Are you looking for a way to help your dog with chronic ear infections? Ear infections in dogs are a common occurrence where most dogs will develop at least one ear infection in their lifetime. Some dogs however develop chronic ear infections where they have multiple bouts throughout the year. This article will discuss the reasons why your dog is having chronic ear infections and how you can manage them. In most dogs, the most common reason for chronic ear infections is allergies but it could also be a result of their ear canal anatomy or tumors and polyps. After reading this article, we hope you have a better understanding of why your dog has chronic ear infections and what you can do to help!

What are chronic ear infections in dogs?

Your veterinarian will refer to ear infections as otitis externa which is a result of infection and inflammation of the ear canal in dogs. Ear infections can be a result of bacterial, fungal (yeast), or parasitic infections. Most veterinarians will define chronic ear infections as the dog developing an ear infection multiple times (~4-6) per year.

What are the causes of chronic ear infections in dogs?

There are many causes of recurring, chronic ear infections, and here are the most common:

Allergies (food, environmental, seasonal)

When trying to differentiate and isolate the potential cause of chronic ear infections in your dog, first determine if there is a pattern. For example, if your dog typically develops ear infections in the spring and fall, seasonal allergies or allergic dermatitis may be the cause. If your dog's chronic ear infections do not follow a pattern and occur throughout the entire year then you should investigate potential food allergies or environmental allergies (dust, spores, etc.) as the cause.

The age of the dog when the first ear infection is noticed is also very helpful. Typically, puppies that develop an ear infection are more likely to have a food allergy compared to seasonal allergies. For young dogs (1-3 years of age) when they have their first instance of an ear infection, seasonal or environmental allergies are likely the cause. For older dogs, your veterinarian should perform a detailed physical exam to identify any potential masses or growths that would be present in the ear canal and if there is any evidence of system diseases.

Foreign material (grass, dirt, and debris)

Any foreign material inserted into the ear canal can quickly lead to an ear infection. These act as a source of chronic inflammation in the ear canals that result in the overgrowth of yeast and bacteria.

Parasitic causes

Ear mites and Demodex mites can cause ear infections and should be investigated in young puppies with recurring, chronic ear infections. Especially if the ears are incredibly itchy.

Ear canal masses and polyps

As your dog ages, he/she may develop tumors or growths within the ear canal. These masses are typically benign but can cause chronic irritation and inflammation that lead to infections. Using an otoscope, your veterinarian will be able to visualize the entire ear canal when will reveal a growth if present.

Frequent ear cleaning and plucking of hair within the ear canal(s)

When you frequently clean your dog's ears or pluck fur from their ears, this also increases the risk of developing an ear infection. Plucking hair from the ear canal incites inflammation which will result in an ear infection. Frequent, aggressive cleaning will disrupt the pH and normal ecosystem within the ear canals which will cause an overgrowth of yeast and bacteria, therefore resulting in chronic ear infections.

Immune system suppression (diabetes, Cushing's disease, hypothyroidism)

If your dog has an immune system that is unable to fight off infections, they are at risk of recurrent ear infections. Some conditions such as hypothyroidism and Cushing's disease may cause a dog's immune system to become compromised which will allow for the growth of yeast and bacteria in the ear canals leading to chronic ear infections.

Increased environmental temperature and humidity

When the temperature of the ears is increased there is a global increase in metabolic activity resulting in an overgrowth of yeast and bacteria which will lead to chronic infections. Humidity will also result in swelling of the ear canals, therefore reducing the amount of oxygen entering which promotes the overgrowth of yeast.

Resistant bacteria

Certain types of bacteria, such as Pseudomonas spp. are not susceptible to common ear medications and can result in chronic ear infections in dogs. The ears of dogs with Pseudomonas infections are often severely inflamed and very painful. Pseudomonas infections often require special ear cleaners and medication to help treat them.

What are the common symptoms of chronic ear infections in dogs?

Typical clinical symptoms would include:

  • Head shaking and head tilt
  • Pain and discomfort
  • A foul odor emits from the ears
  • Rubbing or pawing at the ears
  • Aural hematoma (Blood accumulation in the ear pinnae (ear flap))
  • Discharge from the ear canals

How are chronic ear infections in dogs diagnosed?

Your veterinarian will start by taking a detailed history and performing a thorough physical exam including an otoscopic examination of the ear canals. The otoscope can identify any masses, polyps, or growths within the ear canal. Your veterinarian will then take a swab of the ear canals to perform an in-house cytological evaluation that will identify the type of ear infection such as yeast, bacteria, or ear mites.

Culture and sensitivity of the discharge (ear swab)

This is done by taking a sample of the discharge from your dog's ear canals which will be sent off to a veterinary laboratory where they will use a culture medium to determine which bacteria and yeast are present in the ear canal. This test is very important for this diagnosis of chronic ear infections because it can also identify if your dog has a resistant bacterial infection such as Pseudomonas spp. This test is especially useful as the lab will report back which medications will target the specific bacteria that were isolated.

What are the treatment options for chronic ear infections in dogs?

In some dogs, chronic ear infections cannot be cured and the goal of therapy is to reduce flare-ups as much as possible. For example, for dogs with chronic ear infections caused by allergies, the goal would be to manage the allergies as much as possible in order to reduce secondary infection occurrences.

Treating chronic ear infections in dogs is much different than treating an acute ear infection. Yes, both require initial medication to treat, but to be successful the underlying disease or cause needs to be isolated and managed.

Allergies (food, environmental, seasonal)

Talk with your veterinarian about anti-allergy therapy for your dog. If the chronic ear infections are non-seasonal then consider switching your dog's food to a hypoallergenic one. Controlling indoor humidity and having a HEPA filter installed is beneficial. The use of a topical anti-inflammatory (such as hydrocortisone) every couple of days to help as it will reduce the inflammation caused by the allergies.

Foreign material (grass, dirt, and debris)

If these are noticed and suspected, your veterinarian will likely perform an ear flush to retrieve any foreign material present. This procedure is often performed under sedation.

Parasitic causes

If ear mites or Demodex are found, your veterinarian will prescribe the appropriate medication. Ear mite eggs can survive in the environment and can be a source of recurring infection. Therefore, proper environmental control is necessary.

Ear canal masses and polyps

Surgical removal is often necessary. If the mass is large and aggressive, your veterinarian may recommend a total ear canal ablation (TECA) procedure where the entire ear canal is removed.

Chronic ear infections in dogs can be caused by a variety of reasons, the most common being allergies. However, they can also be caused by foreign material such as grass or dirt, parasitic causes such as ear mites, ear canal masses and polyps. If your dog is suffering from chronic ear infections, it is important to take them to your veterinarian so that they can perform an otoscopic examination and determine the underlying cause. Treatment options will vary depending on the cause but may include anti-allergy therapy, treatment for parasites, and surgical removal of masses or polyps.