01 Ear Infection (Otitis Externa)

Infection of the outer ear canal is the most common reason dogs shake their heads repeatedly. These infections are usually bacterial, yeast-based (Malassezia is the most frequent culprit), or a combination of both. They're often triggered or worsened by underlying allergies, moisture in the ear, or the anatomy of the ear canal itself.

Signs alongside head shaking include redness and swelling inside the ear, an unpleasant smell, discharge that may be yellow, brown, or black, and obvious discomfort when the ear is touched. Ear infections need veterinary diagnosis and appropriate treatment — the type of treatment depends on the specific organism involved, and using the wrong product can make things worse.

02 Ear Mites

Ear mites (Otodectes cynotis) are more commonly associated with cats, but dogs can pick them up too — especially those that spend time around cats or other animals. They cause intense itching and produce a distinctive dark, dry, crumbly discharge that's often described as resembling coffee grounds.

Ear mites need specific treatment; they won't clear up on their own. Your vet can confirm the diagnosis and recommend an appropriate product.

03 Grass Seed or Foreign Body

This is particularly common in summer and autumn. Grass seeds — especially the arrow-shaped seeds from meadow grasses — can enter the ear canal during walks through long grass. They're barbed in a way that allows them to travel inward but not back out. Once in the canal, they cause immediate, intense discomfort and rapid inflammation. Left untreated, a grass seed can penetrate deeper into the tissue and cause serious infection or structural damage.

04 Water in the Ear

Swimming and bathing can leave water trapped in the ear canal, which often triggers head shaking as the dog tries to clear it. This is usually temporary and resolves on its own. However, moisture remaining in the ear canal creates conditions that favour infection — so dogs that swim frequently are at higher risk of developing ear infections over time. Ask your vet about safe ways to manage this if it's a recurring issue.

05 Allergies

Environmental allergies (atopic dermatitis) and food sensitivities can both cause inflammation in the ear canal, making it red, itchy, and prone to secondary infection. In dogs with allergies, ear problems often recur because the underlying cause hasn't been addressed. If your dog gets repeated ear infections, allergies are worth investigating with your vet — treating only the infection without addressing the allergy usually means the problem keeps coming back.

06 Wax Build-Up

Some dogs produce more ear wax than others, and in breeds with narrow or very hairy ear canals, wax can accumulate and cause irritation. Mild wax build-up may be managed with regular, appropriate ear cleaning — but your vet should guide you on how and how often. Cleaning too frequently, or using the wrong products, can disrupt the natural environment of the ear and cause more problems than it solves.

07 Polyps or Growths

Growths inside the ear canal — including inflammatory polyps and, less commonly, tumours — can cause persistent head shaking, discharge, and discomfort. These are more common in older dogs and need veterinary assessment. Your vet may recommend examination under sedation or imaging to get a clear picture of what's inside the canal.

08 Vestibular Disease

Vestibular disease affects the balance system and can cause head tilting, shaking, loss of coordination, and rapid involuntary eye movement (nystagmus). It can appear suddenly and look alarming — some dogs fall over or seem unable to stand. It's more common in older dogs and can be caused by middle or inner ear infections, but sometimes no obvious cause is found.