If your dog won't stop scratching their ears or shaking their head, there's a good chance a yeast infection is to blame.
Ear infections are one of the top three most common reasons dogs are brought to the vet, and yeast is one of the most common culprits behind them.
The good news is that yeast ear infections are very treatable, and with the right knowledge, many can be prevented entirely. But they can also be sneaky: recurring infections, that telltale musty smell, and chronic discomfort are all signs that something deeper may be going on.
This guide covers everything you need to know, from what causes yeast to overgrow in your dog's ears, to how to spot the signs early, treat them effectively, and stop them from coming back.
What Is a Dog Ear Yeast Infection?
A yeast infection in a dog’s ear is typically caused by an overgrowth of Malassezia pachydermatis, a type of yeast that normally lives on canine skin. In healthy dogs, this yeast exists in small numbers without causing problems. However, when the ear environment changes, yeast can multiply rapidly and lead to inflammation and infection.
These infections most often affect the external ear canal (a condition known as otitis externa), but if left untreated, they can progress deeper into the ear and become more serious.
5 Common Signs and Symptoms of Ear Infections in Dogs
Yeast infections tend to have very recognisable signs. Owners often notice:
- Persistent head shaking or ear scratching
- Red, inflamed ear canals
- Thick discharge that may appear brown, yellow, or black
- A strong, musty, or “yeasty” odour
- Sensitivity or pain when their ear is touched
If the infection becomes chronic, the ear canal may thicken, narrow, or develop long-term inflammation, so make sure to take your dog to the vet if they have any of these symptoms.
Why Do Yeast Infections Develop in Dog Ears?
A dog’s ear canal is L-shaped, which limits airflow and makes it easier for moisture, heat, and debris to become trapped. Yeast thrives in warm, dark, and moist environments, making the ear canal an ideal place for overgrowth under the right conditions.
Common triggers include:
- Excess moisture from swimming or bathing
- Allergies (environmental or food-related)
- Hormonal imbalances
- Changes in ear pH
- Excess ear wax production
Rather than being a standalone disease, ear yeast infections are often a secondary problem caused by an underlying issue.
What Kind of Dogs Are Prone to Ear Yeast Infections?
While any dog can develop a yeast ear infection, some are more predisposed than others. Look out for your dog’s ears if they have the following characteristics:
- Floppy or hairy ears, which reduce air circulation
- Dogs with allergies, especially chronic skin allergies
- Frequent swimmers or dogs bathed often
- Underlying medical conditions such as hypothyroidism or Cushing’s disease in dogs
- Breeds prone to ear issues, including Cocker Spaniels, Basset Hounds, Bulldogs, and Poodles.
Yeast vs. Bacterial Ear Infections in Dogs
Yeast infections are frequently confused with bacterial ear infections, and the two can occur together. While symptoms can overlap, yeast infections often have:
- A stronger odour
- Greasy, black or waxy discharge
- More intense itchiness
From a veterinary perspective, identifying the correct cause is critical, as treatments differ. This is why vets often examine ear samples under a microscope before prescribing medication.
While it’s tempting to rely on past experience, treating a yeast infection with antibiotics won't work—and vice versa. Always consult your vet for a professional exam to ensure your dog receives the correct prescription.
How to Prevent Dog Ear Yeast Infections
Preventing dog ear yeast infections is less about quick fixes and more about controlling the environment and underlying triggers that allow yeast to overgrow. From a veterinary standpoint, long-term prevention focuses on ear health as part of your dog’s overall wellness—not just reacting when symptoms appear.
Below is a practical, vet-informed approach to prevention, with specific strategies you can tailor to your dog.
Avoid Over Cleaning Your Dog's Ears
Routine ear cleaning helps remove excess wax and debris that yeast feeds on. However, overcleaning can be just as harmful, as it may irritate the ear canal and disrupt the natural protective barrier.
Best practices include:
- Use a vet-approved ear cleaner designed to maintain proper ear pH
- Clean only as often as recommended for your dog’s ear type and lifestyle. Discuss this with your veterinarian.
- Avoid cotton swabs deep in the ear canal, which can push debris further inside
Dogs with chronic issues often benefit from maintenance cleaning schedules rather than sporadic cleaning only when problems arise.
Control Moisture After Swimming or Baths
Moisture is one of the strongest drivers of yeast overgrowth. Any dog that swims, plays in water, or is bathed frequently needs extra attention to ear drying.
Helpful prevention steps:
- Gently dry ears after water exposure using a clean towel
- Use drying ear solutions if recommended by your vet
- Avoid leaving ears damp, especially in dogs with floppy or hairy ears
Even small amounts of trapped moisture can create the perfect environment for yeast to multiply.
How to Proactively Address Dog Allergies
From a veterinary perspective, allergies are the number one underlying cause of recurrent yeast ear infections. Treating the ears alone will not prevent repeat episodes if allergies are left unmanaged.
