We get a lot of questions about how to stop the tear staining on dogs, especially small light-colored dogs like maltese and shih-poos. Turns out it’s called epiphora, and it happens exactly why you would think: chronic overflow of tears onto the dog’s face. It can be caused either by excessive tear production, or inadequate tear drainage. Epiphora can be acute or chronic, but the staining issue we see at the shop is a result of the chronic form. Tears are the eye’s natural attempt to flush away anything causing irritation, such as dust or pollen. When excessive tearing becomes chronic, the constant moisture irritates the skin and breeds bacteria and yeast which will cause the dog to rub his eyes and irritate them even more. Eventually the condition results in red staining due to accumulation of pigment found in their tears.
Sometimes epiphora is a problem not with making tears but with getting rid of them. Normally tears exit the eye through small holes that go into the nasolacrimal duct, which drains into the nose. If this duct or the small holes draining into it are blocked by swelling from irritation then the tears cannot drain properly. Some breeds may have a genetic abnormality of the small holes in the eyelids which drain into the nasolacrimal duct which will also cause the tears to back up.
Your first step should be to see your regular veterinarian. They will examine the eye to make sure there is nothing actually in the eye irritating it. Some other things they will look for are when an eyelash grows into the cornea instead of out from the eyelid. This is common in some small breeds. They will check for other causes of excess tear production such as conjunctivitis or glaucoma. Your vet can also check the drainage by using a dye and watching where it goes.
Obviously the appropriate treatment depends on finding out the real cause. If the main culprit for your dog is inflammation and irritation of the soft tissues, then you will need to get that under control to stop the staining.
In the meantime, keeping the hair around the eyes clipped short will help keep the skin clean and dry, and allow you to clean it regularly with a warm washcloth to prevent bacteria and yeast from growing.
Hope this article helped explain where the heck that red gunk comes from and why. And don’t forget, we trim eyes and wash faces here if you need some help!