Health & Diseases

Bloody Ears in Dogs: Recognizing and Treating Otematoma & Recurrences

An aural hematoma (blood ear, otohematoma) is an accumulation of blood between the cartilage and skin of a dog's pinna. It occurs due to the rupture of small blood vessels in the pinna tissue—usually as a result of vigorous head shaking or scratching. The result is a tense, elastic, fluctuating swelling on the inside of the pinna.

Bloody Ears in Dogs: Recognizing and Treating Othematoma & Recurrences

What is a blood ear in dogs?

An ear hematoma (otematoma, aural hematoma) is a collection of blood between the cartilage and skin of a dog’s outer ear. It is caused by the rupture of small blood vessels in the outer ear tissue—usually as a result of vigorous head shaking or scratching. The result is a firm, elastic, fluctuant swelling on the inner side of the outer ear.

Ear hematomas almost never occur spontaneously—they are almost always a consequence of another condition that causes the dog to shake or scratch its ear: otitis externa, ear mites, atopy, or a foreign object in the ear canal. A bloody ear is therefore a symptom, not a problem in and of itself.

Background + Scientific Context

Fossum (2018, *Small Animal Surgery*) describes the pathogenesis and treatment methods: The otematoma is caused by trauma—shear forces generated by head shaking rupture blood vessels in the perichondrium. The accumulated blood partially coagulates and partially lyses—the contents are a mixture of fresh blood, clots, and serous effusion. If left untreated: fibrotic reaction with scar contraction → cauliflower ear. Standard treatment: surgical drainage with fixation of the perichondrial skin layers using a drain and sutures.

Kuwahara (1986, American Journal of Veterinary Research, https://pubmed.ncbi.nlm.nih.gov/3777654/) described clinical and experimental observations of hematomas in dogs and cats: Histologically, early lesions show blood extravasation between the perichondrium and cartilage; later stages show granulomatous inflammation and fibrotic organization. The immune complex hypothesis (autoimmune component) was discussed—the traumatic origin is clearly established. Recurrence rate after aspiration alone: 50–90%.

Zur and Lifshitz (2016, Veterinary Dermatology, https://pubmed.ncbi.nlm.nih.gov/27029856/) evaluated 77 dogs with otematoma: The most common underlying causes were otitis externa (67%) and atopy (24%). With consistent treatment of the underlying cause, the recurrence rate decreased significantly. Conservative treatment with oral corticosteroids resulted in complete resolution in 50–60% of cases; surgical drainage was indicated when conservative therapy failed.

Vitomalia-Position

An ear infection is painful, continues to worsen without treatment, and can cause permanent deformities if fibrosis sets in. No home remedy can replace veterinary drainage—but more importantly, the underlying cause (otitis, mites, atopy) must be treated at the same time. Otherwise, another ear infection is inevitable.

When does the blood ear become relevant?

  • A soft, fluctuating swelling on the inside of the ear
  • The dog shakes its head or scratches its ear vigorously
  • Swelling on one or both sides of the outer ear
  • Known cases of otitis externa, atopy, or ear mite infestation
  • Swelling increases within hours to days

Practical application

A comparison of treatment options:

Method Procedure success rate Disadvantages
Aspiration (needle) Remove blood, no occlusion Low (recurrence rate 50–90%) Often a short-term solution
Conservative (Oral corticosteroids) Anti-inflammatory effect, resorption 50–60% for small hematomas Time-consuming; not suitable for large hematomas
Surgical Drainage Incision, drainage, suture closure High (approx. 80–90%) Anesthesia, follow-up care required
Intralesional injection Cortisone injected directly into the hematoma Moderate Less standardized

Postoperative care following surgical drainage: - E-collar for 2–3 weeks — no scratching, no head shaking - Regular wound checks; sutures removed after 10–14 days - Simultaneous treatment of the underlying cause (otitis externa: ear drops/systemic therapy; ear mites: antiparasitic agents; atopy: allergy evaluation)

