What is epiphora?
Epiphora means an overflow of tears from the eyes. It is a symptom rather than a specific disease and is associated with a variety of conditions. Normally, a thin film of tears is produced to lubricate the eyes and the excess fluid drains into the lacrimal or tear ducts, which are located in the medial canthus or corner of the eye next to the nose. The tear ducts drain tears into the back of the nose and the throat. Epiphora is most commonly associated with insufficient drainage of the tear film from the eye. The most common cause of insufficient tear drainage is a blockage of the lacrimalor tear ducts. Epiphora may also result from the excessive production of tears.
What are the clinical signs of epiphora?
The most common clinical signs associated with epiphora are dampness or wetness beneath the eyes, reddish-brown staining of the fur beneath the eyes, odor, skin irritation and skin infection. Many owners report that the dog's face is constantly damp, and they may even see tears rolling off their pet's face.
How is epiphora diagnosed?
The first step is to determine if there is an underlying cause for the excess tear production. Some of the causes of increased tear production in dogs include conjunctivitis (viral or bacterial), allergies, eye injuries, abnormal eyelashes (distichia or ectopic cilia), corneal ulcers, eye infections, anatomical abnormalities (entropion or ectropion) and glaucoma.
Once the more serious causes for epiphora have been eliminated, it is necessary to determine if proper and adequate tear drainage is occurring. A thorough ocular examination is performed, paying special attention to the tear ducts and nearby tissues, and looking for signs of inflammation or other abnormalities. The facial anatomy of the dog may play a role in this condition. Some breeds have flat or "squished-in" faces that do not allow the tear film to drain properly. In these patients, the tear film fails to enter the duct and simply rolls off the face. In other cases, the hair around the eyes physically obstructs the entrance to the tear ducts, or debris or a foreign body forms a plug within the duct and prevents drainage of tears.
One of the simplest tests to assess tear drainage is to place a drop of fluorescein stain in the eye, hold the patient's head slightly downward, and watch for drainage into the nose. If the drainage system is functioning normally, the eye stain should be seen in the nose within a few minutes. . Failure to observe the stain doesn't definitively diagnose a blocked lacrimal duct, but it does indicate the need for further investigation.
How is epiphora treated?
If the lacrimal duct is suspected of being blocked, the dog is anesthetized and a special instrument is inserted into the duct to flush out the contents. In some cases, the lacrimal puncta or opening may have failed to open during the dog's development, and if this is the case, it can be surgically opened during this procedure. If chronic infections or allergies have caused the ducts to become narrowed, flushing may help widen them.
If the cause is related to another eye condition, treatment will be directed at the primary cause.
What can I do for the staining?
There are many remedies that have been recommended for removing or eliminating the facial staining associated with excess tears. None of these has proven to be 100% effective. Some over-the-counter treatments may be harmful or injurious to the eyes. Hydrogen peroxide can seriously injure the eyes.
Treatments that may lessen tear staining in some cases include:
- Parsley or parsley flakes - add a small amount to the diet
- Low doses of doxycycline, tylosin, tetracycline or metronidazole. These treatments are no longer recommended due to the risk of developing bacterial antibiotic resistance, rendering these valuable antibiotics worthless for human and veterinary use
- Cleaning the area daily with MalAcetic® wipes
- Cleaning the area with Diamond Eye® or a similar product
- Missing Link® nutritional supplements - the manufacturer claims their products reduce tearing and tear staining in three to four months
Do not use any product without consulting with your veterinarian.
What is the prognosis for epiphora?
Unless an underlying cause can be found and treated, most patients with epiphora will experience intermittent episodes throughout their life. If the dog's facial anatomy prevents adequate drainage of the tear film, it is likely that some degree of epiphora will persist despite all treatment efforts. Your veterinarian will determine the specific treatment options and prognosis for your dog.