not rubbing their face, nothing further needs to be done. There are several products on the market that can be used to safely remove the stains around your dog’s eyes to give them a brighter, cleaner appearance. These are available over the counter from most pet stores and retailers.


Another common cause of eye discharge is allergies. Allergies can either be environmentally related or food related, though eye discharge is more common with environmental allergies. Signs of allergies include copious amounts of clear or slightly cloudy discharge. Your dog may also sneeze, have clear nasal discharge, have red or itchy eyes, or have other redness or swelling on the face and body. In the case of systemic allergies, the entire body may break out in red rashes or welts.

Allergies are often first diagnosed and treated with conservative methods. This may include a symptoms check from your vet and a daily over the counter allergy medication, such as Benadryl, to see if symptoms improve. From there, your vet may recommend additional testing such as bloodwork to rule out systemic issues, avoidance of potential irritants or food ingredients, and stronger allergy medications. For longer-term relief, medications such as Claritin and Zyrtec have shown good results in dogs. Prescription medications such as Atopica and Apoquel can also help reduce allergy symptoms.

If your dog has environmental allergens to things such as dust, grass, or pollen, a few things can be done to help reduce symptoms without medications. Be sure to keep your dog in a well-ventilated area that is dust-free and vacuumed regularly. Keeping them away from areas of the house where you are actively cleaning can also help. When coming in from the outdoors, a pet wipe or baby wipe can be used to wipe down the face, belly, and paws to prevent pollen and grass allergens from sticking to the fur and causing irritation.

Chemical Irritants

If you notice your dog’s eyes tearing up after you’ve cleaned the house or used a new perfume, you may be noticing the effects of chemical irritants. Just like people, chemicals can be harmful to pets and can cause eye discharge among other symptoms. Signs to look out for include clear draining of the eyes, runny nose, redness or swelling of the eyes, sneezing, coughing, or trouble breathing.

If you notice your dog is having trouble breathing, move them to a well-ventilated room immediately and discontinue use of the item. If they do not recover within several minutes, are turning pale or blue, or are struggling to breathe, this is a toxic reaction that requires emergency care.

Many items can cause chemical irritation in dogs. The most notable are bleach or ammonia-based cleaners. Perfumes and essential oils can also be harmful to dogs, especially if used in diffusers or placed directly onto your dog’s body. It is best to move your dog to a different room before using a cleaner or diffuser. Be sure to ventilate the room completely, and make sure your dog does not have access until the room is free of scents.


Dog Eye Discharge Infections can present with a variety of symptoms, including eye discharge. This can occur in both respiratory-related infections, and sometimes systemic infections. In most cases, the key indicator of an infection is the strange color of the discharge. It can appear thick, green, yellow, or cloudy. Often, it will lead to crusting of the eye, sealing the eye shut. This discharge can also cause irritation including redness and swelling of the eye, eyelid, and tear ducts. In addition, your dog may also become lethargic or feverish, cough or sneeze, lose their appetite, or have other symptoms more specific to the type of infection.

Your veterinarian can help you determine if your dog has a respiratory infection. Most infections are secondary, often in addition to a viral infection such as Bordetella (Kennel Cough), Distemper, or other illnesses. However, some infections can be primarily caused by bacteria, such as the bacterial form of Bordetella. Blood work can help rule out systemic illness in addition to X-rays of the heart and lungs as needed.

Depending on the cause, treatment can vary. Antibiotics can help treat bacterial primary and secondary infections, while palliative care can help treat underlying viral illnesses. If your dog is severely ill, your vet may recommend hospitalization with IV fluids and medications until they are stable enough to go home. Most respiratory infections will resolve in 1 to 2 courses of antibiotics, however, in some cases, long-term care is needed.

It can be hard to prevent an infection. However, regular preventive care such as vaccination, and keeping the eyes clean and dry can help reduce severity and discomfort. A warm washcloth or compress can help open up crusty eyes and relieve pain and pressure.

Chronic Dry Eye (Keratoconjunctivitis sicca)

Chronic dry eye seems counterproductive to the topic of eye discharge. However, it can actually be a major cause behind it. Otherwise known as keratoconjunctivitis sicca, or KCS, this type of eye issue can lead to gray, sticky, clay-like discharge from the eye. As the eye fails to produce enough tears to keep it lubricated, it will often start to overcompensate. This leads to excessive tearing. However, since the tear ducts and ability to produce tears themselves are affected, the discharge will often have a sticky, gray appearance.

