A pet owner strokes their white cat's chin.

What to Do with a Cat Ear Infection

Cat ear infections are common and can involve the outer ear or the inner ear. They can be caused by ear mites, bacteria, and/or yeast organisms. We will review common causes of cat ear problems and help you understand what you can do if you believe your cat has an ear infection.

Most Common Cat Ear Problems

Cats can get different ear problems and the symptoms can be similar, making it hard for the cat owner to know for sure the underlying problem. By far the most common problem of the cat ear is an infection in the exterior canal due to an ear mite infection. However, cats can have other types of infections and diseases.

Below we will review different types of cat ear problems.

Outer ear infection, also known as otitis externa, is an infection in the outer ear canal. The most common cause is ear mites that are very contagious and common in outdoor cats, strays and feral cats and may affect up to 90 percent of all cats at some point in their life. Ear mites are small parasites that live in the ear canal of cats. As they move around and feed on tissue in the ear canal they become extremely itchy and irritating to cats. Cats can also get bacterial and yeast infections in the ear.

Inner ear infections, also known as otitis interna or otitis media, are infections deeper in the ear canal. Signs of inner ear infections in cats are more serious and can include neurological signs such as a head tilt, abnormal pupil sizes, and balance abnormalities.

Nasopharyngeal polyps are abnormal growths of tissue that can occur anywhere in the ear, near the eardrum, nose, or the back of the throat of cats. The cause of polyp growth is unknown. Signs of problems will depend on the location of the polyp but when it involves the ear it can include recurrent infections, head tilt, balance problems, head shaking and sometimes abnormal pupil sizes.

Skin infections can occur around the ear. This is especially common in cats that scratch at their ears and damage the skin around the ear.

Trauma can occur around the ear causing an infection in the skin around the outer ear. Bite wounds are a common cause of trauma that can abscess causing pain and swelling around and even in the ear depending on the location of the bite.

Symptoms of Cat Ear Infections

Symptoms of a cat ear infection may include:

Head shaking
Scratching at the ears
Discharge in the ears
Balance problems
Abnormal pupil sizes
Odor coming from the ear
Skin lesions and hair loss around or on the ears from scratching

What to Do If Your Cat Has an Ear Infection

If your cat is showing symptoms of an ear infection, the best thing to do is to see your veterinarian.

When you go to your vet you can likely expect the following:

Your veterinarian will obtain a complete medical history and perform a physical examination including examination of the ears and inner ears using an instrument called an otoscope. They will also examine your cat for other signs of parasites such as fleas.
The following tests can help determine the cause of a cat’s ear-related symptoms:

Cytology is a test where the contents of the ear are examined on a glass slide using a microscope. Oil may be used to smear the discharge around to look for ear mites. The ear discharge may also be rolled onto a glass slide that is dried and stained to evaluate for other types of infections such as bacteria and/or yeast organisms.

Examination under sedation. Some ear infections are incredibly painful. Sedation may be required for evaluation and cleaning and also for a thorough evaluation of the ear, nose, mouth, soft palate to evaluate for a nasopharyngeal polyp.

Bacterial culture and sensitivity of the ear discharge may be performed to identify the offending organism to help direct therapy.

Radiographs or advanced diagnostics such as computerized tomography (CT or “cat” scan) may be required to identify polyps.

Treatment of a Cat Ear Infection

A cat ear infection is commonly treated with an ear cleaning followed by medications to treat the underlying problem. Medications that kill ear mites will be used for ear mite infections while anti-bacterial and anti-yeast medications will be used to treat bacterial or yeast infections.

Ear treatments may include:

Cleaning the ear. Depending on the medication used and the quantity of ear discharge, cleaning may be needed. Moderate to severe infections may require sedation and in-hospital flushing. There are several types of ear cleaners that can clear the wax or have antimicrobial properties.
Ear mite treatment. Topical therapy may consist of applying medication in the ear during the veterinary visit. Commonly used drugs include milbemycin (Milbemite®) or ivermectin (Acarexx®). Thiabendazole (Tresaderm®) may be prescribed for use at home. Selamectin (Revolution®) can also be applied topically between the shoulder blades at home or in the hospital.
Bacterial and yeast treatments. Treatment options include placing ear drops in your cat’s ears once or twice daily or newer medications may allow for a one-time treatment while at the vet’s office. Ear medications commonly include anti-inflammatory medications such as a steroid to reduce swelling and pain.
Systemic therapy with steroids may be used to decrease pain and inflammation.
Oral or injectable antibiotic therapy in cases of severe bacterial infection or ulceration. Results of sensitivity testing can be used to choose the appropriate antibiotic.
Antifungal therapy in cases of severe or recurrent yeast infections

For tips on applying ear medication, go to How to Administer Ear Medication to Your Cat.

What to Do with a Cat Ear Infection

Most Common Cat Ear Problems

Symptoms of Cat Ear Infections

What to Do If Your Cat Has an Ear Infection

Treatment of a Cat Ear Infection

Additional Articles on Cat Ear Infections