* Bacterial infection: This is the most common cause of pus in a dog's eyes. Bacteria can enter the eye through a scratch or other injury, or they can be spread from another infected area of the body.
* Viral infection: Viruses can also cause pus in a dog's eyes. Some common viral infections that can cause eye infections include canine distemper, adenovirus, and herpesvirus.
* Fungal infection: Fungal infections are less common than bacterial and viral infections, but they can also cause pus in a dog's eyes. Fungal infections are often seen in dogs with weakened immune systems.
* Allergic reaction: Allergies can cause a dog's eyes to become irritated and inflamed, which can lead to the production of pus. Common allergens that can cause eye infections include pollen, dust, and mold.
* Foreign object: A foreign object, such as a piece of dirt or a grass awn, can also cause pus to come out of a dog's eyes.
Treatment for pus in a dog's eyes will depend on the underlying cause. In most cases, antibiotics will be prescribed to treat a bacterial infection. Antiviral or antifungal medications may be needed to treat a viral or fungal infection. Allergy medications can be used to treat an allergic reaction. And surgery may be necessary to remove a foreign object.
If you notice that your dog has pus coming out of his eyes, it is important to take him to the vet right away. Early diagnosis and treatment can help to prevent serious complications.