Dog Otitis Externa – How To Prevent Ear Infection

Ear Infection and Protection

Acute otitis externa is predominantly a microbial infection. It occurs rather suddenly, rapidly worsens, and becomes very painful and alarming. It is the predominant complaint and the only symptom directly related to the severity of acute external otitis.

Otitis externa is an inflammation of the outer ear and ear canal. Inflammation of the skin of the ear canal is the essence of this disorder. The inflammation can be secondary to dermatitis (eczema) only, with no microbial infection, or it can be caused by active bacterial or fungal infection.

In either case, but more often with infection, the ear canal skin swells and may become painful and/or tender to touch. Unlike other forms of ear infections, the pain of acute external otitis is worsened when the outer ear is touched or pulled gently.

External Otitis

The two factors that are required for external otitis to develop are

  1. The presence of germs that can infect the skin, and
  2. Impairments in the integrity of the skin of the ear canal that allow infection to occur.

Ear disease is one of the most common conditions we see in pets. It is estimated that up to 20% of the dog population is affected by this disease.

Commons Signs Of Ear Infection

The most common signs of ear infection of otitis externa include bad ear odor, discharge of the ears, or dog shaking his head or he tilts his head to one side.

dog at vet
Image credit: Openverse

If you also notice your dog is scratching or rubbing of ears and head, check for the ear’s redness or swelling of the ear flap or canal, slowly check if your dog could feel pain around his ears.

Also some changes in dog’s behavior like depression or irritability are observed. Some animals may also paw the ear or try to rub it on other objects to relieve pain and discomfort. Ear infections often result in a darker red ear, dirt in the ear, or a general inflamed appearance.

Dogs with progressive pathologic changes in the ear canal my turn into this disease and proper pet safety practices should immediately observed..

Dogs with noticeable allergies to his foods, to his environment, or to something he inhales, might often have ear problems. As a matter of fact, the ear problem may be the first sign of the allergy.

Since the allergy changes the environment within the ear, we sometimes see secondary infections with bacteria or yeast. If we just treat the infection, we are not getting to the root of the problem. We need to treat the allergies too.

Causes Of Ear Infection

Otodectes cynotis or dog ear mite is also major cause of ear infection but most commonly observed to occur on cats and rare for dogs. Some dogs are hypersensitive (Hypersensitivity disorders or Keratinization disorders) to the mites, however, and the resultant itching can be intense. These dogs may scratch so much they severely traumatize the ear.

varroa, mite, bee parasite
“Mite” Image credit: Olivier Levoux | Unsplash

Numerous types of bacteria and the yeast, Malassezia pachydermatis, cause ear infections. The normal, healthy ear has a good defense against these organisms, but if the ear environment changes due to allergies, hormone abnormalities, or moisture, the bacteria and yeast can greatly multiply and break down these defenses.

Hormonal abnormalities like deficiencies or excesses of various hormones can result in skin and ear problems. Thyroid hormone, glucocorticoids produced by the adrenal gland, and sex hormones all influence the health of the skin and ears.

Plant awns, those little “stick-tights” that cling to our clothes and our dogs’ fur, can sometimes enter the ear canal. Their presence causes irritation, the dog scratches, and before you know it we have a traumatized, infected ear So when you groom your dog after a walk in the woods, be sure to check the ears, too.

sticker bush, thorn bush, seed
Image credit: Scottslm | Pexabay

There are various rare hereditary diseases that occur in different breeds or lines and affect the ears. These include dermatomyositis in Collies and Shetland Sheepdogs, and primary seborrhea in Shar Peis and West Highland White Terriers. Squamous cell carcinomas, melanomas, and other tumors can be seen in the ears.


In mild cases, a product with anti-inflammatory, anti-fungal and anti-bacterial ingredients are often employed. In more severe cases, ear cleaning under sedation or anesthesia may be required and evaluation for otitis media may be indicated.

Treatment for ear mites include ear drops that contain pyrethrins or an avermectin such as ivermectin or selamectin. Cleaning of the ears is very important for treatment of ear infections.

Cleansing and antiseptic mixtures are made from isopropyl (rubbing) alcohol, boric acid and acetic acid (vinegar) in various proportions. In some recipes, povidone-iodine (betadine) is added as well. Treatment regimen for fungal ear infections includes ketoconazole, and miconazole both topically as well as orally.

However, despite the advancement in the therapeutic approaches, otitis externa can be resistant to antifungal antibiotics. Emergence of drug resistance is an important contributing factor.

In view of these facts, herbal ear preparations may be of therapeutic efficacy in the treatment of otitis externa in dogs. A number of antibacterials have been suggested for use and have been found to be effective in the treatment of otitis externa and these include gentamicin, sulphadiazine in combination with trimethoprim, ampicillin, ampicillin in combination with cloxacillin, enrofloxacin, amoxycillin, cephalexin and cefadroxil.

Apart from antimicrobials, ear infection require treatment for associated itichiness and other inflammation related signs using steroidal drugs like prednisolone, dexamethasone and non-steroidal anti-inflammatory drugs (NSAIDs) like clemastine fumarate, diphenhydramine hydrochloride, pheniramine maleate et cetera.


For prevention, cleaning dog ears is very important as well as the place where they usually stay like in their dog crates. Your dog’s ear is more L-shaped than yours, and debris loves to collect at the corner of the L. To remove this debris, fill your dog’s ear canal with a good ear cleaner. Ear cleaners should be slightly acidic but should not sting.

dog ear bath
Image credit: Openverse
  • Massage the base of the ear for 20-30 seconds to soften and release the debris. Wipe out the loose debris and excess fluid with a cotton ball.
  • Repeat this procedure until you see no more debris.
  • Depending on your dog’s ear condition, you may have to start out doing this twice a day.

Cotton applicator swabs can be used to clean the inside of the earflap and the part of the ear canal you can see. They should NOT be used farther down in the ear canal since that tends to pack debris in the ear canal, rather than removing it. Some ear problems are so painful, the dog must be anesthetized to do a good job of cleaning the ears.

You may find your dog does not like to have his ears cleaned because it is uncomfortable. Talking to him during the process, stopping momentarily to give him a treat if he is doing well (we do not want to reward fussiness!) and doing something fun afterwards may all help.

Remember, if your dog is showing severe discomfort, the ears have a bad smell, or the ear canals look very abnormal, do not delay in contacting your veterinarian. If your dog has a ruptured or weakened eardrum, some ear cleansers and medications could do more harm than good.


  • Hannah Serrano

    The guest author is a passionate dog lover and enthusiast with years of experience in canine care and training. With a deep understanding of dog behavior and a commitment to promoting responsible pet ownership, the author shares insightful tips and engaging stories to enrich the lives of both dogs and their owners. The views and opinions expressed in articles written by guest authors on our website are their own and do not necessarily reflect the views or opinions of our platform.

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