Why Does My Dog Keep Getting Ear Infections? Understanding the Underlying Cause
By Dr. Amelia Rauch, Owner and Veterinarian, Highview Veterinary Hospital
Ear infections are one of the most common reasons dogs visit me at Highview Veterinary Hospital. While an occasional ear infection can happen even in otherwise healthy dogs, recurring ear infections often signal an underlying medical problem that needs to be addressed.
One of the biggest mistakes I see is treating each infection as an isolated event. Although medication may temporarily clear up the infection, if we don't identify what's causing it in the first place, those painful ear infections are likely to return.
Let's take a closer look at why recurring ear infections happen, how I diagnose them, and what we can do to help prevent them from coming back.
What Is an Ear Infection?
To understand why ear infections can become chronic, it helps to understand the anatomy of a dog's ear.
Unlike human ears, a dog's ear canal is shaped like the letter "L." It consists of:
A vertical ear canal, which is the portion you can see when you lift the ear flap.
A horizontal ear canal, which extends deeper toward the eardrum and cannot be fully visualized without specialized equipment.
Because of this unique shape, moisture, wax, and debris can become trapped deep within the horizontal canal, creating the perfect environment for bacteria and yeast to thrive.
Dogs commonly develop:
Yeast ear infections
Bacterial ear infections
Mixed infections involving both yeast and bacteria
Signs Your Dog May Have an Ear Infection
Some of the most common symptoms I see include:
Frequent head shaking
Scratching at the ears
Red, swollen ears
Ears that feel warm to the touch
A foul or "yeasty" odor
Brown, black, or yellow discharge
Pain when the ears are touched
Crying or yelping while scratching
In more severe cases, dogs may develop:
Head tilt
Loss of balance
Difficulty walking normally
These advanced signs may indicate that the infection has spread deeper into the ear and requires prompt veterinary attention.
Why Does My Dog Keep Getting Ear Infections?
When a dog experiences repeated ear infections, my goal shifts from simply treating the infection to identifying the underlying cause.
Allergies: The Most Common Cause
By far, the most common cause of recurring ear infections I see in dogs throughout Boerne and South Texas is allergies.
Environmental Allergies
Many dogs develop allergies to:
Grass pollens
Tree pollens
Weeds
Dust mites
Mold
Because these allergens fluctuate with the seasons, some dogs experience ear infections primarily during the spring and fall.
The inflammation caused by allergies changes the environment inside the ear canal, trapping moisture and debris and allowing yeast and bacteria to multiply.
Food Allergies
Food allergies are another common culprit.
One phrase I often use when discussing food allergies with owners is that they commonly affect "the ears, the rears, and the feet."
Dogs with food allergies often experience:
Recurring ear infections
Excessive paw licking
Itchy skin
Scooting
Anal gland irritation
One clue that raises my suspicion for a food allergy is when ear infections occur year-round rather than seasonally.
Moisture Can Lead to Chronic Ear Infections
Moisture is another major contributor.
Dogs that frequently:
Swim
Get bathed often
Spend time in humid environments
are at greater risk of developing ear infections.
Yeast thrives in warm, dark, moist environments, making a wet ear canal the perfect place for it to grow.
Keeping ears dry after swimming or bathing can go a long way toward preventing infections.
Some Dog Breeds Are More Prone to Ear Infections
Certain breeds are naturally predisposed because of their ear anatomy.
The breeds I most commonly see with recurring ear infections include:
Cocker Spaniels
Basset Hounds
Labrador Retrievers
Poodles
Goldendoodles and Labradoodles
French Bulldogs
Dogs with long, floppy ears or dense hair inside the ear canal often have reduced airflow, allowing moisture to become trapped more easily.
Are Ear Mites Causing My Dog's Ear Infection?
Many owners worry about ear mites, but in adult dogs they are actually quite uncommon.
Ear mites are much more frequently diagnosed in:
Puppies
Kittens
Cats
In adult dogs, recurring ear infections are far more likely to involve yeast, bacteria, allergies, or another underlying medical condition.
Foreign Material Can Trigger Ear Problems
Dogs that spend a lot of time outdoors may develop chronic irritation from foreign material trapped inside the ear canal.
Examples include:
Grass awns
Foxtails
Plant material
Dirt
Even a small foreign object can create ongoing inflammation that leads to repeated infections until it is removed.
Other Medical Conditions Can Contribute
Recurring ear infections aren't always caused by the ears themselves.
