EAR DISCHARGE IN DOGS/CATS
WHAT THIS SYMPTOM USUALLY MEANS
Ear discharge—brown, black, yellow, green, or waxy—signals infection, mites, inflammation, or a foreign object. The color and smell help differentiate causes. Black coffee-ground discharge often means ear mites. Yellow-green discharge often means bacterial infection. Brown, thick buildup often suggests yeast.
Ear discharge should always be evaluated.
MOST COMMON CAUSES
MILD OR SELF-LIMITING CAUSES (COMMON)
• Wax buildup
• Early yeast imbalance
• Moisture after swimming
• Mild allergies
MEDICAL CAUSES THAT NEED DIAGNOSIS (MODERATE CONCERN)
• Yeast infection
• Bacterial otitis
• Mites (especially young cats)
• Thickened ear canals from chronic inflammation
• Foreign body (grass awn, foxtail)
• Food/environment allergies
• Early ruptured eardrum
EMERGENCY CAUSES (HIGH CONCERN)
• Severe pus-like discharge
• Blood in the ear
• Sudden discharge with pain and head tilt
• Neurologic signs (ataxia, circling)
• Deep middle ear infection
• Foxtail lodged deep in canal
RED FLAGS: WHEN THIS IS AN EMERGENCY
• Ear discharge + head tilt
• Ear discharge + vomiting or balance problems
• Dark red/bloody discharge
• Thick pus with severe odor
• Sudden onset after hiking (possible foxtail)
If you’re unsure, treat it as urgent.
AT-HOME CARE YOU CAN START NOW
• Wipe outer ear only—never insert objects into the canal.
• Prevent scratching or shaking with a cone.
• Keep ear dry.
• Do NOT use peroxide, vinegar, or leftover drops.
These steps do not replace a veterinary exam if symptoms continue or worsen.
WHAT A VETERINARIAN WILL CHECK
• Otoscope exam
• Cytology to determine yeast vs bacteria
• Mite evaluation (especially in cats)
• Ear flush under sedation if needed
• Antibiotic/antifungal drops tailored to cytology
• Pain and anti-inflammatory medications
• Imaging for suspected middle ear disease
MOST LIKELY DIAGNOSES (BASED ON 40 YEARS OF CASES)
• Yeast otitis
• Bacterial otitis
• Mites
• Mixed infection
• Allergic otitis
• Chronic canal disease
• Middle ear infection
BREEDS OR AGES AT HIGHER RISK
• Spaniels — chronic otitis externa
• Bulldogs & Labs — allergies
• Cats — mites
• Dogs with floppy ears — moisture retention
• Senior pets — endocrine issues
WHEN YOU SHOULD SCHEDULE A VETERINARY VISIT
- Today: bloody or pus-like discharge
- 48 hours: persistent discharge
- 1 week: mild wax or mild yeast smell
- Monitor: transient wax buildup
EXPECTED RECOVERY TIME
• Mild yeast infection: 1–2 weeks
• Bacterial infection: 2–4 weeks
• Mites: resolves within days of treatment
• Middle ear infection: weeks to months
HOW THIS SYMPTOM RELATES TO LONGEVITY
Chronic ear disease is painful, inflammatory, and associated with systemic allergy burden. Reducing lifetime inflammation supports long-term health and comfort.
WHEN TO CONSIDER A LONGEVITY CONSULT
Recommended for pets with repeated infections, chronic allergies, or endocrine disease affecting skin and ears.
FOR CANCER-RELATED CONCERNS
Ear canal tumors can produce abnormal discharge. If one-sided or persistent despite treatment, visit Pet Cancer Navigator.
FAQ
Is black ear discharge always mites?
Often in cats—rarely in adult dogs.
Can I clean the ear canal at home?
Only the outer flap unless directed by your veterinarian.
Does swimming cause ear discharge?
Moisture significantly increases yeast risk.