Dog Ear Infection: Symptoms, Causes, and When It Needs a Vet

Dog ear infections are among the most common conditions veterinarians treat — and among the most frequently undertreated at home. If your dog is scratching at their ears, shaking their head, or you've noticed a funky smell coming from their ears, an ear infection is the likely culprit. Understanding why they happen and how to manage them can prevent a manageable problem from becoming a chronic one.

Types of Dog Ear Infections

Otitis Externa

The most common type — infection of the outer ear canal (the visible part of the ear). This is what most people mean when they say "ear infection."

Otitis Media and Interna

Infection of the middle or inner ear. These are more serious, can involve the eardrum, and may cause balance problems, head tilting, and in severe cases, facial nerve paralysis. These always require veterinary care.

Common Causes

Yeast (Malassezia)

Yeast overgrowth is the most common type of ear infection in dogs. The ear canal is warm and dark — perfect yeast territory. Signs include a distinctive musty or "corn chip" odor, dark brown discharge, and intense itching. Yeast infections often develop secondary to allergies or moisture.

Bacteria

Bacterial infections often cause more severe inflammation, pain, and discharge that may be yellow, green, or dark and pus-like. They frequently develop alongside yeast infections.

Ear Mites

Tiny parasites that cause intense itching and a dry, dark (coffee ground-like) discharge. More common in puppies and cats, but dogs can get them too, especially in multi-pet households.

Allergies

The most important underlying cause to address. Dogs with environmental or food allergies often have chronically inflamed ear canals that create the perfect environment for recurrent yeast and bacterial infections. If your dog gets ear infections repeatedly, allergies are almost certainly involved.

Anatomy

Dogs with floppy ears (Cocker Spaniels, Basset Hounds, Labrador Retrievers) are predisposed because the ear flap traps moisture and reduces airflow. Dogs with narrow or hairy ear canals (Poodles, Shih Tzus) face similar challenges.

Moisture

Dogs who swim frequently or are bathed often without thorough ear drying are at higher risk.

Symptoms of Dog Ear Infection

• Head shaking or tilting
• Scratching at the ear(s) — sometimes intensely enough to cause scratches or wounds
• Rubbing the ear on furniture or the floor
• Odor from the ear — musty, yeasty, or foul
• Visible discharge — brown, yellow, or dark
• Redness or swelling of the ear canal or flap
• Sensitivity or pain when the ear is touched
• In severe or middle/inner ear cases: head tilt, loss of balance, circling, vomiting

When to Worry

See a vet if:

• Symptoms persist for more than 24–48 hours
• There is significant discharge, odor, or visible inflammation
• Your dog won't let you touch the ear at all (sign of significant pain)
• Your dog is showing balance problems, head tilt, or seems disoriented
• This is a recurring problem (3rd or more ear infection this year)
• You see a wound or hematoma (blood-filled swelling) on the ear flap from scratching (AAHA Canine Life Stage Guidelines, 2019).

Do not use over-the-counter ear drops, cotton swabs inside the canal, or home remedies like vinegar or alcohol without veterinary guidance. These can worsen the condition or damage an already-compromised ear.

What to Do at Home

Gentle ear inspection: Use a flashlight to look into the outer ear. Note the color, amount, and smell of any discharge.

Ear cleaning (if recommended by your vet): Use only veterinary-approved ear cleaners. Squirt a small amount into the canal, massage the base of the ear gently, then allow your dog to shake. Wipe the outer canal with a cotton ball — never insert a swab into the canal.

Keep ears dry: After swimming or bathing, dry the ears thoroughly with a clean towel. Some vets recommend a small amount of veterinary ear drying solution after water exposure.

Address the root cause: Recurring ear infections need an underlying cause investigation — usually allergies. Ask your vet about allergy testing if your dog has more than 2–3 infections per year.

Still Not Sure if Your Dog Needs a Vet?

When you're not sure if this is wait-and-see or call-tonight, Voyage AI Vet triages in under 2 minutes. Describe what you're seeing in chat, share photos of what you're seeing — your dog's posture, any visible signs, and the affected area, or hop on a live video call if you want a second pair of eyes. Every answer comes with citations to the actual veterinary literature it's pulling from — so you see exactly where the guidance comes from, not just a chatbot's word.

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