Ear infections in dogs: signs, treatment, and prevention

Otitis is an inflammation of the ear that very commonly affects dogs. It may involve only the external ear canal (the most common form), but it can sometimes extend to the middle or inner ear if left untreated.

Why It’s Important

Otitis is uncomfortable and painful, and it can lead to complications if it becomes chronic or is not treated properly. A ruptured eardrum, persistent pain, balance disorders, or hearing loss may occur and can cause significant issues for your pet.

How to Regularly Inspect Your Dog’s Ears

Once a week, establish a simple ear-inspection routine for your pet:

Check the external appearance: skin color, redness, swelling.
Smell the ears: a foul or unusual odor may indicate the beginning of an infection.
Look for discharge: excessive brown or black discharge may indicate irritation or the presence of parasites.
Monitor behavior: scratching, frequent head shaking, head tilting, or a painful reaction when the ears are touched.

Types of Infections and Common Causes

Otitis can have several underlying causes:

Bacterial or fungal infections: bacteria and yeasts (notably Malassezia) are common causes, especially in humid environments.
Parasites: ear mites can cause intense inflammation, discharge, and excessive scratching.
Allergies: food or environmental allergies cause chronic inflammation, which promotes secondary infections. These flare-ups often occur cyclically at the same times of year.
Foreign bodies: debris or a mass in the ear (such as a polyp) can lead to irritation, infection, and sometimes bleeding.
Other causes: certain breeds are anatomically predisposed (drooping ears or narrow ear canals) and are at higher risk for recurrent otitis.

Preventing Otitis

Ear Care Routine

Clean your dog’s ears using a product specifically formulated for dogs. Cotton swabs should be avoided, as they can push debris deeper into the ear canal or cause injury.
Dry the ears after swimming or exposure to rain, as moisture promotes the growth of bacteria and yeast.
In dogs with long ear hair, regular grooming and hair removal from the ear area help improve air circulation and reduce moisture buildup.

Never use products made for humans or inappropriate solutions, as these can irritate or damage the ear canal.

Treating Otitis

Only a veterinarian can properly diagnose and treat otitis.

How Treatment Is Managed

Veterinary examination and diagnosis: an otoscope is used to examine the ear canal and eardrum. A sample (cytology) is collected and examined under a microscope to confirm the presence of inflammatory cells, bacteria, yeast, and/or parasites.
Professional cleaning: debris is removed using an appropriate cleanser, and the ears are thoroughly dried.
Targeted medication: ear drops or ointments (antibiotics, antifungals, anti-inflammatories) are prescribed depending on the cause.
Follow-up: a second consultation is often required to ensure complete resolution. Stopping treatment too early may result in relapse.

In more severe or deep infections, oral medications may be prescribed.

Important: do not attempt home self-medication, especially without knowing whether the eardrum is intact. Some products can cause permanent hearing loss.

When to See a Veterinarian

Consult a veterinarian promptly if you notice:

Frequent scratching or head shaking
Redness, pain, unpleasant odor, or abnormal discharge
Decreased hearing or persistent head tilt
Rapid onset of symptoms after swimming or if a foreign object is visible

Even mild signs should be evaluated by a professional, as otitis can progress quickly. Note that with recurrent ear infections, a full evaluation is essential each time, as the underlying cause may differ from one episode to another. Improper treatment can be dangerous or lead to antimicrobial resistance, which is why medications for this condition are not automatically refilled.

Seasons and Risk Factors

Spring and Summer

Increased environmental allergens
Moisture is a major risk factor (swimming, rain, warm and humid weather)

In Summary

Inspect your dog’s ears regularly.
Learn to recognize warning signs: itching, discharge, odor, or pain.
Prevent infections with proper ear care, good hygiene, and thorough drying after water exposure.
Consult a veterinarian at the first signs of a problem.

A consistent ear-cleaning routine and a balanced diet may help reduce the occurrence of otitis. Diet plays a significant role in managing allergic or dermatological ear infections. Ask your veterinarian for advice.