KCS is caused by an immune system reaction. This leads to the body attacking its own tear ducts and tear production centers. In addition to strange eye discharge, you may notice your dog blinking or rubbing their eye more often. The eye or cornea may get a dry or cracked appearance, and the eye may be red or painful for your dog. This is a serious problem that requires care, otherwise, the eye can be damaged to the point of blindness or needing to be removed.

Your vet will perform a test called a Schirmer Tear Test. A special paper filter is placed beneath your dog’s eyes. The eyes are then held closed for 5-10 minutes to collect tears. If the paper is not very moist, or not moist at all after this time, it is an indicator of not enough tear production. Treatment involves daily applications of artificial tears, Atopica to reduce the immune response, or other similar medications. In severe cases, surgery may be needed but is rare as most dogs respond well to daily medication.


Conjunctivitis, or inflammation of the conjunctiva (the membrane that lines the eyes and eyelids), can lead to a variety of symptoms, including eye discharge. You will also see symptoms such as swelling or redness around the eye, the eyelids, or discoloration of the eye itself. In severe inflammation, the third eyelid may remain permanently covering the eye, instead of returning beneath the eyelid as normal. Conjunctivitis can affect one or both eyes, however, it is most commonly seen in both eyes at once.

Several things can lead to conjunctivitis, as it is more of a general term than a diagnosis. Viral illnesses, immune-mediated inflammation, tumors affecting the eyes, obstructed tear ducts, parasites, nutritional deficiencies, and more are all potential causes. Because of this, a complete exam and workup by your vet is best.

Your vet will likely start with a visual examination of the eye to look for injury or tears to the eye or eyelid. Fluorescein stain tests can be used to determine this. Blood work is also beneficial for ruling out systemic issues such as immune disorders, infections, and viruses. In severely affected eyes, a referral to a veterinary ophthalmologist may be needed.

Treatment involves treating both underlying conditions, and the inflammation itself. Your vet may recommend systemic antibiotics, steroids, or pain medications. In addition, medicated eye drops and ointments can be used to reduce swelling and pain directly in the eye.

Injury to the Eye

You may think injuries to the eye are easily visible, however, they may be hard to see, especially if the injury is caused by items such as sand, dust, or small debris. If you notice your dog has a large amount of clear or cloudy discharge, their eye is red or swelling, or they seem to be keeping it closed, an injury may be to blame. You may also see blood-tinged discharge, visible items in the eye, or visible wounds.

It is best to bring your dog to your vet right away if you suspect an injury. The sooner your vet can remove or flush the item causing the injury, the faster the eye will recover and the less overall damage there will be to repair. Your vet can examine the eye to look for debris, either with a general visual inspection, ophthalmoscope, or fluorescein stain. From there, your vet may recommend sedation in order to safely remove or flush the debris from the eye. If the eye is badly injured, surgical repair of the eyelids, or removal of the eye itself may be needed.

After treating in the clinic, your vet can send you home with a number of medications. Pain medications and steroids, given either orally or directly in the eye, can help reduce pain and swelling. Antibiotics may be given if there is an infection present or it is suspected that the injury may lead to one. Your vet will also recommend an Elizabethan (cone) collar. This will keep your dog from rubbing or pawing at the eye, which can reduce further inflammation and infection.

Monitor your dog in places they are likely to get injured. Wearing protective gear, such as goggles, when on carts, motorcycles, or bikes can help.

Tear Duct Blockage

Tear duct blockages can happen in two ways. One is a blockage from where the tear duct opens at the eye. The other is where the duct exits within the nasal passages. If the duct by the eye is blocked, such as by thick discharge, tumors, or swelling, you may notice your dog having excessive tearing, pain upon opening or closing the eye, or a visible swelling at the eye’s corner. If the end of the duct is blocked, such as by tumors, nasal discharge, or nasal congestion, you may notice your dog sniffling, snorting, or sounding congested.

