Every July we see the same pattern at the salon: a dog comes in for a groom, and somewhere in the middle of the appointment we notice them tilting their head, or we catch a whiff of something off when we lift an ear flap. Nine times out of ten, the owner mentions a weekend at the lake, a few laps in the backyard pool, or an afternoon wading in a creek off the Katy Trail. The swimming was the fun part. The ear infection is what showed up three days later.
This is one of the most common and most preventable issues we see in summer, and it rarely gets the attention that matting or sunburn does. So here's what's actually happening inside your dog's ears when they get wet — and the routine that keeps it from turning into a vet visit.
Why Swimming Leads to Ear Infections
A dog's ear canal isn't a straight shot like ours. It runs vertically down from the opening, then takes a turn and runs horizontally toward the eardrum. That bend is exactly where water likes to sit. Once water gets trapped down in that canal, it doesn't drain back out on its own — and a warm, dark, damp ear canal is close to ideal conditions for bacteria and yeast that are normally present in small numbers to multiply out of control. According to the American Kennel Club, that overgrowth can start taking hold within about 24 to 48 hours of water getting trapped in the ear — which is why a dog who swam fine on Saturday can be head-shaking and miserable by Monday.
Vets call this condition otitis externa — inflammation of the outer ear canal — and it's one of the most common ear problems dogs deal with. Swimming isn't the only cause, but it's a major one, and it's the one we see spike every summer as soon as the lakes and pools open up.
Which dogs are most at risk?
Any dog who swims regularly can develop an ear infection, but a few things stack the odds:
- Floppy, low-set ears: Labs, Goldens, Cocker Spaniels, and most Doodles have ear flaps that sit down over the canal opening, which cuts off airflow and traps humidity against the ear.
- Hairy ear canals: Poodles, Doodles, and Schnauzers often grow hair down inside the canal itself, which holds moisture against the skin even after the outside of the ear looks dry.
- Frequent or repeated swimming: One swim and a good dry-off is usually fine. It's the dog who's in and out of the water all weekend, with ears that never fully dry between dips, who ends up at risk.
Belle, one of our own dogs, is a Weimaraner with ears that hang low and stay damp longer than you'd think just from a splash in a kiddie pool — so we're doing the same drying routine on her that we're about to walk you through.
How to Dry Your Dog's Ears After Swimming
The single most useful habit you can build is drying ears every time your dog gets in the water — not just after a bath, but after the lake, the pool, the creek, even a long session with the sprinkler.
- Use a soft, dry towel or cotton cloth to gently wipe out the visible part of the ear canal and the underside of the ear flap. Don't push the towel down into the canal — just reach as far as your finger comfortably goes.
- Follow with a veterinary ear-drying solution if your dog swims often. These are formulated to evaporate excess moisture out of the canal rather than just sitting there, and most pet supply stores carry one.
- Never use cotton swabs, hydrogen peroxide, or rubbing alcohol in a dog's ear. Swabs can pack debris deeper into the canal instead of removing it, and peroxide and alcohol can irritate already-sensitive skin. This one's worth remembering — it's the AKC's top warning on ear care, and it's a mistake we still see well-meaning owners make.
- Let air get to the ears when you can. If your dog has heavy ear fur, keeping the hair around the ear opening trimmed short helps the canal actually dry instead of staying sealed under a mat of wet fur.
Should I clean my dog's ears every time they swim?
Drying, yes, every time. A deeper cleaning with a pH-balanced ear cleaner is a different routine — once a week is plenty for a dog who swims regularly, and more than that can actually irritate the canal and make things worse. If you're not sure how often is right for your dog's ears, that's exactly the kind of thing to ask us at your next appointment.
Signs of an Ear Infection to Watch For
Even with a good drying routine, it's worth knowing what an ear infection looks like so you can catch it early:
- Head shaking or tilting that doesn't stop after a normal shake-off
- Scratching at one ear more than the other
- A noticeable odor coming from the ear
- Redness, swelling, or visible discharge inside the ear
- Sensitivity or flinching when the ear is touched
We are groomers, not veterinarians, so we don't diagnose or treat ear infections — but if you notice any of these signs, it's worth a same-week vet visit rather than waiting it out. Ear infections that go untreated tend to get more painful and more expensive to resolve the longer they sit.
What We Check at Every Groom
Ear care is a standard part of every groom at American Puppy, not an add-on. We check inside each ear for wax buildup, odor, redness, or anything that looks off, and we trim excess ear hair on breeds who need it so air can actually reach the canal. If we notice something that looks like it's heading toward an infection, we will tell you — the same way we would flag a lump or a hot spot — so you can get ahead of it before your dog is uncomfortable. We cover a few of the other early-warning signs we watch for in our guide to knowing when your dog is overdue for a groom.
Missouri Summers Make This Worse
Between Lake St. Louis, the pools that open up across St. Charles County, and the sheer number of dogs who end up in a creek on a Katy Trail walk, this area gives dogs a lot of chances to get water in their ears every single week of summer. Add in our humidity — which slows down how fast anything actually dries, ears included — and you've got the exact conditions that let a normal swim turn into a Monday-morning vet appointment. We talk more about how our humidity affects grooming and coat care generally in our Missouri summer grooming guide, and the same principle applies here: wet plus warm plus no airflow is trouble, whether it's a coat or an ear canal.
None of this means keeping your dog out of the water — swimming is good exercise and most dogs love it. It just means building the thirty-second ear check into your after-swim routine the same way you'd towel off their coat. Ready for us to take a look at your dog's ears as part of their next groom? Book an appointment and we will check things over while we're at it.
Frequently Asked Questions
How do I know if my dog has an ear infection from swimming?
Watch for head shaking or tilting, scratching at one ear, a noticeable odor, redness or discharge inside the ear, or sensitivity when the ear is touched. These can show up within a day or two of swimming. If you notice any of these signs, see your veterinarian — grooming can help prevent ear infections, but diagnosing and treating one is a job for the vet.
How do I dry my dog's ears after swimming?
Gently wipe the visible part of the ear canal and underside of the ear flap with a soft, dry towel after every swim. For dogs who swim often, follow up with a veterinary ear-drying solution, which is made to evaporate moisture out of the canal. Never use cotton swabs, hydrogen peroxide, or rubbing alcohol in a dog's ear.
Which dog breeds are most prone to ear infections from swimming?
Breeds with floppy, low-set ears — Labs, Goldens, Cocker Spaniels, and most Doodle mixes — are at higher risk because their ear flaps trap humidity against the canal. Breeds with hairy ear canals, like Poodles and Schnauzers, are also more prone, since the hair holds moisture against the skin even after the outer ear looks dry.
How often should a dog's ears be professionally cleaned in summer?
For a dog who swims regularly, a weekly at-home ear check plus a deeper clean is reasonable, but every dog is different — over-cleaning can irritate the canal. Ear checks are part of every groom at American Puppy, so if your dog is on a normal grooming schedule, that's a built-in checkpoint on top of what you're doing at home.
Is it safe to let my dog swim in Missouri lakes and rivers this summer?
Yes — swimming is great exercise and most dogs love it. The key is pairing it with a quick ear-drying habit afterward. A dog who swims often and gets dried off every time is in a very different position than one whose ears stay damp for days at a stretch.
Can I use a cotton swab to clean my dog's ears?
No. Cotton swabs can pack wax and debris deeper into the ear canal instead of removing them, and they risk injuring the eardrum if a dog moves suddenly. Stick to wiping the outer canal with a soft cloth or using a vet-approved ear cleaner designed for dogs.