Dog Ear Infection: Symptoms, Causes, Treatment, and When to See a Vet

A dog ear infection is a clinical problem, not just “dirty ears.” Inflammation of the ear canal (otitis externa) is common, and deeper middle or inner ear disease can also occur. Dogs shake their heads, scratch, smell “off,” or produce discharge for several reasons — yeast, bacteria, allergies, moisture, foreign material, polyps, or other underlying drivers. What you do next depends mainly on pain level, neurological signs, how fast it started, and whether the ear canal is severely swollen or ulcerated.

This article is educational and does not replace a hands-on veterinary examination. If your dog has a head tilt, loss of balance, facial droop, severe pain, or a sudden inability to open the mouth comfortably, contact a veterinarian promptly — see the warning signs section below.

What Do Dog Ear Infection Symptoms Look Like?

Owners usually notice behaviour before they see the canal clearly:

• Head shaking or head tilting toward one side
• Scratching or rubbing the ear on the floor or furniture
• Redness inside the ear flap or canal opening
• Discharge — brown, yellow, or waxy material
• Strong or yeasty odour from the ear
• Pain when the ear base is touched
• Swelling that narrows the canal opening
• Hair loss or crusting around the ear
• Hearing seeming reduced on one side
• Balance problems, circling, or eye flickering if deeper structures are involved
• Recurring “dirty ears” despite regular cleaning
• Puppy ear infection signs after swimming or a bath

Smell and head shaking are two of the most common owner searches for a reason — they are often the first obvious clues.

Why Do Dogs Get Ear Infections?

Ear infections rarely appear from nowhere. Common contributors include:

• Allergies — a major driver of recurrent otitis in many dogs
• Moisture — swimming, humid weather, incomplete drying after baths
• Yeast overgrowth — especially in warm, moist canals
• Bacterial infection — sometimes secondary to inflammation or trapped debris
• Ear shape and hair — floppy ears and dense canal hair can reduce airflow
• Foreign material — grass awns and debris in outdoor dogs
• Endocrine or skin disease — can change the ear environment
• Polyps, masses, or chronic changes — more often in long-running cases

In consults, owners often ask for “ear drops that always work.” The more useful question is what is driving the inflammation — infection type and underlying cause both matter.

Outer vs Middle vs Inner Ear

Most everyday “dog ear infection” searches describe outer ear disease. Neurological signs should never be treated as a simple dirty-ear problem.

Mild Irritation vs True Infection

Mild redness after swimming

May settle with proper drying and veterinary-approved cleaning — but if odour, pain, or discharge develops, book an exam rather than waiting through another week of head shaking.

Recurring infections

Almost always mean an underlying driver (often allergy) is still active. Cleaning alone will not fix the pattern long term.

Severe swelling or closed canal

Needs professional care. Forcing home drops into a painful, swollen canal can make things worse.

When Are Dog Ear Problems Urgent?

What Will a Veterinarian Check?

History. Swimming, allergies, previous ear infections, cleaning products used, and how long signs have been present.

Physical examination. Ear flap, canal opening, pain response, lymph nodes, and skin elsewhere (allergy clues).

Otoscopy. Looking down the canal when the dog can tolerate it — sometimes after pain control.

Cytology. A microscope check of discharge to see yeast, bacteria, and inflammatory cells — this often guides treatment better than guessing.

Culture in selected resistant or severe cases.

Further tests for recurrent disease — allergy work-up, endocrine screening, or imaging when middle-ear disease is suspected.

Treating a Dog Ear Infection

Effective treatment usually combines:

• Cleaning under guidance when safe — debris blocks medication
• Topical medication matched to what is found on cytology (yeast, bacteria, or both)
• Pain and inflammation control as prescribed
• Addressing the underlying cause — especially allergies in repeat cases
• Follow-up checks so treatment is not stopped too early

Over-the-counter drops from a random shelf can be the wrong drug for the wrong organism, or too harsh for an ulcerated canal. Human ear medications are not automatically safe for dogs.

This article does not list product names or doses. Those decisions need examination and, ideally, cytology.

What You Can Do at Home While You Arrange Care

• Prevent swimming until the ear is assessed
• Do not dig cotton buds deep into the canal
• Avoid alcohol or harsh home remedies in a painful ear
• Note the smell and colour of discharge
• Take a clear photo of the ear opening in good light
• Use an Elizabethan collar if scratching is causing trauma
• Keep other household dogs from sharing bedding if discharge is heavy (hygiene, not a guarantee against all causes)
• Bring previous ear-medication names to the appointment

Can Dog Ear Infections Improve?

Yes — many outer ear infections improve when the right medication is used for long enough and the canal is cleaned appropriately. Recurrence is common if allergies or moisture drivers are not managed. Middle and inner ear disease can take longer and may need a more intensive plan. Chronic untreated infection can lead to canal scarring and long-term discomfort.

Questions to Track Before the Veterinary Appointment

• One ear or both?
• When did head shaking or odour start?
• Any swimming or recent bath?
• Colour and smell of discharge?
• Is the dog in obvious pain when you touch the ear base?
• Any head tilt or balance change?
• History of allergies or repeated ear infections?
• What cleaners or drops have you already used?
• Any other itchy skin areas (paws, belly, armpits)?
• Puppy or adult? Breed with heavy ear flaps?

Frequently Asked Questions

How do I know if my dog has an ear infection?
Common clues are head shaking, scratching, odour, redness, and discharge. Only an exam (often with cytology) confirms infection type.

What does an ear infection look like in a dog?
Red canal opening, wax or pus-like discharge, swelling, and sometimes a brown or yellow crust. Deeper disease may add head tilt.

What should I do for a dog ear infection?
Book a veterinary exam rather than starting random drops. Keep the dog from swimming and stop deep digging in the canal.

Are dog ear infections contagious to humans or other pets?
Most are not primarily “catching” like a cold, but shared underlying environments (and some organisms) mean hygiene still matters. Ask your vet about your specific household.

Can I treat a dog ear infection at home?
Home cleaning may support care after a diagnosis. Untargeted home treatment of a painful, swollen ear often delays proper care.

Why does my dog keep getting ear infections?
Recurrence usually means an underlying driver — frequently allergy, moisture, or incomplete prior treatment — is still present.

What about inner ear infection in dogs?
Inner/middle ear involvement can cause balance signs and needs prompt veterinary assessment, not only outer-ear drops.

When should I see a vet for a dog ear infection?
As soon as signs appear if the dog is painful; urgently if there is head tilt, severe swelling, or rapid worsening.

Conclusion

Dog ear infections are extremely common and highly searchable for a reason — head shaking, odour, and discharge are hard to ignore. Because yeast, bacteria, allergies, and deeper ear disease need different approaches, the strongest plan is veterinary assessment with appropriate canal evaluation and cytology rather than repeating the same over-the-counter drop. Seek urgent care for neurological signs, severe pain, or rapidly closing canals. With the right diagnosis and a full treatment course, many dogs become comfortable again — and recurrence drops when the underlying trigger is also addressed.

Medical disclaimer: This article is intended for general education and does not constitute veterinary advice, diagnosis, or treatment. Every dog is different, and only a licensed veterinarian who has examined your dog can determine the cause of their symptoms and recommend appropriate care. If your dog is showing signs of a medical emergency, contact a veterinarian or emergency animal hospital immediately.