- Eye infection (bacterial or viral): A common cause of discharge from the eye is an eye infection. Bacterial and viral infections can cause the eye to produce a thick, snotty mucus to protect itself from the infection.
- Allergies: Allergies can also cause snotty mucus to come out of a dog's eye. When a dog is exposed to an allergen, their immune system releases histamines, which can cause the eyes to produce mucus.
- Dry eye: Dry eye, or keratoconjunctivitis sicca, is a condition where the eye does not produce enough tears to keep it lubricated. This can cause the eyes to become irritated and produce a snotty mucus.
- Trauma: Trauma to the eye can also cause snotty mucus to be produced. This can be caused by a foreign object getting in the eye, such as a piece of dirt or grass.
- Underlying medical conditions: Some underlying medical conditions can also cause snotty mucus to come out of a dog's eye. For example, certain autoimmune disorders can affect the eyes and cause them to produce mucus.
- Conjunctivitis (Pink Eye): Infectious conjunctivitis is characterized by redness, swelling, and discharge which may resemble mucus or pus.
If your dog is experiencing snotty mucus coming from their eye, it is important to take them to the vet for diagnosis and treatment. The vet will be able to determine the cause of the mucus and recommend the appropriate course of treatment.