My Dog's Ears Smell: Signs of Ear Infection and What to Do

A healthy dog's ears should not smell unpleasant. When a distinctive odour develops, usually musty, yeasty, or putrid, it is almost always a sign of an ear infection. Ear infections in dogs are common, particularly in breeds with floppy or heavily feathered ears, and they require veterinary treatment. They do not resolve on their own.

Is This an Emergency?

Go to a vet immediately if your dog:

• Is tilting their head or walking in circles alongside the ear symptoms (possible middle or inner ear infection)
• Has a sudden onset of balance problems or falls to one side
• Is pawing at the ear with extreme distress
• Has visible swelling of the ear flap (possible aural haematoma)

Call your vet the same day if:

• There is a strong smell from one or both ears
• You can see discharge inside the ear canal: brown, yellow, or black
• Your dog is shaking their head repeatedly or holding one ear down
• Your dog winces when the ear is touched

Wait and monitor for a short time only if:

• There is a very faint smell and no other symptoms, but schedule an appointment soon regardless

What Causes Smelly Ears in Dogs?

Bacterial infection (otitis externa)

Bacterial infections of the outer ear canal are the most common cause of ear odour in dogs. The ear produces a yellow or brown discharge and is painful to the touch. Requires topical and sometimes oral antibiotic treatment.

Yeast infection

Malassezia yeast causes a distinctive musty or cheesy smell and dark, waxy brown discharge. It frequently coexists with bacterial infection and is very common in dogs with allergies.

Ear mites (Otodectes cynotis)

Ear mites produce a dark, crumbly, coffee-ground-like discharge and cause intense itching. More common in young dogs. Contagious between dogs and cats in the same household.

Foreign body

A grass seed, piece of plant, or other object trapped in the ear canal causes intense irritation, head shaking, and sometimes infection.

Underlying allergy

Allergic skin disease, both environmental and food-related, frequently manifests in the ears. Dogs with recurrent ear infections should be investigated for an underlying allergy, as treating only the infection without addressing the allergy leads to repeated relapses.

Polyp or growth

Occasionally a polyp or mass in the ear canal causes chronic infection and discharge. Your vet will check for this during the examination.

Which Breeds Are More Prone to Ear Infections?

• Cocker Spaniel, Basset Hound, Labrador Retriever: Long, floppy ears reduce airflow, creating a warm, moist environment that favours infection
• Poodle, Bichon Frise: Hair inside the ear canal can trap moisture and debris
• German Shepherd, French Bulldog: Allergic skin disease frequently manifests in the ears
• Shar-Pei: Narrow ear canals increase infection risk

What Will the Vet Do?

Your vet will examine the ear canal with an otoscope to assess the type of discharge, the condition of the eardrum, and the presence of mites or foreign objects. They may:

• Take a swab for cytology (microscopic examination) to identify whether bacteria, yeast, or mites are present
• Prescribe medicated ear drops: antibacterial, antifungal, or antiparasitic depending on the cause
• Flush the ear canal under sedation for severe or chronic cases
• Recommend allergy investigation if infections are recurrent

How to Help Your Dog at Home

• Do not attempt to clean deep inside the ear yourself, as this can push debris further in and damage the eardrum
• Use only vet-recommended ear cleaning solution, applied to the outer ear canal
• After swimming or bathing, gently dry the ear flap and outer canal
• Keep ear hair trimmed if your vet recommends it, but do not over-pluck, as this can cause inflammation
• Never use cotton buds inside the ear canal
• Complete the full course of any prescribed ear drops, even if the ear appears to have improved