Effective Treatment will Eliminate Pain & Preserve Eyesight
My elderly cat has red rimmed crusty eyes. What causes this and how do I treat?
Your kitty is really uncomfortable. Cats whose tear glands fail in their job of keeping the eyes moist have dry eye, also called keratoconjunctivitis sicca (abbreviated KCS). It’s somewhat unusual in cats but common in dogs.
KCS is a serious problem. Symptoms can go well beyond chronic redness and a pus-like discharge. Many squint and have swelling of the third eyelid. The membranes beneath the upper and lower eyelids may also become red and puffy. If your cat rubs her eyes she can damage her corneas (the clear outer surface of her eyes).
Continued dryness will result in a buildup of dark pigment on your cat’s corneas, which would lead to blindness. The crusts on her eyelids are loaded with bacteria. You need to start treatment ASAP. Gently soak the crusts off using a moist washcloth (no hydrogen peroxide please). Next apply artificial tears at least once every hour until you can get that kitty in to see her doctor.
Your veterinarian will do a Schirmer tear test to confirm the diagnosis of KCS. A fluoresceine dye test will also be important to rule out secondary damage to her corneas. The next order of business will be finding the underlying problem. For many cats it results from smoldering upper respiratory infections like herpes or chlamydia. Other predisposing causes include nerve injury, drug side effects and, in dogs, distemper virus. But despite our best diagnostic efforts we can’t find the smoking gun in every case.
Nowadays we have good treatments for dry miserable eyes. Prescription tacrolimus ointment applied morning and night usually stimulates improved tear production in cats. Cyclosporine A also works well for dogs. You could use artificial tears alone but it’ll be a lot of work; your kitty will need them every hour every day. I urge you to give her the best chance possible of pain-free vision for the rest of her life.