Canine Epiphora
Tear Staining
Epiphora is excessive tearing. Extra tearing from time to time is normal, but if it is constant, you should visit your veterinarian as soon as possible. All that moisture can cause pain, infection, and staining (tears have no color, but they dry into a red, brown, or black crust, which will stain your dog's hair and face).
The staining itself is not a medical problem; it just does not look nice.
Eventually, it may cause vision loss. For some breeds, epiphora is not harmful.
CAUSES:
1) Irritation to the eye: The eye's normal response to irritation is to produce extra tears to flush it away. An overproduction of tears overwhelms the drainage system.
Examples of irritants (can be a foreign object or an irritation in the eye):
- Hair: eyelashes growing at abnormal angles or eyelashes growing on the inner surface of the eyelids
- Particles in the air: dust, chemicals, or smog
- Cornea damage: inflammation or scratches of the cornea (the outer covering of the eye)
- Glaucoma: raised pressure in the eye
- Anterior uveitis: inflammation of the middle layer of the eye
- Scarring: around the eye after surgery
2) Abnormal tear drainage: In a healthy eye, tears flow through the puncta (a tear duct located in the inner corner of the eye near the nose) that drains the tears into its nose and throat. Problems along this route can cause epiphora.
- Shallow eye socket: tears overflow from the eye because there is not enough space in the eyelid for them. The tears do not enter the tear duct but spill down the sides of the nose
- Eyelids turned inward: this blocks the opening to the tear duct (called the puncta)
- Long hair draws tears from the eye to the skin. Your veterinarian can trim this hair and may recommend surgery to change the skin fold
- Old infections or injuries: may scar the opening of the ducts closed. Sometimes a saline flush through the ducts can re-open them
- The dog is born with closed puncta: your veterinarian can do surgery to open them
3) Overactive tear glands (least common)
SIGNS:
- Stains under the eyes and near the nose
- Constant wetness around the eyes
- Crust around the eyes
- Swollen eyelids and face
- Excessive blinking and squinting (due to pain)
- Rubbing eyes and face
- Red and or cloudy eyes
- Change in pupil size, and then vision loss
If your dog is showing any of these signs, this is an emergency and you should visit your veterinary clinic right away. It is especially important if the signs occur suddenly.
DIAGNOSIS:
Your veterinarian may perform some tests to rule out other diseases. A corneal stain, (a fluorescent dye placed in the eye), can test for ulcers. Your veterinarian may also test your dog's eye pressure to see if it has glaucoma.
Your veterinarian will perform the following procedures to test for epiphora:
- Complete eye exam: a magnified examination of the eyelids, tear duct openings, cornea, etc.
- Dacryocystorhinography: flushing of the entire tear duct system with a liquid that will show up on x-rays. This shows the tears draining from the corner of the eye all the way to the nose and can point to any blockages
- Schirmer tear test: your veterinarian will put a strip of paper into the lower eyelid, which changes colors as tears fall on it. This checks if tear production is below average, average or excessive
TREATMENT:
- Medication: to clean the stains
- Antibiotics: if there is an infection
- Surgery: to repair tear ducts or eyelashes, or to remove blockages
PREVENTION:
Most of the time, you will not be aware of your dog's condition until you start to see signs of epiphora, so there is no way to prevent it.
To prevent a relapse, wash and dry around their eyes daily using lukewarm water and a soft cloth.
PROGNOSIS:
There is a good prognosis for dogs that get quick medical attention and treatment. Delaying treatment may lead to blindness.
Medically Reviewed by Sara Ochoa, DVM
