Why Water Isn’t Always the Cause of Your Dog’s Swimmer’s Ear

blog image
Based on an article that first appeared at

In veterinary medicine, not all conditions are as simple as the name might suggest. One of the best examples of this is the condition of swimmer’s ear. While you may recognize that as a type of ear infection us humans can get, it’s also a term you might hear at the veterinary office, especially if your dog is displaying symptoms of head shaking, pawing or rubbing at the ears, ear twitching, or even vocalizations like whining or crying. 

But despite the name being shared between dogs and humans, there are some differences that can result in confusion for many pet owners. In fact, a client and I recently chatted about how so many dogs in her walking group get ear infections in the summer. While some of the dogs swam, most of them didn’t. So, she wondered why they were all getting “swimmer’s ear.”

In this blog, I’ll be demystifying swimmer’s ear in dogs and talking about some common factors that can lead to dog ear infections both in and out of the water. 

The Name Swimmer’s Ear May Be a Little Misleading

For starters, let’s address how veterinarians and owners talk about swimmer’s ear in dogs. While the name may lead you to believe the cause and diagnosis is simple and straightforward, the name is actually a little misleading. In fact, the way we refer to certain ailments, like ear infections or swimmer’s ear might not be the most appropriate or accurate for every dog’s situation. Namely, I feel that “ear infection” is one of the most inappropriately used terms by veterinarians — myself included. 

When people hear “ear infection,” they will typically think about inner ear infections or infections that are inside the eardrum, like the ones that little kids might get. While we do see these infections in dogs, it’s pretty rare. A more appropriate term for us to use would be “skin infection of the ear canal,” also known medically as otitis externa. In humans, water trapped within the ear after swimming or being exposed to water is the most common cause. However, dogs — unlike us — shake the bejeezus out of their heads after swimming, typically removing it all and leaving little chance for infection to develop. So, if it’s unlikely that water is trapped to a degree where infections can occur, then what’s the cause? In numerous cases that I see in the clinic the real cause of ear infections and swimmer’s ear-like symptoms is actually allergies.  

A small dog scratching an itchy ear affected by allergies.

How Allergies Can Affect Your Dog’s Ears

For dogs, anatomy plays a large role in the development of ear infections, as the construction of a dog’s ear canal can contribute to an increased likelihood in the spread of infection causing bacteria and yeast. A dog’s ear canal is four to six times the length of a human’s; it is essentially a long tunnel of skin with a 90 degree bend halfway in, meaning there’s a lot of surface area for bacteria to grow. 

Normally, the skin within a dog’s ear canal is healthy and intact and acts as a barrier between germs and the meaty tissue just underneath it. On other parts of the body, trauma to the skin can allow these organisms to get into that deeper tissue and spread, causing infection. This infection is often uncomfortable for dogs and causes them to chew and scratch the area around the infections until it inevitably becomes a “hot spot.” 

The ears are no different. Unless they were recently cleaned, the surface of the ear canals always has a layer of bacteria and yeast sitting on it. All they need is a little damage to that skin and the ear canal becomes infected. As I’ve discussed in the past, allergies don’t just cause rubbing of the eyes and nose like they do in people — they can lead to a number of uncomfortable or painful symptoms that can manifest all over a dog’s body and the ears are no exception. Allergens can also get into the skin of dogs and stimulate the brain to tell them to scratch and rub, leading to hot spots. In the case of the ears, the closed, warm environment makes this a perfect incubator, and the infected skin within is much worse off. 

Don’t Count Water Out as a Cause of Ear Infections Just Yet

While allergies are the most common cause of ear irritation that I see, that doesn’t mean that dogs can’t still get infections from swimming and exposure to bacteria in bodies of water. Enclosed waterways near housing in developed or urban areas tend to have higher bacterial counts. Bacterial density in bodies of water can be worse after rainstorms when older septic systems and public sewer overflow releases effluent into the water and cause direct infections. Avoiding these types of beaches and bodies of water, especially after storms, is one way to reduce the risk of ear issues in your canine companions. 

Another is to reduce or eliminate the water from the ear. Since the ear canals are so long, simply wiping your dog’s ears after swimming or bathing is not enough. Veterinarians carry special ear flushes that are safe to use and will not cause inner ear damage, as opposed to other products or drying instruments. Instilling these special washes into the ear work by displacing the dirty water and encouraging drying, decreasing the likelihood of bacterial growth and spread.

Veterinarians examining a dog's ear.

Prevention Is the Best Medicine for Dog Ear Infections 

While these outer ear infections are not as nasty as inner ear infections, we still take them very seriously. There is always a possibility that these infections can spread into the deeper ear causing damage or deafness. Additionally, it’s important for dog owners to know that even treated infections can lead to scar tissue buildup over time when infections are recurrent. This buildup can be so bad that the ear canal may eventually require surgical removal. To avoid these cases, prevention is the best course of action. Preventing ear infections with a good anti-allergy regimen and regular cleaning is crucial to keeping your dog’s ear functional and pain-free. 

If you suspect your dog is experiencing any pain or discomfort in their ears, be sure to get in touch with your veterinarian. Working with your vet early on can minimize the discomfort your precious pup feels and mitigate any unnecessary or long term damage to your dog’s hearing. 

If you have questions and you'd like to reach out to us, you can call us directly at (201) 350-1802, or you can email us at [email protected]. Don't forget to follow us on social media Facebook, Instagram.