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Ear disease and infections are one of the most commonly observed pet health problems seen in the veterinary clinic. Veterinary dermatologists are uniquely qualified to treat ear infections in dogs and cats. Many skin diseases will manifest in a pet’s ears as well. In the veterinary world, veterinary dermatologists are the otologists or ear specialists. Dermatologists have tools for treating recurrent, severe or inner ear disease that primary care veterinarians typically do not have in their hospitals including specialized cameras, scopes, surgical tools and video guided deep ear flush machines. Dermatologists have also “seen it all” and know the best strategies for treating your individual pet’s ears while taking into account their breed, temperament, medication sensitivities, severity of disease and owner’s preferences. There are many strategies for treating ear disease and a treatment for one pet will not necessarily work for another. Managing ear infections is an art form, and with years of experience and thousands of ear infections/issues treated, we will be able to get your pet on track and provide relief from the misery of itchy, uncomfortable and painful ears.

What is an ear infection?

An ear infection, or infectious otitis, is an infection caused by bacteria, yeast and/or fungus that can make your pet miserable and predispose your pet’s ear to chronic damage and changes. Chronic ear infections can be the result of many underlying health issues, and it is vital to get to the bottom of what is causing them instead of just putting band-aids on the problem. The following are the most common causes of ear infections in dogs and cats:

  • Allergies (environmental and food)
  • An object in the ear canal (tumors, parasites, foreign material)
  • Autoimmune disorders
  • Endocrine disorders
  • Anatomy (having small ear canals or excess hair)

Ear infection symptoms

Clinical signs can vary depending on the severity and location of the infection. Please note, some pets have one or many of the below clinical signs of ear disease or otitis.

Symptoms of outer ear disease (otitis externa):

  • Head shaking
  • Itchy ears (scratching or rubbing ears or side of face)
  • Red ears (ear flap or entrance of canals)
  • Swollen ears
  • Smelly ears
  • Crusting to ears
  • Ear debris
  • Discomfort when patting their head
  • Yelping when ear is touched (pain)
  • Lower ear carriage (not raising ear or ears, not perking up their ears when they hear something)
  • Ear canals that feel hard, almost bone-like, which indicates chronic disease

Symptoms of inner ear disease (otitis media):

  • Any of the signs for outer ear infections
  • Recurrent outer ear infections
  • Hearing loss
  • Head tilt to one side
  • Imbalance
  • Nystagmus (eyes going side to side)
  • Closing or squinting of one eye
  • Horner’s syndrome (constricted pupil of the eye on the same side as the ear infection)
  • Any neurological clinical signs which can indicate significant middle ear or inner ear disease.
  • Food falling out of one side of the mouth (due to secondary nerve inflammation)
  • Nausea (intermittent vomiting)
  • Lethargy
  • Fever
  • Elevated white blood cell counts

Causes of ear infections

  • Allergic Otitis: One of the most common sources of ear infection is allergies. Allergies cause inflammation of the skin lining the ear canal which then can lead to the overgrowth of infectious agents like yeast and bacteria. This infection causes more inflammation, exudate or wax production, and pain causing the pet to scratch, rub, and shake their ears.
  • Outer Ear Infections: Causes of outer ear infections include: narrow ear canals (seen in shar-peis, pugs, French bulldogs, English bulldogs, etc.), hair-filled canals seen in poodles and doodles, floppy ears seen in hound dogs, ear mites, foreign bodies (ex: foxtails), obstructions (ex: polyps, growths, masses), and reactions to products or solutions placed on or in the ear.
  • Middle Ear Infections: Infection within the bulla (middle ear bone) can occur from an infection that has eaten through the ear drum or can be a primary infection or sterile build up within the ear leading to secondary infection. A few dog breeds have genetic anatomic changes that predispose them to middle ear disease like the Cavalier King Charles spaniel, English bulldog, French bulldog, cocker spaniel, boxer, pug and Boston terrier.

Ear infection diagnosis


  • A detailed conversation and or questionnaire about your pet’s ear disease is essential in getting to the root cause of why your pet’s ears are suffering. A veterinary dermatologist will spend extensive time asking specific questions and gathering detail which will be used to formulate your pet’s diagnostic and treatment plan. Key points of discussion will be: age of onset, frequency of ear disease or length of current infection, and what treatments have already been tried.
  • If ear infections resolve, it is also important to establish whether this was confirmed by a follow-up otoscopic examination or is merely the owner’s observation that clinical signs have resolved (as opposed to resolution of infection). If resolution of previous ear disease was not confirmed by a veterinary examination, establishing seasonality becomes impossible.


