DOGS · Symptom guide
Dog scratching ears and shaking head: what real cases show
Constant ear scratching and head shaking is one of the most common reasons dogs end up at the vet — otitis externa (ear inflammation/infection) is the second-most-prevalent diagnosis in UK primary-care dogs. Most owners think of an ear infection as a one-off event. In reality, repeat ear problems are almost always a downstream sign of something else — usually allergy.
Published cases consistently identify: yeast (Malassezia) overgrowth, bacterial otitis (cocci or, more difficultly, Pseudomonas), ear mites (Otodectes — actually much more common in cats but seen in puppies), foreign bodies (grass awns are a classic in working breeds), aural haematomas from violent head shaking, and underlying atopic dermatitis or food allergy driving the whole cycle.
The cases below show real veterinary workups of dogs presenting with ear scratching and what the cytology, otoscopy, and follow-up actually revealed.
When to see a vet now
- Sudden head tilt or loss of balance — possible middle/inner ear involvement, urgent.
- Painful swelling of the ear flap (aural haematoma) — needs same-week vet attention.
- Bleeding, discharge, or strong foul odour from the canal.
- Recurrence within weeks of finishing drops — almost always means an underlying allergy isn't being addressed.
- Refusal to let you touch the head, hiding, sudden aggression — these are pain signals.
Real cases from the veterinary literature
A teaser of peer-reviewed reports our semantic search surfaces for this complaint. Click into any case for the full abstract — or run a personalised search with your pet's exact details.
- The Inhibitory Effects of Zinc Oxide Nanoparticles on Clinical Isolates of Malassezia in Dogs.
Veterinary medicine and science · 2026
A study found that zinc oxide nanoparticles can effectively fight a common skin yeast called Malassezia pachydermatis, which often causes skin infections and ear problems in dogs. The researchers tested different concentrations of these nanoparticles and discovered that they could inhibit the yeast's growth at very low levels. This could be a promising alternative to traditiona
- Prevalence of ear disease in small-breed dogs undergoing cone-beam computed tomography for dental procedures.
Frontiers in veterinary science · 2026 · United States
A study found that nearly half of small-breed dogs undergoing dental procedures had ear disease, even though many cases were previously undiagnosed. Out of 352 dogs evaluated, 151 were found to have issues, mostly in the external ear canal, with some also having middle or inner ear problems. The researchers used advanced imaging technology (cone-beam computed tomography) to spo
- Phylogenetic and Structural Analysis of Miconazole Susceptibility in Malassezia pachydermatis Isolates From Dogs With Otitis Externa.
Veterinary dermatology · 2026 · United States
A group of 11 dogs with ear infections caused by yeast (Malassezia pachydermatis) were treated with miconazole, a common antifungal medication, but some did not improve. Researchers found that certain genetic changes in the yeast made it less susceptible to miconazole, indicating that resistance is becoming a problem. They noted that while some mutations did not affect how the
- Genomic insights into multidrug resistance and virulence of methicillin-resistantfrom companion animal otitis.
Frontiers in veterinary science · 2026
A study found that 11 strains of methicillin-resistant Staphylococcus (a type of bacteria) were linked to ear infections (otitis externa) in dogs and cats. These strains showed resistance to multiple antibiotics, making treatment challenging. The researchers used advanced genetic testing to understand the bacteria better and discovered that many of these strains could cause ser
- Incidence Rate of Otitis Externa Episodes in Atopic Dogs Is Reduced by a Therapeutic Diet in a 6-Month Randomised, Blinded, Controlled, Clinical Trial.
Veterinary dermatology · 2026 · France
A group of 34 dogs with itchy skin and ear infections were given either a special therapeutic diet or a regular diet for six months. The dogs on the therapeutic diet had significantly fewer ear infections compared to those on the regular diet, with only 25% experiencing infections versus 61% in the control group. Both groups showed some improvement in their skin condition, but
- A novel approach to treating canine otitis externa with medical ozone: A comparative clinical, cytological and microbiological research.
Veterinary journal (London, England : 1997) · 2026
A group of 27 dogs with ear infections (otitis externa) were treated with either ozone therapy, a common antibiotic ear drop, or a veterinary ear solution. The dogs receiving ozone therapy showed complete recovery, with no bacterial growth detected in their ears, while only a third of those treated with the antibiotic drops improved. The ozone treatment not only eliminated the
Frequently asked questions
- Why do my dog's ear infections keep coming back?
- Almost always because the underlying cause hasn't been addressed. The most common driver is allergy — atopic dermatitis or food allergy. Until the allergy is managed, the ear environment stays primed for repeat infections. If your dog has had ≥3 ear infections in a year, ask your vet about allergy workup or a strict food trial.
- Can I just use a cleaner from the pet shop?
- For routine maintenance in healthy ears, yes. But once there's an active infection, the eardrum status must be confirmed first — many topical antibiotics can damage the inner ear if the eardrum is ruptured. Vinegar, hydrogen peroxide, and other home remedies can worsen inflammation. Get a cytology before starting anything medicated.
- What's the worst-case scenario?
- Pseudomonas otitis is the toughest infection in primary practice — it forms biofilms, develops resistance fast, and can rupture the eardrum if mismanaged. Untreated chronic disease leads to ear-canal scarring and end-stage otitis, sometimes requiring total ear canal ablation (TECA) surgery. Don't ignore chronic ear problems — early aggressive management protects long-term hearing and comfort.