Common underlying causes: - Otitis externa (bacteria, yeast): the most common cause - Ear mites (Otodectes cynotis): especially in young dogs and households with multiple dogs - Atopic dermatitis: chronic itching → recurrent - Foreign bodies (barnyard grass seeds): seasonal, acute

Common Mistakes & Myths

  • “A blood blister will go away on its own.” Small hematomas can resolve spontaneously—but are highly likely to result in permanent fibrosis and deformation of the outer ear. Without treatment, cauliflower ear (scar contracture) is the common outcome.
  • “Aspiration with a syringe is sufficient.” Simple aspiration without securing the tissue layers leads to recurrence in over 50% of cases. Surgical drainage with suture fixation is the treatment recommended by clinical guidelines.
  • “The ear infection is the real problem.” No—the ear infection is a symptom of another problem. Without treating the underlying cause (otitis, allergies, mites), the cycle will repeat itself.

Current State of Research (2026)

Ear hematomas in dogs are well characterized. Current debate centers on the optimal treatment approach for small versus large hematomas and the value of intralesional corticosteroid injections as a minimally invasive option. Consensus: surgical drainage with suture fixation remains the gold standard for large and persistent hematomas. Prevention through consistent treatment of otitis externa and atopy is effective.

Frequently Asked Questions

What is an ear infection in dogs, and how does it develop?

A blood blister (hematoma) is a collection of blood between the cartilage and the skin of the outer ear. It occurs when small blood vessels rupture due to head shaking or scratching—usually caused by an ear infection, ear mites, or allergies.

Can I treat my dog's ear infection at home?

No—without professional drainage and treatment of the underlying cause, the condition will recur and leave permanent scarring. You should see a veterinarian as soon as possible. Attempting to treat the condition yourself with needles increases the risk of infection.

Does an ear infection in dogs go away on its own?

Small hematomas may resolve on their own, but they often leave behind fibrosis and deformity of the outer ear (cauliflower ear). Veterinary treatment speeds up healing and minimizes long-term damage. Without treating the underlying cause, a relapse almost always occurs.

Related terms

Sources & Further Reading

  1. Fossum, T. W. (Ed.) (2018). Small Animal Surgery (5th ed.). Elsevier. ISBN 9780323442558.

  2. Kuwahara, J. (1986). Canine and feline aural hematoma: clinical, experimental, and clinicopathologic observations. American Journal of Veterinary Research, 47(10), 2300–2308. https://pubmed.ncbi.nlm.nih.gov/3777654/

  3. Zur, G., & Lifshitz, B. (2016). Canine aural haematomas: clinical findings and response to treatment in 77 cases. Veterinary Dermatology, 27(3), 188–e48. https://pubmed.ncbi.nlm.nih.gov/27029856/

Wissenschaftliche Einordnung

Fossum (2018, Small Animal Surgery) describes the pathogenesis and treatment methods: Aural hematoma occurs due to trauma — shearing forces during head shaking rupture blood vessels in the perichondrium. The accumulated blood partially clots and partially lyses — the content is a mixture of fresh blood, coagulum, and serous effusion. Untreated: Fibrotic reaction with scar contraction → cauliflower ear. Standard treatment: surgical drainage with drainage/suture fixation of the perichondrium-skin layers.

Kuwahara (1986, American Journal of Veterinary Research, https://pubmed.ncbi.nlm.nih.gov/3777654/) described clinico-experimental observations on aural hematomas in dogs and cats: Histologically, early lesions show blood extravasation between the perichondrium and cartilage; later stages show granulomatous inflammation and fibrotic organization. The immune complex hypothesis (autoimmune component) was discussed — the traumatic genesis is clearly proven. Recurrence rate after aspiration alone: 50–90%.

Zur and Lifshitz (2016, Veterinary Dermatology, https://pubmed.ncbi.nlm.nih.gov/27029856/) evaluated 77 dogs with aural hematoma: The most common underlying causes were otitis externa (67%) and atopy (24%). Consistent treatment of the underlying cause significantly reduced the recurrence rate. Conservative treatment with oral corticosteroids showed complete resolution in 50–60% of cases; surgical drainage was indicated when conservative therapy failed.