Dog Ear Infections: Signs, Cost, and Prevention

Health guide · By Hollis Barrow · Published September 21, 2026 · Updated September 22, 2026

Written for general planning, not medical advice — no one at Argos Paws is a veterinarian. If something is wrong with your dog right now, call your vet or the nearest emergency clinic.

Ear infections (otitis externa) are one of the most common reasons for a vet visit, and one of the most preventable with a few consistent habits — especially once you understand what's actually causing them, not just which breeds are prone.

Signs to watch for

• Head shaking or tilting.
• Scratching at one or both ears more than usual.
• A noticeable odor from the ear.
• Redness, swelling, or dark discharge inside the ear.
• Sensitivity or pain when the ear area is touched.

What's actually causing it

The Merck Veterinary Manual — the standard veterinary reference, authored on this topic by a board-certified veterinary dermatologist — draws a distinction worth understanding: a primary cause alters the ear's environment in an otherwise normal ear, most often allergy (food, environmental, or contact), but also parasites, endocrine disease, or foreign bodies. That altered environment then allows a secondary cause — bacterial or yeast infection, most commonly Malassezia — to actually take hold. Overcleaning is also listed as a secondary cause in its own right.

This matters practically: treating the current infection without addressing the primary cause behind it just resets the clock. The manual is explicit that the inciting cause must be addressed to prevent recurrence — which is exactly why a dog with repeated ear infections despite repeated treatment usually has an underlying allergy that hasn't been managed yet, not "bad luck" with infections.

Which dogs are most prone, and why

These map directly onto what veterinary reference sources classify as predisposing factors — traits that don't cause an infection on their own but make the ear more vulnerable when a primary cause is present.

What treatment costs

The surgical end of that range is rare and reserved for chronic cases that haven't responded to repeated medical treatment — most single infections resolve well within the standard treatment range. Worth noting: an untreated outer-ear infection (otitis externa) can progress into the middle ear (otitis media) or, less commonly, the inner ear (otitis interna), both more serious and more expensive to treat than catching it early. Prompt treatment at the first signs is the cheaper and less painful path.

Prevention habits that actually help

• Dry ears thoroughly after swimming or baths — a simple towel dry, or a vet-recommended drying solution for water-loving breeds.
• Routine ear checks — a quick weekly look and sniff catches problems before they become painful or expensive.
• Regular ear hair trimming for breeds prone to excess hair in the canal — ask your groomer to include this.
• Address allergies directly — treating the underlying allergy (not just the ear symptom) is what actually breaks a recurring cycle, since allergy is the most common primary cause behind repeat infections.
• Don't over-clean — the Merck Veterinary Manual lists overcleaning as its own secondary cause of otitis externa; it can disrupt the ear's natural cleaning mechanism and cause irritation. Follow your vet's recommended frequency rather than cleaning preemptively too often.

Written by Hollis Barrow

Hollis writes Argos Paws, drawing on years of large-breed dog ownership (Labrador, German Shepherd). Every figure here is compiled from published industry and veterinary sources, checked against the original, and cited.

More about Argos Paws →

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Frequently asked questions

What's actually causing my dog's ear infection — is it just moisture?

Moisture and ear shape are risk factors, but the Merck Veterinary Manual draws a sharper distinction: a primary cause (most often allergy — food, environmental, or contact) alters the ear's environment, which then allows a secondary infection (bacteria or yeast, most commonly Malassezia) to take hold. Ear conformation and moisture are predisposing factors that make the ear more vulnerable, but they're rarely the whole story on their own — which is why an ear infection that keeps returning despite repeated treatment often points to an unaddressed allergy underneath it.

Why do ear infections keep coming back even after treatment?

Because treating the infection without addressing what caused it just resets the clock. The Merck Veterinary Manual is explicit that the inciting cause must be addressed to prevent recurrence — if allergies are driving repeated infections, clearing the current bacterial or yeast overgrowth without managing the allergy means the ear environment that allowed it in the first place is still there.

What happens if an ear infection is left untreated?

It can progress beyond the outer ear canal (otitis externa) into the middle ear (otitis media) or, less commonly, the inner ear (otitis interna) — both more serious and more expensive to treat than catching it early. Prompt treatment at the first signs is meaningfully cheaper and less painful for your dog than waiting to see if it resolves on its own.

Is over-cleaning my dog's ears actually bad?

Yes — the Merck Veterinary Manual specifically lists overcleaning as one of the secondary causes of otitis externa, alongside bacterial and yeast infection. Ear cleaning has a purpose (removing debris and excess moisture), but doing it more often than your vet recommends can disrupt the ear canal's natural cleaning mechanism and irritate the skin, working against you rather than for you.

How much does ear infection treatment typically cost?

Standard treatment (exam, cleaning, medication) commonly runs $100-250; more complicated or recurring cases can range $130-650. The rare surgical option for chronic, treatment-resistant cases (total ear canal ablation, or TECA) runs $3,000-4,200+, but that's reserved for cases that haven't responded to repeated medical management — most single infections resolve well within the standard range.

Which breeds are most at risk, and why?

Breed risk comes down to ear conformation and coat, which the Merck Veterinary Manual lists as predisposing factors: pendulous (floppy) pinnae and hairy or stenotic canals reduce airflow and trap moisture and debris. That's why Cocker Spaniels, Basset Hounds, and Beagles (floppy ears), Poodles and Schnauzers (excess canal hair), and frequent swimmers like Retrievers all show up disproportionately — the underlying mechanism is the same even though the specific trait differs.