Ear Infections (Otitis Externa)

What is it?

Otitis externa is inflammation of the outer ear canal. Dogs' L-shaped canals trap moisture and debris, letting yeast and bacteria overgrow. Allergies are the most common underlying trigger, followed by swimming, ear mites, foreign material like grass awns, and ear shape.

What signs should I watch for?

Signs to watch for include head shaking or scratching at the ears, odor or brown/yellow discharge, redness or swelling of the canal, pain when the ears are touched, and head tilt or loss of balance in severe cases.

How is it diagnosed and treated?

Your veterinarian looks into the canal with an otoscope and examines a sample of debris under the microscope to identify yeast, bacteria, or mites. Treatment usually includes a thorough ear cleaning and medicated ear products; stubborn cases may need a culture or sedated flushing.

Can it be prevented, and what's the outlook?

• Finishing every dose and returning for a recheck matters, because partly treated infections tend to return.
• Controlling allergies and drying ears after swimming help prevent repeat episodes.