Certain medical conditions can increase a dog's susceptibility, including:
Hypothyroidism (low thyroid hormone)
Autoimmune diseases
Other immune system disorders
This is why I take a comprehensive approach when evaluating dogs with chronic ear disease rather than simply prescribing another ear medication.
How I Diagnose Chronic Ear Infections
Every diagnostic workup begins with a thorough physical examination.
Otoscopic Examination
Using an otoscope, I evaluate:
The vertical ear canal
The horizontal ear canal
The eardrum
This allows me to determine how severe the infection is and whether additional problems are present.
Ear Cytology
One of the most valuable diagnostic tools is ear cytology.
This involves gently collecting material from the ear canal and examining it under a microscope.
Ear cytology allows me to identify:
Yeast
Cocci-shaped bacteria
Rod-shaped bacteria
Inflammatory cells
Knowing exactly what organism is present helps me choose the most effective treatment.
Ear Culture
For dogs with severe or recurring infections, I may recommend an ear culture.
A laboratory can identify the specific bacteria involved and determine which antibiotics are most effective, particularly when resistant bacteria are suspected.
Why Over-the-Counter Treatments Often Fall Short
Many owners understandably try over-the-counter ear cleaners or remedies they find online before scheduling an appointment.
Unfortunately, these products rarely solve chronic ear infections.
In some cases, using the wrong medication can actually worsen the problem.
The key isn't simply cleaning the ears—it's identifying both the organism causing the infection and the underlying reason the infection developed in the first place.
Treatment Depends on the Underlying Cause
Treatment often includes:
Thorough ear cleaning
Prescription ear medications
Oral medications when appropriate
Allergy management
Addressing endocrine or immune disorders
Removing foreign material if present
Every treatment plan is tailored to the individual patient.
Can Ear Infections Cause Permanent Damage?
Unfortunately, yes.
Repeated inflammation causes scar tissue to develop inside the ear canal.
Over time, the canal becomes narrowed—a condition called stenosis—making it even easier for moisture and debris to become trapped.
Without proper treatment, chronic ear disease can lead to:
Chronic pain
Hearing loss
Ruptured eardrum
Permanent narrowing of the ear canal
Advanced surgery in severe cases
The sooner recurring infections are addressed, the better the long-term outcome.
How to Help Prevent Future Ear Infections
Although not every infection can be prevented, several steps can reduce your dog's risk:
Keep ears dry after swimming or bathing.
Follow your veterinarian's recommendations for ear cleaning.
Use only veterinarian-approved ear cleaners.
Manage allergies proactively.
Schedule follow-up examinations to ensure infections have completely resolved.
One of the most common reasons infections recur is that they never fully cleared in the first place. Recheck appointments help us confirm your dog's ears are truly healthy before stopping treatment.
Frequently Asked Questions
Why does my dog keep getting ear infections?
Recurring ear infections are commonly caused by allergies, trapped moisture, foreign material, or underlying medical conditions such as hypothyroidism.
Are recurring ear infections a sign of food allergies?
They certainly can be. Dogs with food allergies often experience recurring ear infections, especially if symptoms occur throughout the year.
Should I clean my dog's ears every week?
Some dogs benefit from routine ear cleaning, while others do not. The ideal cleaning schedule depends on your dog's breed, lifestyle, and underlying health conditions.
Can I use hydrogen peroxide or alcohol in my dog's ears?
No. Both hydrogen peroxide and rubbing alcohol can irritate the delicate lining of the ear canal and may worsen inflammation.
Are some breeds more prone to ear infections?
Yes. Cocker Spaniels, Basset Hounds, Labrador Retrievers, Poodles, Doodles, and French Bulldogs commonly experience ear problems because of their ear anatomy.
When should I schedule an appointment?
If your dog is shaking their head, scratching their ears, has a foul odor coming from the ears, develops ear discharge, or has experienced more than one ear infection within the past year, it's time for a veterinary evaluation.
Don't Just Treat the Infection—Find the Cause
Recurring ear infections are usually a symptom rather than the disease itself.
The key to long-term success is identifying and treating the underlying cause. Early intervention not only relieves discomfort but also helps prevent permanent damage, hearing loss, and chronic pain.
If your dog keeps getting ear infections, don't settle for treating the symptoms over and over again.
At Highview Veterinary Hospital, my team and I work to uncover the root cause of your dog's ear problems so we can create a treatment plan that provides lasting relief and improves your dog's quality of life. If your dog has recurring ear infections, we'd love to help.
