Cat Ear Infections: Signs, Causes and How Vets Treat Them

By Tailwisp Editorial TeamUpdated October 20, 20264 min read

A healthy cat's ears are clean, pale pink and nearly odor-free. When something is wrong, the signs are hard to miss. An ear infection is painful, and without treatment, can damage hearing and balance.

What is an ear infection?

Otitis is inflammation of the ear. In cats, the infection is usually bacterial or yeast, but these organisms usually take hold only when something else has disturbed the ear. Otitis externa affects the outer ear canal. If the eardrum is damaged, the infection can spread to the middle ear, called otitis media, and inner ear, otitis interna.

Causes

• Ear mites, the most common cause in young cats. See ear mites in cats.
• Allergies, to food or the environment. See cat skin allergies.
• Polyps or tumors in the ear canal.
• Foreign bodies, such as grass seeds.
• Excess wax and moisture.
• Over-cleaning, or using irritating products.
• Immune problems, such as FIV or FeLV. See FeLV and FIV in cats.
• Narrow or abnormal canals, such as in Scottish Folds.
• Trauma, from scratching.
• Skin disease, such as ringworm. See ringworm in cats.

Signs

• Head shaking and scratching.
• Redness inside the ear.
• Dark, yellow or green discharge.
• A bad smell.
• Wax buildup.
• Pain, or flinching when touched.
• Hair loss and scabs around the ear.
• Head tilt, circling, loss of balance or abnormal eye movements, if the inner ear is involved.
• Hearing loss.

Diagnosis

The vet looks in the ear with an otoscope, checks the eardrum and takes a swab, to examine under a microscope. Samples can show bacteria, yeast or mites. Further tests may include allergy workups, imaging or sedation for deep cleaning. See cat wellness exam: what to expect.

Treatment

• Ear cleaning, by the vet, sometimes under sedation.
• Medicated drops, containing antibiotics, antifungals or anti-inflammatories, depending on the findings.
• Oral medication, for severe cases or middle ear infection.
• Treatment of the cause, such as mites, allergies or polyps. Polyps may need surgery.
• Recheck visits, to make sure the infection has resolved.

Use only products prescribed by your vet. Some ear cleaners and drops are unsafe if the eardrum is ruptured.

Cleaning at home

Do not clean an inflamed or painful ear without advice. For routine care of healthy ears, see how to clean a cat's ears. Never use cotton swabs deep in the ear, which can push debris in or damage the eardrum.

Giving ear drops

Warm the bottle in your hand, hold the cat gently, lift the ear flap, and apply the number of drops advised. Massage the base of the ear for a few seconds, then let the cat shake. Wipe away excess. Use a towel wrap for fidgety cats. See how to give cat eye drops for similar technique, and reward afterwards.

Prevention

• Check ears weekly.
• Keep parasite prevention up to date.
• Manage allergies.
• Do not over-clean.
• Dry ears after a bath. See how to bathe a cat.

Outlook

Most infections respond well to treatment. Chronic or repeated infections suggest an underlying cause that needs to be found.

Chronic and recurring ear problems

If your cat keeps getting ear infections, the vet will look for an underlying cause. Allergies are a leading reason, so a food trial or environmental allergy testing may be suggested. Polyps and tumors in the canal can block drainage. A narrow canal or excess wax, particularly in certain breeds, can be involved. In stubborn cases, a CT scan or video otoscopy under anesthesia reveals middle ear disease. Sometimes surgery is required to remove polyps or open the canal.

Signs of middle or inner ear disease

Head tilt, wobbling, circling, rapid side-to-side eye movement and a drooping eyelid on one side suggest deeper problems. These need prompt veterinary care, since they can result in permanent damage. Horner's syndrome, which causes a droopy eyelid, small pupil and a raised third eyelid, can accompany middle ear disease.

Hearing

Cats with long-term ear disease may lose hearing. See caring for a deaf cat if it happens. Early treatment reduces the risk.

Questions to ask your vet

Ask what organisms were found, whether the eardrum is intact, how long to treat and how to apply drops. Ask what to do if the cat will not tolerate drops, since there are longer-acting options. Ask whether allergy testing makes sense if infections return, and when to schedule a recheck. Write the answers down so that you can follow the plan at home.

When to see a vet

See a vet if you notice odor, discharge, head shaking or a head tilt. Use the US vet directory to find a clinic.

This article is general educational information, not veterinary advice. Every cat is different. If your cat is unwell, or you are unsure about a symptom, diet change or medication, contact your veterinarian.