Ear Mites or Infection?

Posted on by Christopher Bern, DVM

Here’s a common scenario: A client notices a lot of debris and odor in their dog’s ears. The dog is also shaking her head and scratching the ears, which obviously concerns the owner. They go down to the local pet store, pick up some over-the-counter ear mite medication and start treating. After a week or two the problem is still there and the medicine didn’t seem to work at all. Why not?

Because it’s actually very uncommon to find ear mites in dogs.

Ear mites are a small, almost microscopic organism related to spiders and ticks. They cause significant irritation to the ear canal, which leads to an overabundance of dark debris that is a mixture of secretions, mite feces, and dead skin cells. The mites cause intense itching, leading to scratching and shaking the ears. Mites are arguably the most common cause of ear irritation in cats, but not in dogs. I see a case of ear mites in dogs maybe a couple of times per year, whereas I see infections almost daily, especially during warm weather.

In the huge majority of dogs, if there is debris, odor and itching of the ears, an infection is present. There are a number of reasons infections can occur, including underlying allergy disorders (food, pollen, mold, grass, etc.), excessive moisture in the ears, ear structure (heavy, floppy, hairy ears) and so on. If an infection happens two or more times in a 12 month period, it is considered a symptom of a greater problem and the underlying cause needs to be addressed. Several types of bacteria, as well as yeast, can be found as the infectious organism, and proper identification is important in determining the proper medicine used in treatment. There is no way to tell by doing a simple physical exam whether the infection is rods, cocci (different types of bacteria), yeast, or a mixture of these.

It’s also very important to have your pet’s ears cleaned if mites or an infection are present. The debris can make it difficult for the medicine to reach the skin and can even inactivate some of the ingredients. Your vet can do a more thorough job of cleaning the ears (which may require sedation), but it’s necessary to continue cleaning the ears for 1-2 weeks during the treatment at home. Talk to your vet about the proper way to clean ears. You can also find additional information on cleaning in the Banfield pet health library.

So what do you do? How do you tell the difference between an infection and mites?

Go to the vet and have an ear exam and swab performed. Sometimes, we can see mites with even the small magnification on our otoscope, but we need to get a sample of the debris and look under the microscope to be certain. It’s also not uncommon to see an infection secondary to the mites, requiring more than one medication. Proper identification of the mites or microorganisms will allow faster and more effective treatment. It’s also important to follow your vet’s advice for follow-up exams to see if the infection has resolved. While most infections can be treated in about two weeks, some require 4-6 weeks of continual treatment. Improper or incomplete treatment can result in persistent pain and even permanent damage to the ears.

About Christopher Bern, DVM

Dr. Bern has been with the practice since 1999 and currently works as the Chief of Staff for the Woodstock, GA hospital. View all posts by Christopher Bern, DVM →

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