Why Are My Dog's Eyes Red?

Is the eye redness accompanied by dryness?

Is your dog pawing at the affected eye or eyes due to the discomfort?

Is there a cherry-like tissue in the corner of your dog's eyes?

Is the eye redness accompanied by visible swelling?

Did your dog suffered an eye injury?

Is your dog allergic to any type of food or pollen?

Dry eye occurs when the eyes don’t produce enough tear film. Without tears to keep the cornea moist and free from debris or infectious agents, the cornea becomes dry and inflamed. This inflammation is quite painful and makes the eyes look red. Dry eye has many causes, the most common of which is immune-mediated adenitis, which damages tissue responsible for forming the watery portion of the tear film.

Pink eye or Conjunctivitis occurs when the conjunctiva — the moist, pink tissue that lines the inner eyelids and front of the eyes — becomes inflamed. This inflammation causes redness. Environmental irritants like dust and pollen can cause pink eye. Pink eye typically affects one eye at a time.

Dogs have a third eyelid that normally stays hidden. Some dogs have a genetic disorder that weakens the ligaments holding this eyelid in place, causing the eyelid to pop up and look like a cherry in the inner corner of the eye.

Glaucoma, a fluid build-up in the eye that creates pressure which, if not alleviated, can cause blindness. Redness caused by glaucoma is accompanied by visible swelling. Time is a critical factor for treating glaucoma, which is why a dog showing signs must see a veterinarian immediately.

Scratch or foreign object in the eye can be the cause of corneal damage. Anything that can damage a dog’s cornea can cause eye redness. For example, if your dog is running through tall grass, a grass stalk can poke your dog’s eye and cause damage and irritation.

Allergies can have many different symptoms, one of which could be red, teary eyes in dogs. Talk to your veterinarian about how to alleviate your dog's problems with allergies.

Uveitis is an inflammatory process involving the middle of the three layers in the eye. The eye may appear dull, cloudy, or red due to changes in the cornea or due to inflammatory cells accumulating inside the eye. Uveitis must be treated readily to prevent glaucoma. Take your dog to the vet as soon as possible.