PetMeds: Managing Eye Discharge (Mucus) in Dogs and Cats

Eye discharge is a common pet problem

A common concern of many pet owners is the presence of discharge in their dog’s or cat’s eyes. While this symptom is quite common, most of the time it is not significant and does not require medical treatment. The most common cause of discharge (often referred to as “eye crust”) is airborne allergens which can cause weepy eyes as in people. Other times, frequent eye discharge can indicate a clogged tear duct, although in this case the discharge is usually much thicker. Many times these mild discharges bother the owner more than the pet, and so I often advise clients to leave such issues alone.

When asked about eye discharge or mucus, I simply advise clients to wipe it away with a moist cloth or with some mild Visine eye drops. Most cases do not need veterinary attention and/or antibiotic therapy. However, if the discharge displays any of the below symptoms, then a veterinary exam would be recommended for proper diagnosis and treatment.

Symptoms to look for with eye discharge in pets:

  • Discharge becomes thicker
  • Discharge develops a green or yellow color
  • Discharge has a bad odor

Many pets with light-colored coats will often have dark staining under their eyes because of certain pigments in the tears and/or clogged tear ducts. As a result, clients will often ask about medications to reduce or eliminate the staining. The product Angels’ Eyes for dogs and cats works quite well; however, in the past this product has relied on the use of an oral antibiotic called Tylosin which in my opinion, if used long-term, can lead to imbalance of bacterial populations in the digestive tract and antibiotic resistance. Angels’ Eyes Natural Tear Stain Remover has since been reformulated without the use of Tylosin.

Many dogs develop conditions where their eyes don’t produce adequate tears, called dry eye, which can lead to a thick mucus buildup on the surface or cornea of the eye. I have found lubricants such as Puralube Vet Ointment and LiquiTears sometimes a more practical economic alternative to the more expensive Optimmune prescribed by many veterinarians.

If the above treatments do not help, or your pet’s eyes are severely red or light sensitive, it’s always best to have a veterinary exam to rule out more serious eye infections or ulcers. For simple infections or eye ulcers, I have found inexpensive prescription antibiotics such as Terramycin or B.N.P. Triple Antibiotic Ophthalmic Ointment to be as effective as some of the more expensive prescription drugs.

Due to the importance of the eyes and the potential for more serious eye conditions, if pet owners are ever in doubt, it is always best to have a proper eye exam by either a general veterinary practitioner or a veterinary ophthalmologist to rule out  more serious disease of the cornea.

Have pet health questions? For any medical concerns, we always recommend you consult your veterinarian. However, for non-emergency questions, you can contact Dr. Dym directly using our Ask the Vet form.

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  1. I have a 10 month old German shepard cross husky. I took him to the vet because his eyes very red with a little pus coming out every so often. The vet gave me ointment for conjunctivitis for 5 days. We finished the ointment on Friday and now his eyes aren’t red hut he has a lot of pus in the mornings almost filling his eyes. Not sure if it is caused by the ointment still or if there is another problem.

  2. I have a 2 month old pitbull mixed with stafordshire bull terrier yesterday in the morning i noticed he was sad i saw mucus coming out of both corners of his eyes he didnt wanted to eat till later and then wanted to play and all but i dont know if a piece of cheesecake affected him

  3. Dr. Michael Dym, VMD veterinarianMarch 19, 2016 at 4:59 pm

    I doubt the cheese cake affected him. Best to have vet exam and evaluation if signs persist or worsen, as lots of possibilities here.

  4. Dr. Michael Dym, VMD veterinarianMarch 19, 2016 at 5:58 pm

    Sounds like still an ongoing eye issue. BEst to return to vet for recheck exam of eyes, and probably best to see vet specialist or opthomologist on this one

  5. Hi
    I have a 9month old GSD x Mastiff
    She has very bad gooey eyes in the morning very thick stringy sometimes green in colour
    Her whites of her eyes are a tinge of brown and red around the edges
    I live in Australia and am unsure if it may be pollen related or maybe food allergy
    They dont bother her are not swollen
    Just bothering me more

  6. Both of these are possible as well as other inflammatory or allergic corneal diseases. She should have full vet exam and proper diagnosis

  7. Hi doctor, I have a Cavalier King Charles and pretty much since she was around 1 year of age she has had a stringy mucus in her eyes that I remove about every couple of hours. In the morning the strings are thicker. No odor or color. Would it be OK to use human artificial tears in her eyes? I have dry eyes and so I always have the tears on hand.

    Are the strings usually caused by dry eye? I didn’t think it was as her eyes are always wet looking and she has eye stains on her fur under her eyes.
    Thank you!

  8. I dont see a problem using the artificial tears, but you should still see your local veterinarian, as like you, your pet may have dry eye, which may need prescription topical medications such as tacrolimus or cyclosporine, etc

  9. My dog is a Mini Australian Shepard, and always has the occasional eye discharge, but the las two days it has dramatically increased. it seems to be a green/yellow color. Any idea what this may be?

    Thank you in advance for your help!

  10. Many possibilities from simple upper allergy to virus or bacterial infection. I would have vet exam and evaluation to see if prescription topical antibiotics needed.

