Ear yeast infections are very common in dogs. Dogs with floppy or hairy ears are particularly vulnerable because their ears trap moisture. The moist environment of the ear is a prime breeding ground for fungal yeast that, when overgrown, creates an infection. This causes itching, inflammation, and an unpleasant odor. Untreated, neglected ear infections can lead to painful skin crusting and other complications and serious problems that can affect the ear canal lining and even lead to facial paralysis. So it's helpful to know how to spot—or sniff—the symptoms.

What Is an Ear Yeast Infection?

An ear yeast infection occurs when yeast species overpopulate the ear of a dog. Malassezia pachydermatis is the species of yeast that is typically seen in dog ears. This type of yeast is different than the yeast that is used to bake bread or that is found in probiotics. It is naturally found on the skin and ears of dogs in very small amounts but if the right conditions are present to cause inflammation, the result will be a noncontagious infection.

Symptoms of Ear Yeast Infections in Dogs

Luckily, signs of ear yeast infections can be easily spotted so if you see any of the following signs, visit the vet.

Shaking Head and Scratching at Ears

Similar to a bacterial infection of the ear, a yeast infection usually causes a dog to shake its head and scratch at its ears. This is due to the irritation and inflammation that the infection causes.

Painful Ears

Your dog may also be reluctant to have its head and ears touched due to discomfort.

Red or Swelling Inside Ears

Inside the ear there may be redness and swelling, both of which may indicate a yeast infection.

Yeasty Odor From the Ears

An odor similar to sour bread dough may be present if your dog has an ear yeast infection.

Excessive Ear Wax or Debris

If you spot oily ear debris in your dog's ears, it means its canals are inflamed and the possibility it has an infection.

Thickened Ear Flaps

The ear canal and the ear flap itself can both be affected. The condition may cause thickening of the skin on the ear flap.

Ear Skin Scaling

Scaling or crusting of the skin on the ear flap is also common, especially in severe or chronic cases.

Drooping Ear

If you notice that your dog is walking around with a drooping ear, or holding one side of its head lower, it may mean your pet has had an ear infection for a while. Your dog may have learned to adapt to the discomfort by lowering an ear.

Trouble With Balance

If the infection is causing neurological problems, you will notice your dog walking off balance. This usually means the inner ear is affected.

What Causes Ear Yeast Infections in Dogs?

There are several causes of ear yeast infections in dogs. Some are more serious than others.

Allergies

If a dog has an allergy to something in the environment or food then a yeast overgrowth may occur in the ear. The body reacts to the allergen with inflammation, and this, in turn, can cause the yeast to proliferate in the ear.

Ear Mites

Ear mites, which feed off of a dog's ear wax, can cause irritation and inflammation in the ear. This can result in an overgrowth of yeast.

Moisture

An ear canal is a warm place, and yeast thrives in warm, moist environments. If water enters the ear canal during a bath, for example, and the ears do not properly dry out, yeast will reproduce and cause an infection.

Ear Deformities

Some dogs are born with abnormal ear canals or excessive ear tissue. Other dogs will develop ear issues over time due to trauma, recurrent infections, or other things. These deformities usually make it difficult for an ear to stay dry and instead trap moisture that helps to create an environment for yeast to grow in.

Tumors

Some tumors in the ear block the opening to the ear canal. This causes excessive heat and moisture to build up and encourages the overgrowth of yeast.

Medications

If your dog is taking certain medications, such as antibiotics or corticosteroids (steroids), the medicines may inhibit your dog from effectively fighting off yeast infections.

How Do Vets Diagnose Ear Yeast Infections in Dogs?

If you suspect there's a yeast infection in your dog's ears, have it examined by a veterinarian. Your vet will use an otoscope to see inside the ear canal and make sure the eardrum isn't ruptured. A cotton swab will then be used to collect some of the ear debris for microscopic examination to see if yeast, bacteria, or both are present. A dark discharge may mean an ear yeast infection, mites, or a mixed infection, but your doctor will check for more evidence of mites.

How to Treat Ear Yeast Infections

Your vet will prescribe medicated ear drops and a cleaner to remove the debris. These will be used for about two weeks. If the ear is especially painful, then anti-inflammatory medications may also be used.

Occasionally an ear yeast infection may be so painful for a dog that it will need to be sedated or anesthetized by your vet to perform the initial ear cleaning and treatment. Your veterinarian may also recommend some at-home remedies depending on the severity of the infection.

Your vet may suggest clipping the hairs around the ear to improve comfort and cleanliness during treatment and recovery.

Prognosis for Dogs with Ear Yeast Infections

Yeast infections are usually easy to treat with persistent treatment. In dogs with predisposing characteristics, such as floppy ears, allergies, or ear deformities, the condition is likely to reoccur since they are at a higher risk of recurrent ear yeast infections.

Many breeds, including cocker spaniels and basset hounds, have floppy ears that cut off air to the ear and should be maintained to keep infections at bay. Other breeds need observation as well, such as poodles (also with floppy ears) and schnauzers may have thick hair growth inside their ears that can block the flow of air in the ears and keep them overly moist. In addition, dogs that like to play in water are also potentially more likely to experience a recurring yeast overgrowth and infection.

How to Prevent Ear Yeast Infections

The best way to prevent your dog from developing an ear yeast infection is to keep its ears clean and dry. An ear cleaner with a drying agent should be used after baths and swimming to help dry the ear canal. If your dog has allergies, your veterinarian may recommend certain foods and supplements to help support the skin and decrease inflammation.