Preventive allergy management may involve:
- Identifying and avoiding environmental allergens
- Conducting food trials if food allergies are suspected
- Using vet-prescribed allergy medications or immunotherapy
When allergies are controlled, ear infections often become far less frequent—or stop entirely.
Maintain Proper Ear Hair and Airflow
Dogs with heavy ear hair or tightly folded ears often experience reduced airflow, which traps heat and humidity.
Depending on the breed and individual dog:
- Excess hair around the ear opening may need regular trimming or plucking
- Grooming schedules should be adjusted for dogs prone to ear issues
- Ear conformation should guide prevention strategies, not a one-size-fits-all approach
Your vet or groomer can advise what is appropriate for your dog’s specific ear anatomy.
Support Overall Skin and Immune Health
Healthy ears start with healthy skin. Conditions that affect the immune system or skin barrier can indirectly increase the risk of yeast overgrowth.
Preventive care includes:
- Balanced, high-quality nutrition
- Managing hormonal conditions such as hypothyroidism
- Regular veterinary checkups to catch early changes
When the skin is resilient, yeast is less likely to overgrow—even when exposed to triggers.
Don’t Ignore Early Warning Signs
Catching and addressing a yeast ear infection early not only provides faster relief for your dog but also helps prevent chronic ear disease and long-term damage to the ear canal. Repeated infections are a sign that an underlying cause needs to be identified and managed—not just treated on the surface.
Catching issues early allows:
- Shorter treatment courses
- Less discomfort for your dog
- Reduced risk of chronic ear disease
If your dog has a history of ear infections, routine ear checks at home can make a significant difference.
Vet Tip
For recurring yeast ear infections, have your vet check your dog’s ears between flare-ups—early changes often reveal the underlying cause and help prevent repeat infections.
Browse our vet-recommended ear cleansers for dogs
PAW Gentle Ear Cleaner
PAW Gentle Ear Cleaner is a natural, gentle ear cleaner that effectively cleans your pet's ears without irritation.
Its effective formulation means you only need to use it once a week, making it more comfortable for your pet and easier for you. It contains:
- Purified hydrolysed oats for a mild, effective product for cleaning your cat or dog’s ears.
- No alcohol, harsh chemicals or acids commonly found in other cat or dog ear cleaners, so it’s more comfortable for your pet.
Sonotix Ear Cleaner
Sonotix® is an enhanced ear cleaner that balances ear pH and helps restore the skin barrier. When used with the most problem-prone dogs and cats, it can support long-term ear health and help manage recurring issues.
Sonotix® contains ingredients that contribute to the balance of the ear, including lipacides that aid in sebum regulation, and can be part of an ear cleaning regimen to be determined in collaboration with your vet. It's important to always follow proper practices for ear cleaning - always chat to your vet if you are concerned that your pet is showing signs of being in pain.
Sonotix® saves time through thorough ear cleaning, every time and is water-based so it doesn't leave behind any oily residues.
- Moisturising & Soothing
- Sebum Regulation
- PH Balanced Formula
- Preservative & Paraben Free
Vetsense Otiderm Ear and Wound Cleanser
Vetsense Otiderm aids in the removal of dead tissue and embedded debris by causing maximum differential swelling between living and dead areas.
This is achieved in two ways;
- Low pH causes separation of collagen molecules by rupturing the hydrogen bonding. The optimum pH to achieve this effect is between pH2 and pH3.
- The organic acids react with carboxyl and amino groups in the collagen. The insertion of the organic acid forces the collagen chains apart. In both cases, the devitalised tissues absorb water and swell. Healthy tissues are unaffected because of natural barriers to the organic acids and sufficient buffering capacity to maintain a near neutral pH.
Conclusion
Dog ear yeast infections are common but manageable. By addressing underlying causes like moisture and allergies, maintaining proper ear care, and acting early when signs appear, many infections can be prevented. Working closely with your veterinarian helps protect your dog from recurring discomfort and long-term ear damage.
This article was written by Dr Jane Miller
References
1. Veterinary Partner. Ear Infections (Yeast Otitis) in Dogs. Veterinary Information Network (VIN). Available at: https://veterinarypartner.vin.com/default.aspx?id=8621491&pid=19239
2. AKC Staff. Dog Ear Infections: Symptoms, Causes, Treatment, and Prevention. American Kennel Club. 2025. Available at: https://www.akc.org/expert-advice/health/dog-ear-infections/
3.“FDA Approves Treatment for Yeast Ear Infections in Dogs.” U.S. Food & Drug Administration (FDA). Available at: https://www.fda.gov/animal-veterinary/cvm-updates/fda-approves-treatment-yeast-ear-infections-dogs
4. Houston D. Malassezia Otitis in Dogs and Cats: Ear Yeast Infections Explained by a Vet (2025). Ask a Vet. Available at: https://askavet.com/blogs/news/malassezia-otitis-in-dogs-and-cats-ear-yeast-infections-explained-by-a-vet-2025
