As a part of your dog's routine physical exam, your veterinarian will look into their ear canal using a lighted tool called an otoscope. If your vet notices that your dog has any discomfort, redness in the ear canal or excessive debris, these are clues that an ear infection is lurking.
A dog ear yeast infection usually occurs when there's an excess of moisture in their ear. It typically begins in the outer ear canal (or the otitis externa) but can progress to involve the middle ear canal (otitis media) and inner ear (otitis interna) if left untreated. Let's explore some of the clinical signs of a dog ear yeast infection and the difference between dog ear mites versus yeast infection.
When it comes to otitis, dogs can show both physical and behavioral signs. Ear infections don't resolve on their own and can worsen rapidly; therefore, if you notice any of the clinical signs from either list below, schedule a veterinary appointment right away.
Physical clinical signs include:

More behavioral clinical signs of otitis that pet parents should be aware of include:
*These signs aren't observed with the majority of ear infections, but they are often associated with an infection that involves the inner or middle ear.
Because the dog's ear is a warm, humid environment, it's a natural breeding ground for yeast and bacteria. Any number of factors can lead to an imbalance of yeast or bacteria, regardless of sex, ear shape, history of exposure to water (swimming) or the amount of hair inside the ear canal. Dog breeds with droopy ears, such as basset hounds; oily coats, such as cocker spaniels; and breeds known for allergies, such as Labrador retrievers, are known to suffer from severe or recurring dog ear yeast infections. Allergens are believed to be a significant contributor to the inflammatory and infectious cycle of ear infections.

Dog ear mites are more common in puppies and dogs with weakened immune systems, but they may also occur in healthy adult dogs. Dogs of all ages can develop both bacterial and yeast-based ear infections.
While most dogs will experience an ear infection at least once in their lifetime, dog ear yeast infections are often the result of an underlying issue. According to the Canadian Veterinary Journal, some of these factors include: