| BLOG OVERVIEW & KEY TAKEAWAYS Key Takeaway 1: Ear infections in dogs are caused by bacteria, yeast, or ear mites, and the treatment is completely different for each. A vet diagnosis before starting any treatment is essential. Key Takeaway 2: Dogs with floppy ears, dogs who swim regularly, and dogs with allergies are the highest-risk groups for recurring ear infections. Managing the root cause is how you stop the cycle. Key Takeaway 3: Do not use cotton swabs inside your dog’s ear canal, do not pour hydrogen peroxide inside the ear, and do not skip completing the full course of prescribed medication even when symptoms improve. |
Something Is Wrong With Your Dog’s Ears
They are shaking their head constantly. Scratching at the same ear over and over. You lean in and there is a smell that should not be there. Or you notice dark brown discharge when you check inside.
Ear infections are one of the most common reasons dog owners end up at the vet. According to the American Kennel Club, they affect millions of dogs each year, and certain breeds deal with them on a near-chronic basis.
The good news is that most ear infections are very treatable when caught early. The key is knowing what you are dealing with, because the treatment for a bacterial infection is different from a yeast infection, which is different again from ear mites.
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Why Dog Ears Are Prone to Infection
A dog’s ear canal is shaped like an L. Sound travels down vertically, then bends horizontally toward the eardrum. That shape traps moisture, debris, and wax in a warm, dark environment that bacteria and yeast absolutely love.
Add floppy ears on top of that, which further restrict airflow, and you have a breeding ground for infections. This is why Cocker Spaniels, Basset Hounds, Labrador Retrievers, and Poodles are among the most frequently affected breeds.
The Three Types of Dog Ear Infections
Otitis Externa (Outer Ear)
By far the most common type. The infection affects the outer ear canal, the part you can see and partially reach. This is what most people mean when they say their dog has an ear infection.
Symptoms are usually obvious: scratching, odor, discharge, and redness at the ear opening.
Otitis Media (Middle Ear)
The infection has spread past the eardrum into the middle ear. This is more serious. It often develops when an outer ear infection goes untreated too long.
Signs include significant pain when the jaw moves, reluctance to chew, head tilt, and in some cases balance problems.
Otitis Interna (Inner Ear)
The deepest and most serious form. The infection has reached the inner ear structures. Dogs may lose their balance entirely, walk in circles, experience nystagmus (rapid involuntary eye movement), or show signs of hearing loss.
Both otitis media and interna require aggressive veterinary treatment. They cannot be managed at home.
What Is Causing the Infection? Common Culprits
Yeast Overgrowth
Malassezia yeast is the most common cause of dog ear infections. It thrives in warm, moist environments. You will usually notice a musty, sweet, or sour smell and dark brown or black waxy discharge.
Yeast ear infections are directly connected to skin allergies and systemic yeast overgrowth. If your dog has recurring yeast ear infections, allergies are almost certainly involved. You can read more about whole-body yeast infections in our detailed guide on the Shop With Pets blog.
Bacterial Infection
Bacterial ear infections tend to produce more yellow or greenish pus-like discharge with a sharper, more unpleasant odor than yeast. The ear may look more inflamed and feel warmer to the touch.
Bacteria and yeast often co-exist in the same infected ear, which is why veterinary testing before treating matters. Using an antifungal medication on a bacterial infection, or vice versa, will not work.
Ear Mites
Ear mites are tiny parasites that live inside the ear canal. They produce a characteristic dark, crumbly discharge that looks like coffee grounds.
Ear mites are more common in puppies and in dogs with outdoor exposure or contact with other animals. Unlike bacterial and yeast infections, ear mites are contagious to other pets in the household.
Allergies
Food allergies and environmental allergies are among the most common underlying causes of chronic, recurring ear infections. When the immune system is reacting to an allergen, it creates inflammation in the ear canal that changes the local environment enough to allow bacteria or yeast to overgrow.
If your dog has had three or more ear infections in a year, allergies are almost certainly involved. Treating only the infection without addressing the allergy guarantees recurrence.
Moisture and Foreign Objects
Water trapped in the ear canal after swimming or bathing is a significant infection trigger. Grass seeds, foxtails, and debris can also work their way into the ear canal and cause irritation that progresses to infection.
Symptoms: What to Look For
- Head shaking, especially if persistent or accompanied by ear scratching
- Scratching at one or both ears, sometimes causing skin breaks or rawness around the ear
- Brown, yellow, or black discharge from the ear canal
- Redness or swelling inside the ear flap or at the ear canal opening
- Strong, unpleasant odor from the ear
- Tilting the head consistently to one side
- Whimpering or pulling away when the ear is touched
- Crusting or scabbing around the outside of the ear
- Loss of balance or walking in circles, which indicates the infection has reached the middle or inner ear
How Vets Diagnose Ear Infections
Your vet will examine the ear with an otoscope to visualize the ear canal and assess the eardrum. They will take a swab of the discharge and examine it under a microscope to identify whether bacteria, yeast, or mites are present.
