Otitis Externa (Ear Infections)
Learn what the condition is, how it may be detected early, how it is treated or managed, and which breeds or species are linked to it.
Condition snapshot
A concise guide to the condition’s pattern, detection, management and urgency.
This snapshot is a general guide, not a diagnosis or treatment plan. New, severe or worsening signs require veterinary assessment.
About the condition
Otitis externa is inflammation of the external ear canal. It is one of the most common reasons dogs develop painful, itchy ears. Ear shape can increase risk: long, pendulous or heavily haired ears reduce ventilation and retain moisture, but conformation alone is rarely the whole explanation. Allergic skin disease, parasites, foreign bodies, excessive moisture and endocrine disease can all initiate inflammation, while bacteria and yeast commonly multiply secondarily in the altered ear environment.
Early signs include head shaking, scratching, redness, increased wax, odour or sensitivity when the ear is touched. Discharge can be brown, yellow or creamy depending on the organisms and degree of inflammation. Chronic disease causes the canal lining to thicken and the opening to narrow. Mineralisation and scar tissue can eventually make the canal rigid and permanently obstructed.
Untreated external-ear infection can extend through a damaged eardrum into the middle ear. Dogs may then develop deeper pain, hearing loss, head tilt or balance abnormalities. Repeated treatment without identifying the underlying cause is a common reason infections keep returning.
Allergy investigation is often necessary when both ears repeatedly flare.
Otitis externa is therefore not simply “dirty ears.” Cleaning may help prevention in selected dogs, but a painful infected canal needs diagnosis and targeted therapy. Long-term control depends on correcting the primary trigger as well as treating the organisms that flourish after inflammation begins.
Repeated ear inflammation should therefore be viewed as a condition with an underlying cause, not simply a series of unrelated infections. Identifying the factor that keeps the ear canal inflamed is central to preventing the cycle of swelling, microbial overgrowth and progressively narrowed ear canals.
Look and smell without inserting objects into the canal. A sudden one-sided infection can indicate a grass seed or other foreign body, while repeated bilateral disease commonly accompanies allergy. Ear mites are more common in some younger or exposed dogs.
Screening & Early Detection
Otitis externa is best prevented and detected through assessment of ear health and underlying risk factors rather than a predictive laboratory test. Early detection is based on regular inspection, especially in dogs with pendulous ears, a history of allergy, frequent swimming or previous infections. New redness, odour, wax, head shaking or scratching warrants closer assessment.
Routine veterinary examinations should include inspection of the ear openings and, where practical, otoscopy. Dogs with recurrent disease may benefit from scheduled checks before obvious pain develops. Cytology is the key test once inflammation is present because it identifies yeast and bacterial populations that cannot be determined accurately from the colour of discharge alone.
The veterinarian should also search for primary causes. Chronic narrowing may prevent adequate visualisation of the eardrum and require sedation.
Seek prompt care if the dog cries when the ear is touched, develops a head tilt, loses balance or becomes unusually lethargic, as middle-ear involvement may be present. Preventive screening is therefore regular observation and targeted veterinary examination, not routine antibiotic drops or aggressive cleaning of a normal ear.
Diagnosis includes otoscopic examination of the canal and eardrum when visible. Cytology of ear debris shows whether bacteria, yeast or inflammatory cells are present and helps select treatment. Culture is useful in resistant or recurrent bacterial infections.
Treatment & Management
Treatment begins with identifying what is present in the ear and why inflammation developed. Cytology guides the choice of topical medication, which may contain an antifungal, antibiotic, anti-inflammatory or a combination. The canal is cleaned enough to remove debris so medication can contact the skin, but cleaning a severely painful or ulcerated ear may require sedation.
The eardrum should be assessed before using products that could damage the middle ear. Do not apply vinegar, peroxide, alcohol or leftover ear medication without veterinary advice because inflamed tissue can be worsened and some drugs are unsafe if the eardrum is ruptured.
Recurrent otitis will not remain controlled unless the underlying trigger is addressed. Dogs with allergic skin disease may need long-term allergy management. Foreign bodies are removed, parasites treated and endocrine disorders investigated when indicated. Preventive cleaning can be useful for selected dogs that swim or produce heavy wax, but frequency should be individualised.
Chronic end-stage ear canals can become so narrowed and painful that topical treatment no longer reaches the diseased tissue. In those cases, surgery to remove the affected ear canal may provide the best long-term relief.
Follow-up cytology is important because ears can look better before infection is fully controlled. The goal is not simply to stop odour for a few days but to return the canal to a comfortable state and reduce the conditions that cause repeated relapse.
Breeds or species affected
Airedale Terrier
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Basset hound
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Beagle
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Bloodhound
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British Bulldog
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Cavalier king charles spaniel
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Shar Pei
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Chow chow
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Cocker spaniel
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English springer spaniel
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German shepherd
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Golden retriever
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Labrador retriever
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Miniature Poodle
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Miniature Schnauzer
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Toy Poodle
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Schnauzer (miniature, standard)
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Springer spaniel
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