Dog Ear Infections: Causes, Symptoms and Treatment
Ear infections, also known as otitis externa, are one of the most common reasons for dogs to visit the vet. They can be very painful, and if left untreated can cause serious disease, deafness, and damage to the inner ear. In many cases, ear infections can be extremely frustrating for owners as they frequently recur time and time again, and over time the cost of repeated vet consultations, testing, and medication can quickly add up.
The good news is that if you team up with your vet to address the underlying causes and predisposing factors involved, you can take control and break the cycle of recurrent ear infections!
- Red skin in and around the ears
- Pain when the ears or head are touched
- Excessive scratching at the ears or shaking the head
- Tilting of the head
- Presence of an odour or discharge in or around the ear
The short answer to this question is, anything that causes inflammation of the ear canal can result in an infection. The ear canal can become inflamed due to seasonal allergies and atopy, parasites, auto-immune disorders, excessive moisture, or food allergies, and this warm, moist environment becomes the perfect breeding ground for yeast and bacteria. The long answer? Ear infections in dogs are caused by a combination of: predisposing factors, underlying causes and opportunistic yeast and bacteria. While yeast and bacteria may be easily killed with a course of antibacterial or antifungal drops, an understanding of the predisposing factors and underlying causes present is essential to prevent the infection from recurring.
Physical and environmental factors can predispose dogs to ear infections
Some dogs are naturally predisposed to getting ear infections, due to the conformation of their ears. Narrow ear canals, excessive fur within the ear, and long floppy ears can all increase your dog's likelihood of ear infections. Breeds that are particularly prone include pugs, cocker spaniels, poodles and poodle mixes like spoodles and labradoodles, bichon frises, beagles, and retrievers.
Skin allergies are a common underlying cause
Dogs with skin issues are also more likely to suffer from ear infections. Why do ear infections and itchy skin go hand in hand? It's no coincidence that ear infections and skin allergies often flare up at the same time. This is because the inside of the ear is really just an extension of the skin. Therefore, anything that irritates the skin will also irritate the skin within the ear canal, which leads to inflammation, heat, and moisture - in other words, the perfect environment for bacteria and yeast to set up camp!
Yeast and bacteria overgrow when the ear is inflamed
There are many different types of microbes that can cause ear infections. All of the common microbes are generally considered 'commensal organisms', which means they are usually found in small amounts on healthy skin. But when conditions are favourable, such as in moist, hot, inflamed skin, they can overgrow and cause infection.
Bugs that can 'set up camp' in your dog's ear and cause infection include:
Malassezia pachydermatis - a commensal species of yeast which lives normally on the skin in small amounts. Malassezia often causes a black ear discharge with a characteristic musty smell and can also play a part in some chronic skin infections. Read more in Yeast Infections in Dogs
Staphylococcus intermedius - a gram-positive cocci (sphere shaped bacteria) which typically causes a more watery, lighter-coloured discharge in the ear. It is also the primary cause of many skin infections.
Pseudomonas aeruginosa - a gram-negative rod-shaped bacteria. This is often present in severe, pus-filled ear infections with yellow or green discharge.
Other less common bacteria, including Streptococcus species, Proteus mirabilis, E. coli and Staphylococcus aureus. These are usually seen in conjunction with one of the other common microbes.
Step 1 - Treat the Infection and Inflammation
The first step is to clear up the current infection. This will usually require 10-14 days of medicated ear drops, prescribed by your vet. Your pet may also be given an anti-inflammatory drug or corticosteroids for some much-needed relief.
A general non-medicated ear cleaner may also be recommended by your vet, to help clear any debris prior to putting the medicated drops in the ear. This non-medicated general ear cleaner can also be used after the infection has cleared, for ongoing ear maintenance. Long term, it is a good idea to clean your dog's ears once per week, and after every time your dog goes swimming or has a bath.
Epi Otic is highly recommended by vets. It removes debris, cerumen and pus from the ear canal and also has a drying agent to remove excess moisture.
Formulated by a veterinary dermatologist, Otoflush helps to remove wax and exudate build up and improves the penetration and effectiveness of prescribed ear medication.
A diagnosis is important to ensure the best treatment
One of the reasons why you should never skip the vet appointment and try to treat at home is because a diagnosis of the type of yeast or bacteria present is needed to choose the right medication. Different pathogens often require different medication which it's no good just buying an ear medication online and hoping for the best.
Your vet will be able to take a swab from deep inside the ear canal and take a look at the cells under a microscope. Usually, they will be able to diagnose the type of microbe in just a few minutes (no need to 'wait for a pathologist' - vets are multi-talented!). However, there may be some instances where your vet prefers to send off a sample for specialist testing, such as when resistance or an unusual pathogen is suspected.
A full examination of the ear canal with an otoscope will also be performed. This will help rule out issues such as ear mites, tumours, or grass seeds. It will also allow your vet to assess whether the ear drum membrane is intact. Many chronic infections can lead to an irritated and fragile membrane which can burst, exposing the structures of the inner ear. It's extra important for your vet to visualise the state of the ear drum, because some ear medication can be toxic if the membrane is not intact. This is another reason why you shouldn't just treat at home without a vet examination!
Once the infection has cleared, underlying causes such as allergies need to be addressed. If the underlying cause isn't treated, the ear infection will probably return.
The gold standard for investigating allergies is to have a intradermal skin and/or blood testing in consultation with a veterinary dermatologist. However, you can rule out some conditions such as food allergies with an hypoallergenic diet trial.
Step 3 - Improve the skin barrier, improve the ears
Even if you aren't sure what your pet is allergic to, or what the underlying cause of their ear infection is, improving the skin barrier can help reduce flare ups of itchy skin as well as ear infections. A stronger skin barrier means that fewer allergen proteins can penetrate the surface of the skin and cause a reaction, it also promotes a quicker healing and repair time.
One of the most effective and natural ways to strengthen the skin barrier is to increase the omega 3 and 6 fatty acids, particularly from marine sources, in the diet. You could swap your pooch over to a skin care diet or a fish-based dog food, or alternatively you can add extra omega fatty acids directly to your pet's usual food with PAW Blackmore's Fish Oil 500 Veterinary Strength
As well as increasing the omega fatty acids in your dog's diet, regular use of moisturising conditioners such as Aloveen Oatmeal Conditioner can also be helpful to provide a physical barrier against allergens and help nourish the skin cells so they are stronger.
Royal Canin Skintropic is formulated to provide nutritional support to dogs with skin disorders like atopic dermatitis, flea allergy dermatitis and pyodermatitis. Dogs weighing <10kg should use Skintopic for Small Breeds.
Paw Blackmore's Fish Oil contains a concentrated blend of liquid fish oil, a rich source of omega fatty acids, EPA and DHA in a formula specifically designed for pets.
Made with soothing oatmeal, this conditioner can be applied to wet or dry fur as a moisturiser to protect the skin barrier. It also smells lovely!
In most cases, ear infections can be avoided by identifying and addressing any underlying causes and predisposing factors. Working with your veterinarian to keep your dog's allergies under control can make a big difference. Try to get into the habit of cleaning your dog's ears regularly, especially after bathing or swimming. Make sure that you ask your vet about how to clean your dog's ears correctly, or see our video How To Safely Clean Your Dog's Ears.
By taking some time to address the underlying causes, you can help to prevent ear infections from recurring and keep everyone happy!
After some more food recommendations? See below for some diets that may help reduce the occurrence of ear problems by supporting skin health.
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