This step is not optional. The microscopy results determine the correct medication. Many ear infections involve both yeast and bacteria simultaneously, requiring a combination treatment product.
For chronic or recurring infections, your vet may recommend a culture to identify the specific organism and test which antibiotics it responds to. This is especially helpful when a dog has been treated multiple times and the infection keeps returning.
Treatment: What to Expect
Veterinary-Prescribed Ear Drops
The foundation of outer ear infection treatment is medicated ear drops prescribed by your vet. Most contain a combination of an antibiotic, an antifungal, and a steroid to address infection and inflammation simultaneously.
Application matters. Your dog’s ear canal is L-shaped. To get medication to the horizontal portion where infection lives, you need to fill the canal with the drops and then firmly massage the base of the ear from the outside for 30 to 60 seconds. You should hear a squelching sound. That means the medication has reached the lower canal.
Ear Cleaning
Your vet will likely clean the ear at the appointment and may send you home with an ear cleaning solution to use between treatments. Use a vet-recommended cleaner, not homemade remedies.
Fill the canal with the solution, massage the base, then let your dog shake their head, then wipe the visible parts of the ear with a cotton ball or gauze. Never use cotton swabs inside the ear canal. They push debris and bacteria deeper rather than removing it.
Oral Medications
Severe, deep, or chronic infections often require oral antibiotics or antifungals in addition to topical treatment. Dogs with middle or inner ear infections always require systemic medication.
Treating the Underlying Cause
This is the step that prevents recurrence. If allergies are driving repeated ear infections, managing the allergy, whether through diet change, medication like Apoquel or Cytopoint, or allergen immunotherapy, is the only long-term solution.
| IMPORTANT: Never use hydrogen peroxide, apple cider vinegar, or rubbing alcohol inside your dog’s ear. These can damage the ear canal lining, worsen inflammation, and cause significant pain. If the eardrum is ruptured, they can cause hearing damage. |
Home Care Between Vet Visits
- Keep the ear dry. No swimming until the infection is fully resolved and your vet clears it.
- Apply drops exactly as prescribed. Missing doses or stopping early allows the infection to return stronger.
- Use an Elizabethan collar if your dog is scratching aggressively. Self-inflicted trauma to an already infected ear significantly slows healing.
- Clean the outer ear gently with a cotton ball if discharge is visible. Do not probe the ear canal.
- Book the recommended follow-up appointment. Most ear infections require a recheck to confirm resolution.
Frequently Asked Questions
Q: Can a dog ear infection go away on its own?
Occasionally very mild irritation resolves without treatment. True infections caused by bacteria, yeast, or mites almost always worsen without treatment. Untreated ear infections can spread to the middle and inner ear, cause permanent hearing loss, and in extreme cases require surgical intervention. Do not wait it out.
Q: My dog keeps getting ear infections. What should I do?
Recurring infections nearly always have an underlying cause, usually allergies. Ask your vet about allergy testing or a dietary elimination trial. Once the underlying trigger is managed, infection frequency typically drops dramatically.
Q: Are ear infections contagious between dogs?
Bacterial and yeast infections are not typically contagious from one dog to another. Ear mites are highly contagious and require treatment of all pets in the household simultaneously.
Q: How long does it take for a dog ear infection to clear?
Most uncomplicated outer ear infections resolve in two to three weeks with appropriate treatment. Chronic or deep infections can take four to six weeks or longer. Always complete the full medication course and attend the follow-up appointment even if the ear looks and smells better early.
Q: Can I prevent ear infections in my dog?
For many dogs, yes. Check ears weekly for odor, redness, or abnormal discharge. Clean with a vet-approved solution on the schedule your vet recommends, typically monthly or after every swim. Dry ears thoroughly after baths or swimming. Manage any known allergies proactively.
When to Go to the Vet Today, Not Tomorrow
- Your dog is in obvious pain when the ear is touched
- You see bloody or pus-heavy discharge
- Your dog is losing balance, walking in circles, or showing eye movement abnormalities
- The ear canal looks swollen shut
- Symptoms have not improved after two to three days on prescribed treatment
Final Thought
Ear infections are uncomfortable and can escalate quickly when left alone. But they are also very manageable when caught early and treated correctly.
Check your dog’s ears weekly. Know what normal looks and smells like for your dog. Act when something changes.
That two-minute weekly check has prevented more ear infections than any medication.
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| DISCLAIMER The content in this article is for general informational and educational purposes only. It is not veterinary medical advice. Always consult a licensed veterinarian before making any decisions about your dog’s health, medication, or care routine. Shop With Pets and its owners are not liable for any damages, losses, or adverse outcomes resulting from use of or reliance on information published on this site. Every dog is different. What works for one may not be appropriate for another. In a pet health emergency, contact your veterinarian immediately. |
Sources:
- American Kennel Club, Dog Ear Infections: Symptoms, Causes, Treatment (2025)
- GoodRx, Ear Infection in Dogs: Symptoms and Treatment (2025)
- Merck Veterinary Manual, Otitis Externa in Dogs
- Cornell University College of Veterinary Medicine, Ear Cleaning Guidelines