  • After obtaining a detailed history, a complete dermatologic examination should be performed in any dog suffering from ear disease. This includes lip folds, neck fold, arm pits, in between toes, base of toe nails, peri-anal and peri-genital skin exam. Pets with ear disease frequently have clinical signs affecting their skin that also need to be identified. These clues and patterns of ear and skin disease are used to provide the owner and patient with a diagnosis or a differential diagnosis list of disease affecting the pet.
  • To avoid missing abnormalities, a complete otic examination will be performed.
  • A hand-held otoscope with clean cones is used to look into both ears. A skilled otoscope user may be able to show an owner what is occurring through the scope. A veterinary dermatologist can also use a video otoscope to allow an owner to see a detailed visualization of their pet’s ear.
  • Since the presence of pain can limit proper evaluation of the ear canal, the dog should be evaluated for pain, and sometimes light sedation is needed before the otoscopic examination is performed.
  • The next step is to determine whether concurrent middle or inner ear disease is present. Since the nerves in the middle ear are next to facial nerves, a neurological exam must be performed.


  • Cytology is one of the most important tests we perform. Cytologic examination involves taking a sample from within the ear canal to look for types of infection and amount of debris under a microscope.
  • Bacterial culture may be needed when a pet has failed to respond to appropriate empirical antimicrobial therapy or in cases with deep middle ear infections.
  • Skin biopsies or mass submission for histopathology from the ear or ear canal can also be necessary in some cases.
  • CT scan can be used to evaluate for middle/inner ear infections as well as deep ear tumors and growths.

Ear infection prevention

  • The most important steps to prevent ear infections is identifying the root cause or disease leading to the infection and resolving or managing this cause.
  • For mild ear infections, some dogs will respond to weekly cleaning of the canals with mild ear cleaners. Consult with your veterinarian with the ideal ear cleaner because the ingredients all have different purposes. Thus, one ear cleaner may be better for a particular case than another.
  • If your pet experiences ear redness, itch or infections for a few weeks at a certain time of year, working with your primary veterinarian or veterinary dermatologist on a prevention plan to get through the short season is an option. Sometimes, this can consist of increased cleaning, short courses of topical ear medications or short courses of oral anti-inflammatory medications.
  • For patients experiencing prolonged or multiple recurrent infections, consulting with a certified veterinary dermatologist is advisable.

Ear infection treatments

The doctor will carefully examine a sample of what is in your pet’s ear under a microscope, and depending on the severity of the case, possibly submit a sample for culturing. Each dog or cat is unique, and each instance of infection is unique. If your pet had an ear infection six months prior and has another bout of infection, it could be a different type of bacteria or yeast involved and require a different medical plan. There are many different treatment options available, and your pet may respond the best to a combination of various treatments. These include topical medications, systemic medications and ear cleaners.

If the ear infection is a result of allergies, treating the source of allergies, in many cases, will resolve recurrent ear infections. The gold standard for allergy therapy is the use of immunotherapy (allergy shots) or a diet made for dogs with food allergies. Unfortunately, many dogs who have recurrent ear infections take anti-itch medications which can mask the itchiness a dog experiences while not stopping the infection. If a recurrent ear infection is not addressed, it can lead to loss of hearing and infections deeper in the skull which can lead to neurologic defects (head tilt, loss of balance, facial paralysis, loss of blinking eye) that could require surgery for complete removal of the ear. Anti-itch medications serve a valuable purpose in improving the quality of life for many pets, but it is important not to just mask severe underlying issues.

What can happen if a pet’s chronic ear disease is improperly managed or ignored? What is the worst-case scenario?

When ear disease is chronic, it can lead to permanent ear canal narrowing, glandular tumor formation, scar formation and calcification (when the ear becomes bone-like). These conditions may require a costly ear ablation surgery, which is the complete removal of the ear canal which results in deafness in the affected ear.

Chronic ear infections can also damage the facial nerves and create neurological problems for pets.

If the ear infections are due to masses or growths, it is imperative that they are surgically removed for rapid diagnosis. Removing ear growths, while small, can prevent secondary long-term problems that develop like chronic ear changes. Also, gaining a diagnosis of cancer can potentially lengthen your pet’s life. Many cancers are malignant and can quickly spread throughout the body if left unchecked. After diagnosis of a malignant cancer, we can provide quick referral to a veterinary surgeon or oncologist so removal or focused radiation can be performed.