By Jennifer Copley (Last Updated 6 December 2011)
There are various illnesses and other problems that can cause red, bloodshot eyes in cats, including:
- Bacterial, fungal, and viral infections such as feline herpes virus (cat flu) and feline immunodeficiency virus (FIV)
- Blepharitis (eyelid inflammation) due to allergies, parasites, infection, or other causes
- Conjunctivitis (inflammation of the membranes that line the eyelids, often due to infection)
- Corneal ulcers
- Environmental irritants (mold, dust, pollen, grass, smoke, chemicals, etc.)
- Eyelid tumour
- Hemorrhage in the eye
- Injury to the eye or eye area
- Keratitis (inflammation of the cornea)
- Object stuck in the eye or under the eyelid
- Orbital disease
- Problem with the nictitating membrane (third eyelid)
- Uveitis (inflammation of the eye’s inner vascular layer including the iris and related structures)
Additional eye-related symptoms may include:
- Cloudy-looking eyes
- Eye discharge (runny or crusty eyes)
- Increased blinking
- Nictitating membrane (third eyelid) partway or all the way across the eye
- Rubbing the eye
- Vision problems
If the problem is a systemic illness rather than one that just affects the eye, there may be additional symptoms such as lethargy, weight loss, lack of appetite, diarrhea, or vomiting.
Treatment varies depending on the underlying cause of the bloodshot eyes. In the case of systemic illness, oral medications such as antibiotics or other treatments may be required. If the problem affects only the eye, it’s often treatable with eye drops or ointments, though certain eye problems necessitate oral medication or even surgery. If environmental irritants are the trigger, simply removing the irritant to which the cat is sensitive should solve the problem.
If a cat paws at his eye while recovering from an eye problem, he may need to wear an Elizabethan collar to protect the eye until it’s no longer irritated, painful, or itchy.
Don’t administer any eye drops other than those prescribed by a veterinarian. Eye drops designed for humans are unlikely to provide benefits and may even harm your cat. Even if human eye drops do reduce the redness, they will simply mask a problem that requires treatment and make it difficult for the veterinarian to make a diagnosis.
How to Administer Eye Drops to a Cat
The easiest way to administer eye drops to a cat is to wrap him in a towel and lay him on your lap or another surface. Lay an arm lengthwise along his body with your hand close to his head so that you can hold his head still and simultaneously use your thumb to hold his eye open. With your other hand, hold the eye drops 2 centimeters above his eye and drip the prescribed amount into the lower part of the eye.
This article is provided for informational purposes only and is not intended as a substitute for veterinary consultation and care.