Ear Infections in Cats: Causes, Treatment, and Prevention

Cats don't often get ear infections, but when they do, the cause can be complex.

If your vet has ruled out mites -- the culprit in about half of all feline ear infections -- she'll have to do some sleuthing to figure out what's causing your cat's outer or middle ear infection. It could be allergies, or an underlying illness like diabetes, tumors, a damaged eardrum, or feline leukemia virus.

Diagnosing the condition may require sedation or X-rays, but treating ear infections usually isn't complicated. Antibiotics, antiparasitics, and corticosteroids are the most common treatments.

What's essential is that you get your cat in for treatment as soon as you notice signs of ear discomfort. Ear infections can become chronic and lead to deafness and facial paralysis.

What Causes Ear Infections in Cats?

Generally, unless your cat has picked up mites from another animal, ear infections are a secondary condition. That means they are actually the result of some other underlying medical problem.

Here are some of the contributing causes and perpetuating factors for external ear infections, called otitis externa, and middle ear infections, called otitis media:

  • an overgrowth of yeast or bacteria – often both
  • wax buildup in the ear canal
  • thick hair in the ear canal
  • hypothyroidism
  • autoimmune diseases
  • foreign bodies like tumors or the bristle from grass
  • environmental irritants
  • diabetes mellitus

Infections of the middle ear are usually the result of an infection that has spread there from the outer ear canal. Tumors, a ruptured ear drum, or improper ear cleaning can also lead to middle-ear infections in cats.

What Are the Signs of an Ear Infection in a Cat?

A cat will show his discomfort by scratching or pawing at his ear or shaking or tilting his head in the direction of the painful ear. Other symptoms to look for include:

  • black or yellowish discharge
  • redness or swelling of the ear flap or ear canal
  • waxy buildup on or near the ear canal
  • discharge from the ear that resembles coffee grounds and signals ear mites
  • strong odor
  • hearing loss
  • loss of balance or disorientation