Dog Eye Discharge In both cases, you will likely see an uptick of clear discharge, though it can be discolored if the underlying cause is due to viral or bacterial infections. Your vet may recommend basic tests such as visual exams and scoping of the nose. Or, they may order more extensive testing such as X-rays or a sedated scope of the nasal passages or blood work to look for underlying illness.

Treating the underlying cause of the blockage is best. In the case of illness, medications can help reduce swelling and symptoms. For tumors, removal of the tumor can help clear up the blockage. In some cases, the eye discharge and blockage may become chronic. This requires frequent cleaning of the eye to help keep it clear and open.

Eyelid Irritation (Entropion, Ectropion, Cherry Eye)

Functional disorders of the eyelid can lead to excessive tearing and eye discharge. Entropion and ectropion both affect the main eyelid, causing it to either bend inward or outward. Inward (Entropion) bending of the eyelid leads to irritation from the eyelashes, causing the eye to tear up, get red, and even swell. Outward (Ectropion) bending of the eye usually leads to excessive dryness, however, the eye may overcompensate by producing more tears, leading to excessive eye discharge. Cherry eye affects the third eyelid and may cause the eyelid to stick out at all times, causing irritation, excessive eye discharge, and swelling.

Luckily, all of these issues can be treated; usually with basic surgery by your veterinarian. Your vet will first examine the eye to see what is happening with the eyelid. From there, they can surgically repair the eyelid. With cherry eye, the third eyelid is tacked back into place, helping with the weakened ligament. For Entropion and Ectropion, the eyelid is often sutured shut for several weeks. This allows the eyelids to reposition back into their normal positions, while allowing the eye underneath to heal. Once the eyelids are back to normal, the sutures are removed.

In addition to surgical correction, eye drops can help. They keep the eyes lubricated and reduce swelling and inflammation. Pain medications and antibiotics may also be recommended. In most cases, surgical repair has excellent prognosis and the area is healed fully in 3-4 weeks.


Glaucoma is the increase in pressure of the eye. It can be genetic in origin, and can come on either slowly or rapidly. It leads to a myriad of problems, including eye pain, swelling, clouding of the eye, and loss of vision. Major symptoms include bulging and clouding of the eye. You may also notice excessive eye discharge in one or both eyes. Symptoms may be hard to notice at first. This is true if your dog compensates by other means, such as sound or scent.

A tonometer can be used to measure the pressure of your dog’s eye, in addition to visual inspection. From there, your vet can recommend medications. These will help reduce swelling and inflammation and increase the draining of fluid from the eye to reduce pressure. In severe cases, your vet may recommend a referral to a veterinary ophthalmologist. Glaucoma is often progressive and requires lifelong treatment. In severe cases, removing the eye may be the best option to reduce pain and further deterioration.

Breed Predisposition

While breed predisposition isn’t a disease in itself, it is important to know if your dog’s breed or breed mix may expose them to higher chances of eye problems. Eye discharge can be normal, as seen with tear staining in white or light-coated breeds. Some breeds, such as flat-faced breeds like Pugs, Boston Terriers, and Bulldogs, may have a higher incidence of issues such as cherry eye or tear duct blockages. Other breeds, such as terriers, poodles, and Beagles, have a higher incidence of glaucoma.

Knowing your dog’s breed history can help you prevent eye issues before they become a major problem. Regular veterinary check-ups of the eyes in glaucoma-prone breeds can catch it in the early, treatable stages. Carefully select and breed dogs. Those that don’t have a history of illness, or that have slightly longer snouts can help reduce the chances of functional issues of the nose and tear ducts. Your vet and breeder can work with you to help keep your dog healthy, and watch out for any problems in their line they may be predisposed to.

Eye discharge in dogs has many causes, from the normal to the serious. Knowing your dog’s regular amount of eye discharge can help keep you in the know for when things aren’t normal. Inspect your dog’s eyes daily. Cleaning any goop can keep the eyes healthy, and alert you to problems before they progress. Luckily, most eye discharge issues are treatable with a trip to your vet.

Dog eye discharge is the body’s way to self-cleanse and get rid of impurities and dirt trapped inside the eye. It may, however, be a sign of a more serious health problem such as an infection. On a good note though, most cases will clear with simple home remedies but if that doesn’t help, you or your vet may resort to one of the various medical treatment options as discussed herein.