Middle and Inner Ear Infections in Dogs

A middle ear infection is also called otitis media and generally results from an infection that has spread from the outer ear. Mites in the outer ear can migrate into the middle ear and cause a bacterial infection. Fungal infections can also infiltrate the middle ear.

An inner ear infection is called otitis interna and generally results from a bacterial infection; although yeast (a fungus) can also contribute to an inner ear infection. Just like the middle ear, mites can migrate to the inner ear creating a problematic environment for an infection.

All dogs are prone to ear infections; however, there are specific breeds that are more prone to middle and inner ear infections. Dogs with drooping ears such as the Beagle, Dachshund, Basset Hound and Cavalier King Charles Spaniel need to have their ears closely monitored for signs of infection. Dogs with narrow ear canals, such the Cocker Spaniel and the Shar-Pei, and dogs with hairy inner ear canals, such as the Poodle and Schnauzer, can also be more susceptible to middle and inner ear infections.

Your dog’s ear consists of three main parts: the outer ear, the middle ear and the inner ear. Infections within the middle and inner ear must be treated quickly to prevent recurrence and permanent damage to your dog’s ear or nerves within the face on the affected side.

There are several signs that may indicate that your dog has an ear infection. If you notice any of these signs, make an appointment with your veterinarian to determine which part of the ear is affected and to provide the proper treatment of the infection.

Ear Infection of Outer, Middle & Inner Ear

• Shaking of the head
• Scratching at the ear
• Scratching under the ear or near the cheek
• Rubbing the ear on the ground or other objects
• Cocking the head to one side
• Discharge from the ear
• Foul smell coming from the ear
• Whining or crying

Middle or Inner Ear Infection

• Vomiting or nausea
• Drooling from the side of the mouth on the affected side 
• Dropping food out of their mouth or difficulty eating
• Unable to blink
• Eye discharge
• Eyelids, lips, or nostrils that droop on the affected side
• Symptoms of Horner’s Syndrome occur
• Falling or leaning toward the affected side
• Walking in circles towards the affected ear
• Thick discharge from the affected ear
• Sudden hearing loss in the affected ear
• Inflamed ear canal; oftentimes a bright red color
• Pain when the ear is touched
• Eyes darting back and forth (nystagmus)
• Nerve paralysis in the face

There are many causes of middle and inner ear infections. Many times the outer ear infection is not properly treated and then migrates to the middle ear and possibly the inner ear causing significant pain problems for your dog. Your veterinarian can run certain tests if your dog experiences chronic middle and/or inner ear infections to determine the specific cause of the infections.

Allergies have been determined to be the most common cause of recurring ear infections. If the allergen is not identified and the allergic reaction persists, it will be almost impossible to resolve the ear infections and can cause irreversible damage to the affected ear or ears.

• Cleaning the ears too often
• Not cleaning the ears well enough
• Water in the ear
• Excessive humidity
• Allergies (food or environmental)
• Antibiotics
• Hypothyroidism
• Ear mites
• Bacterial and/or yeast overgrowth
• A foreign body such as a grass seed
• An ear polyp

While it is fairly easy to diagnose an outer ear infection, it can be trickier to identify a middle or inner ear infection. Veterinarians will examine the ear canal and can usually identify if inflammation is present within the ear canal.

Your veterinarian will diagnose a middle or inner ear infection based on previous history and any present clinical signs. Dogs that are prone to ear infections should be checked on a regular basis for any changes to the ear. This will allow treatment to start quickly to combat the infection and keep it from progressing into a severely painful situation for your dog.

A swab for cytology and a culture and sensitivity test may be taken.

Diagnostic imaging such as a CT scan can also be useful for assessing the tympanic bullae.

Early detection of a middle or inner ear infection is the best way to control the infection. Your veterinarian will treat the ear infection to prevent the infection from causing long-term effects such as deafness. 

Treatment will involve thoroughly cleaning the affected ear and then flushing the affected ear with a saline solution. Some veterinarians may clean and flush both ears, even if only one ear is affected. In extreme cases, your dog may need to be anesthetized to thoroughly clean the ear, especially if they are in a lot of pain. This allows the tympanic membrane to be visualised.

An antibiotic, antiparasitic or antifungal medication will usually be prescribed. In some cases a steroid may also be prescribed to reduce inflammation within the ear. Always give the prescribed medications as directed and any questions regarding the medication and possible side effects should be directed to your veterinarian.

A myringotomy should be performed for deeper ear infections and swabs should be taken before flushing.

When a middle or inner ear infection is treated quickly, most dogs respond to treatment and do not have long-term effects. If the infection was not diagnosed and treated quickly, long-term effects such as deafness and an altered sense of balance may result. If your dog’s balance was affected by an inner ear infection, you can expect to see improvement within two to six weeks following the initial diagnosis and treatment. 

Follow your veterinarian’s instructions closely and complete all follow-up visits to ensure that the infection has been properly treated. Your veterinarian will discuss possible continued care should your dog be prone to middle and/or inner ear infections.

Middle and inner ear infections can be expensive to treat. To avoid high vet care expenses, secure pet health insurance today. The sooner you insure your pet, the more protection you’ll have from unexpected vet costs.