  11. Hello i have a chiwawa and hes about 7 years old all of a sudden one eye is swoolen shut like a golf ball hes moving his neck werid crying loud if we get close to him i see a big blob of green puss justvhanging out of his eye looks likeva spider bite or a abcess he hides under the bed where i cant reach him i want to help him but im scarred he will bite me or i could hurt him. Or my other dogs will bumb him and he cries and growls loud

  12. HI Christina. With ANY sort of eye emergency, it is very important to have a physical exam ASAP as eye ulcers of cornea can be emergencies. I would go to vet as soon as you can

  13. Ok so this has been going on for a while and the vet has no idea what it is. Her eye has a reoccurring mucus that’s a pale shade a green. It covers her complete left eye, but she’s also blind in her left eye too. Her right eye is fine and has never had this problem, however. It doesn’t stop there though, because she has some sort of skin condition that even prescription steroids can’t fix, and we follow the amount we have to give her too. She’s always sleeping, and never goes out to play anymore, except to eat and drink water, as well as go to the bathroom. This has been occurring for possibly 2 years now, and when we tried to put her down so she wouldn’t be suffering anymore, our vet called it wrong and inhuman. She has several bald spots where she scratches herself until it bleeds, and no one has any idea what it is. If you have any idea at all it would help a lot. She’s almost 8-9 years old now. Thanks for reading.

  14. Try coconut or olive oil for her skin. It could be a form of excessive dry skin and either one will act as a natural deep conditioner. I wish I could tell u wht to do about the eye. I hate when one of my babies get sick. 2 or 4 legged.

  15. HI Barbara. Excellent suggestions regarding the coconut oil and olive oil. Often can be quite helpful

  16. Hello, My dog is over 10, small, and has a discharge freezing her littĺe eyes closed. She wakes-up in a panic, till i put water (warm) on her eyes to brake the hold of her discharge after it has hardened after sleep. This works for a while, then i have to put on the B.N.P.triple antibiotic ophthalmic ointment.That seems to take her thrugh the day till night again, then more ointment.
    Thank you for your inexspensive cure

  17. Hi DAle. Dont know if I have an inexpensive cure on this one. You need a definitive diagnosis of your dog’s specific eye condition for the best long term treatment here. I would go back to vet and have Schirmer tear test done to check for dry eye, which can appear like this, as well as fluorscein eye stain to see if scratch on cornea or ulcer. If dry eye or immune mediated condition of eye, then topical prescription drops like cyclosporine and/or tacrolimus may be needed here. You may want to ask your vet for referral to vet eye specialist in your area, fi you want expert opinion on this

  18. My brother in law has a lab that is completely blind in both eyes. For over a month now he has been having a thick mucus coming out of both his eyes but it’s worse in the left than the right. Also, sometimes the lower part of his eyes will droop and be very red. When this happens, he also has thick drool hanging from his mouth and his breathing seems to be heavy. Any idea what may be happening?

  19. HI Angie. This sounds like a very complex situation, given blind in both eyes, etc. The drooling and heavy breathing may have many causes, and without examining and evaluating dog in person, there are too many possibilities for me to give useful advice on this forum. I would recommend a full veterinary exam and evaluation. The drooping of the eye, and drooling could indicate a problem with what is known as the cranial nerves of the head, which could be part of the same disease that caused the blindness or not.

  20. My lab/standard poodle mix has chronic eye mucus. She has been tested for dry eyes and does not have it. Vet has treated her with Tobradex and Polymycin mix with steroid but the drainage always returns. She is seven and this has gone on for about a year. Her conjunctiva get red and the drainage is thick white to white yellow in color. She rubs her head against the furniture and bedding to try and remove it herself. I flush her eyes with artificial tears but it comes right back. Costly and frustrating.

  21. In my experience and opinion, even if your pet tested normal on Schirmer tear test, many of these pets still may respond to the topical dry eye medicines used, such as cyclosporine eye drops or tacrolimus eye drops, as most of these topical dry eye meds also often help with allergic and/or inflammatory/immune mediated eye conditions of the conjunctiva, etc, which you could ask your vet if these topical prescription eye meds may be appropriate . Also make sure your vet looks at underlying inhalent/contact allergies known as canine atopy, as this may be another reason why she rubs her eyes alot, etc leading to eye inflammation and discharge, and may need systemic allergy eye meds such as antihistamines, low dose cortisone or one of the newer oral allergy meds in dogs like Atopica or apoquel. Hope this helps. If this not helps, then consider asking your vet for referral to eye specialist in your area.

  22. Yes coconut oil all over dog was on drugs for years. It didn’t help made him sicker. I use only the coconut now his sink is great

  23. I have a pug who will be 5 in Oct…he was on and off steroids for about a yr…they didn’t help…he just got slightly chubby…he still kept scratching and chewing on himself…I MADE my vet do a full allergy test…turns out he’s highly allergic to everything including himself!
    Because his eyes stick out farther than the average dog…he gets sleepy boogies…today was the first day I noticed the boogies were a yellowish greenish color…I know it’s probably due to his massive list of allergies….
    I recommend telling ur vet to test for allergies…just by taking blood the test will show foods, things in house, outside, etc
    Hope all works out!

  24. Any thick green or yellow discharge from the eyes should always have proper vet exam for correct diagnosis and appropriate prescription medication whether topical antibiotic or topical antibiotic/steroid combination. For your pet Crystal, I would also ask your vet about newer prescription meds for allergies such as apoquel or the new injection known as ADI or Cytopoint. Blood tests for food allergies are not considered accurate by most veterinary dermatologists so I would not waste money or energy testing for food allergies. I am also not fan of having local vets test for airborn contact allergies known as atopic allergic disease, as these tests are often difficult to interpret, based on which lab is used and the specific allergens you have in your area. Best in my opinion to have these tests done by proper veterinary dermatologist, Gold standard for allergy testing is still considered skin testing by most veterinary dermatologists

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