Here are a few possible causes of a red eye in a 14-year-old dog:
- Corneal ulcer: A corneal ulcer is a break in the clear outer layer of the eye. It can be caused by trauma, such as scratching, biting, or exposure to foreign objects, or it can be a result of underlying medical conditions.
- Conjunctivitis (pink eye): Conjunctivitis is inflammation of the conjunctiva, the membrane that lines the eyelid and covers the white part of the eye. It can be caused by allergies, infections (bacterial, viral, or fungal), or irritants.
- Glaucoma: Glaucoma is a condition in which the pressure inside the eye increases. It can lead to damage to the optic nerve and vision loss.
- Uveitis: Uveitis is inflammation of the uvea, the middle layer of the eye that contains the iris, ciliary body, and choroid. It can be caused by various underlying medical conditions, including autoimmune diseases, infections, or trauma.
- Dry eye: Dry eye occurs when the eye doesn't produce enough tears. It can be caused by various factors, including age-related changes, certain medications, or underlying medical conditions.
- Cherry eye: A cherry eye is a condition in which the tear gland protrudes from the corner of the eye near the nose. It can occur due to a weakness or defect in the tissue that holds the gland in place.
It's important to note that a red eye can be a sign of a serious medical condition, and it's essential to seek veterinary care as soon as possible to ensure your dog receives appropriate treatment. The veterinarian will perform an eye examination, including assessing the cornea, conjunctiva, iris, pupil, and lens, to determine the cause of the redness and recommend the appropriate course of treatment.