The most common reason a dog repeatedly shakes his head is an ear problem, usually an infection or irritation inside the ear canal. Occasional head shaking is normal, but if your dog is doing it multiple times a day or pawing at his ears alongside the shaking, something is bothering him. The L-shaped structure of a dog’s ear canal makes it a natural trap for moisture, wax, and debris, creating the perfect environment for bacteria and yeast to grow.
How a Dog’s Ear Canal Creates Problems
Unlike the human ear canal, which runs mostly horizontally, a dog’s ear canal is shaped like a capital L. The long portion of that L points upward, which means any fluid, wax, or debris that gets inside tends to stay there rather than draining out on its own. Water from baths or swimming pools, normal skin oils, and shed skin cells can all pool at the bottom of that canal. Once moisture and organic material accumulate, bacteria and yeast have an ideal place to multiply.
This anatomy is the reason ear problems are so common in dogs. About 7.3% of dogs in the UK are diagnosed with an outer ear infection in any given year, and the true number is likely higher since many mild cases go unnoticed for a while.
Ear Infections: The Most Likely Cause
Bacterial and yeast infections of the outer ear canal are by far the most frequent reason for persistent head shaking. The bacteria most often involved are Staphylococcus species, though Pseudomonas and several others can play a role. A yeast called Malassezia is also extremely common. Many infections involve both bacteria and yeast at the same time.
You can sometimes get clues about what type of infection your dog has by looking at the discharge. Yeast infections typically produce a brown, waxy discharge with a noticeable musty or sour odor, along with redness and itching. Bacterial infections may produce yellow or greenish discharge and can smell even worse. Both types cause head shaking, ear scratching, and visible discomfort when you touch the ear.
If an outer ear infection goes untreated, it can spread deeper into the middle or inner ear. Inner ear infections are harder to resolve and can cause hearing loss or lasting balance problems, so catching things early matters.
Ear Mites and Parasites
Ear mites (Otodectes cynotis) are tiny parasites that live inside the ear canal and feed on skin oils and wax. They’re more common in puppies and dogs that spend time around cats, which are frequent carriers. The hallmark sign is a dark, crumbly discharge that looks like coffee grounds. If you see that texture in your dog’s ears alongside intense head shaking and scratching, mites are a strong possibility. Mites are highly contagious between animals, so other pets in the household may need treatment too.
Foreign Objects in the Ear
A sudden onset of violent, nonstop head shaking, especially after time outdoors, often points to something stuck in the ear canal. Foxtail grass seeds are a common culprit in many parts of the country. These barbed seeds can work their way deep into the canal and won’t come out on their own. Your dog may tilt his head to one side and shake frantically, sometimes yelping. This situation needs professional removal since pushing the object deeper can damage the eardrum.
Breeds at Higher Risk
Some dogs are simply built in a way that makes ear trouble more likely. A large UK study found that Basset Hounds had nearly six times the odds of developing an outer ear infection compared to mixed-breed dogs. Chinese Shar Peis had about 3.4 times the risk, Labradoodles nearly three times, Beagles 2.5 times, and Golden Retrievers about 2.2 times.
The pattern is largely about ear shape. Dogs with pendulous, floppy ears had roughly 1.8 times the odds of infection compared to dogs with erect ears. Floppy ears cover the canal opening, reducing airflow and trapping warmth and moisture inside. Poodle-type breeds also showed higher risk (about 1.9 times), likely because their curly hair grows inside the ear canal and further blocks ventilation. On the other end, Chihuahuas, Border Collies, Yorkshire Terriers, and Jack Russell Terriers all had lower-than-average risk.
If you own a floppy-eared or curly-coated breed, regular ear checks are especially important.
Allergies as an Underlying Trigger
Allergies are one of the most overlooked reasons for recurring ear infections. Dogs with environmental allergies (pollen, dust mites, mold) or food sensitivities often develop inflamed ear canals as part of their allergic response. The inflammation changes the canal’s environment, making it easier for bacteria and yeast to take hold. If your dog gets ear infections repeatedly, especially at the same time each year or alongside itchy skin and paw licking, allergies may be the root cause rather than the ears themselves.
When Head Shaking Means Something More Serious
Most head shaking traces back to the outer ear, but there are times when it signals a deeper problem. Vestibular disease, which affects the balance system in the inner ear or brain, causes a persistent head tilt (not just shaking) along with stumbling, circling, falling to one side, or rapid involuntary eye movements. The onset is often sudden and dramatic. If your dog is losing coordination or seems disoriented alongside head tilting, that points to a vestibular issue rather than a simple ear infection and warrants prompt veterinary attention.
Aural Hematomas From Too Much Shaking
Vigorous, repeated head shaking can cause a secondary problem: an aural hematoma. This happens when blood vessels inside the ear flap rupture from the force of shaking, and blood collects between the skin and cartilage. The ear flap swells up like a pillow or balloon and feels warm, fluid-filled, and puffy. In the early stages it may be tender to the touch. Hematomas don’t resolve well on their own. Small ones can sometimes be drained and treated with medication, but larger ones often need a surgical procedure to prevent the ear flap from scarring into a permanently crumpled shape. The best way to prevent a hematoma is to address whatever is causing the head shaking in the first place.
How to Safely Clean Your Dog’s Ears
Regular cleaning can help prevent buildup that leads to infections, especially for high-risk breeds. Cornell University’s veterinary college recommends filling the ear canal with a veterinary ear cleaning solution, then gently massaging the base of the ear for several seconds to loosen debris. Your dog will want to shake his head after this, which actually helps bring loosened material up and out of the canal.
After the shake, use cotton pads or cotton balls to wipe away debris. Only go as far into the canal as your finger comfortably fits, roughly one knuckle deep. A few important warnings: never use cotton swabs, which can push debris deeper or injure the eardrum. Don’t force cleaning solution in under pressure, as that can rupture the eardrum. And avoid anything containing alcohol or hydrogen peroxide, both of which can irritate the delicate skin lining the canal.
If your dog’s ears are already red, swollen, painful, or producing discharge, skip the home cleaning. Putting anything into an already-infected ear without knowing whether the eardrum is intact can cause permanent damage. That’s a situation where your dog needs an exam first so the right treatment can be matched to whatever is actually going on inside the canal.