Conjunctivitis in dogs, commonly called “dog pink eye”, is an inflammation of the conjunctival membrane and soft tissues surrounding the eye.
The conjunctival membrane surrounds and covers the surface of the eyeball, up to the cornea. It also extends into the back of the eyelids.
The membrane protects and shields the eyeball and holds the eyeball in place. It also ensures that the eyeball remains properly lubricated at all times, through the distribution of tears and moisture.
In short, the conjunctival membrane plays an important part in the overall wellbeing of a dog’s eye.
Conjunctivitis occurs when there is a buildup of harmful matters (e.g. bacteria, irritants) on the conjunctival membrane.
The buildup disrupts normal eye functioning. Specifically, it impairs the proper functioning of the tear ducts and other specialized cells responsible for creating moisture. As a result, the eye becomes dry and scratchy.
If your dog has a red eye with discharge but without showing any pain, he may have conjunctivitis.
The eye discharge as a result of dog conjunctivitis may be clear and watery. Or, it may be mucus-like, or pus-like, depending on the cause of conjunctivitis.
Causes of Canine Conjunctivitis
Common possible causes of conjunctivitis in dogs include:
Irritants or Allergens (Allergic Conjunctivitis)
Physical irritants and allergens are possible causes of canine conjunctivitis. (Some such irritants include dust, small bugs, and debris. Allergens can be insect bites, or food ingredients.)
Dogs with allergic conjunctivitis usually have clear watery discharge and the affected eye is itchy.
Bacteria (Bacterial Conjunctivitis)
Sometimes inflammation of the conjunctival membrane can develop into a full-blown bacterial infection.
The most common bacteria responsible for bacterial conjunctivitis are Streptococcus and Staphylococcus. Eye discharge as a result of bacterial conjunctivitis contains mucus and pus, and the conjunctiva is red and swollen.
Sometimes the eyelids may become crusted due to the thick secretions. When bacterial infection occurs behind the eyelids in a newborn puppy, the result is called neonatal conjunctivitis.
It occurs when bacteria get to the space behind the eyelids during or shortly after birth. The puppy’s eyelids are swollen and there may be a pus-like discharge if the eyes are beginning to open. Sometimes the discharge can cause the eyelids to stick together.
If you suspect neonatal conjunctivitis in your puppy, consult your vet immediately because delay in treatment can lead to blindness.
Symptoms of Canine Conjunctivitis
Besides the hallmark symptoms of eye discharge and redness, canine conjunctivitis can also cause a dog to paw at the affected eye, and rub his face against the edge of furniture or on the floor due to itchiness and irritation.
Also, conjunctivitis causes the affected eye to become more sensitive to light, so the dog may squint and may avoid going outside during the day. He may seem to be more lethargic and may sleep more.
Treatment of Canine Conjunctivitis
Treatment of canine conjunctivitis depends on the underlying cause of the infection.
A mild case of conjunctivitis with watery discharge caused by irritants, for example, responds well to home remedies.
Simply flushing the eye several times a day with a sterile saline eyewash should do the trick. You may also want to use a soft cloth to wipe the area around your dog’s eye to remove any eye discharge and any dirt or foreign materials.
Alternatively, use a gentle natural eye wash to clean and remove gunk in and around a dog’s eyes:
However, for more serious cases such as bacterial conjunctivitis, veterinary treatment is necessary.
The vet will first remove the secretions and crusts from the eyes and will then usually apply topical antibiotics to the infected eye. You will be instructed to do the same at home for several days beyond apparent cure.
Prevention of Canine Conjunctivitis
As always, prevention is better than cure! You can try to prevent conjunctivitis in your dog by doing the following:
- As much as possible, avoid exposing your dog to environmental allergens and irritants.
- Prevent your dog from fighting with other dogs (or cats).
- Keep your dog’s eyes clean. Remove gunk from the corners of the dog’s eyes.
- If your dog has long facial hair, trim the hair shorter as that it won’t get into the eyes.