How to recognize hearing loss in dogs, likely causes (congenital, age-related, otitis, ototoxicity), when to act, and how BAER testing fits in.

Quick Assessment

Is this an emergency? No, usually not — except when deafness is sudden, associated with pain, fever (>103°F / 39.4°C), head tilt, or other neurologic signs. Those situations need urgent veterinary attention.

Most common cause: chronic or recurrent ear disease (otitis) and age-related hearing loss (presbycusis).

When to see a vet: sudden loss, signs of ear pain/discharge/head tilt, or if hearing problems affect safety or quality of life.

What this symptom looks like

Owners sometimes aren’t sure whether a dog is truly deaf. Common observations:

• Your dog doesn't respond to common sounds (doorbell, name, clapping) but will still react to visual cues or vibration.
• Sleeping through loud noises that used to wake them.
• Startling when touched unexpectedly but not by sound.
• Not obeying voice commands but responding to hand signals.

Possible causes (ranked by likelihood)

Sources: Merck Veterinary Manual (Ear disease; Evoked potentials) and standard veterinary references.

Decision tree — quick help for common presentations

• If hearing loss is gradual over months in an older dog → likely presbycusis → schedule a non-urgent vet visit for baseline exam and discuss training changes and safety.

• If hearing loss is present from puppyhood (especially in Dalmatians, white-coated pups) → likely congenital deafness → arrange BAER testing (see below) to confirm and plan training/environment.

• If hearing loss is accompanied by ear odor, head shaking, ear scratching, discharge, redness, swelling → likely otitis externa/otitis media → see your vet within 48–72 hours for ear exam, cleaning, and possible culture and treatment.

• If hearing loss is sudden (hours to 48 hours) and there are vestibular signs (head tilt, circling, nystagmus, ataxia) → likely inner ear disease, labyrinthitis, or drug-induced ototoxicity → seek urgent veterinary care.

• If the dog recently received aminoglycoside antibiotics (systemic or topical) or cisplatin → suspect ototoxicity → contact your vet immediately (possible emergency).

• If hearing loss follows head trauma → possible tympanic membrane rupture, skull fracture, or central injury → urgent evaluation and imaging may be needed.

• If there are systemic signs such as fever (>103°F / 39.4°C), lethargy, or profound neurologic deficits → emergency vet now.

Home assessment steps (what to check and what to measure)

BAER testing (Brainstem Auditory Evoked Response)

• What it is: BAER is an objective electrical test that measures the auditory pathway’s response to sound stimuli via electrodes placed on the scalp/skin. It is the gold standard for confirming deafness (especially congenital) because it doesn't rely on behavioral responses.
• How it’s done: The dog is usually mildly sedated or restrained; earphones deliver clicks and waveforms are recorded. The test can detect absent or reduced waves and usually distinguishes normal hearing from severe/profound hearing loss. (Merck Vet Manual: evoked potentials)
• Interpretation: Absent BAER waves indicate severe-to-complete sensorineural hearing loss. A reduced or delayed response can indicate partial loss or conductive attenuation. In some cases, bone-conduction testing is used to differentiate conductive vs sensorineural loss.
• Practical notes: BAER is commonly used to screen puppies (e.g., Dalmatians) and to document unilateral vs bilateral deafness. It does not treat loss — it confirms it and helps with breeding decisions and management.
• Cost and availability: Costs and need for sedation vary by clinic; specialty hospitals or universities provide testing.

When it's an emergency — clear red flags

Seek immediate veterinary care (same day) if any of the following occur:

• Sudden bilateral or unilateral hearing loss over hours to 48 hours, especially with vestibular signs (head tilt, circling, nystagmus, loss of balance).
• Recent administration of known ototoxic drugs (aminoglycosides, high-dose loop diuretics, cisplatin) with new hearing loss.
• Signs of severe ear pain, intense head shaking, severe bleeding from ear or ear canal, or a ruptured eardrum after trauma.
• Fever >103°F (39.4°C), lethargy, anorexia, or other systemic signs.
• Progressive neurologic signs (seizures, collapsing, facial paralysis, inability to stand).

When to schedule a vet visit (non-urgent but necessary)

• Gradual hearing loss over weeks to months.
• Recurrent ear infections (≥3/year) or chronic discharge/odor.
• Suspected congenital deafness (especially in affected breeds) to arrange BAER testing and management.
• Safety concerns (dog unaware of traffic, not responding to owners) or behavior changes tied to hearing loss.

Home care (safe things to do while monitoring)

• Don’t insert cotton swabs or sharp objects into the ear canal.
• Keep ears dry and avoid bathing the head until cleared by your vet.
• If your vet prescribed topical ear medication in the past, do not reuse without instruction — some contain aminoglycosides (neomycin, gentamicin) which can be ototoxic if the eardrum is ruptured.
• Use visual cues and hand signals for training; consider a vibration collar temporarily for recall training (discuss with trainer/vet first).
• Improve safety: leash-walk near roads, use gates/stairs safely, supervise around hazards that rely on hearing (cars, wildlife).
• Record observations: note onset, which sounds the dog still responds to, and any changes in balance or behavior.

What to tell your vet (helpful, time-saving information)

Prepare this information before the appointment:

• Exact onset: when you first noticed the change, and whether it was sudden (hours–days) or gradual (weeks–months).
• Which ear(s) seem affected (left, right, both) and how you tested this at home.
• Any recent medications (prescription, topical ear meds, ear drops, injectable antibiotics), including dose and dates.
• History of ear infections: number of episodes in past year, treatments used, and whether tympanic membranes were examined.
• Recent trauma, exposure to toxins, or known ingestion of anything unusual.
• Breed (especially Dalmatians, Bull Terriers, Australian Cattle Dogs, English Setters) and age of the dog.
• Any vestibular signs (head tilt, circling, stumbling), fever readings, appetite, and energy level.

Testing and likely next steps at the clinic

• Otoscopic ear exam to inspect the ear canal and tympanic membrane.
• Cytology and possible culture of ear discharge if present.
• Neurologic exam to assess central vs peripheral causes.
• BAER testing (for objective hearing assessment) if congenital deafness or unclear behavioral testing.
• Imaging (skull CT or MRI) if middle/inner ear disease, trauma, or neoplasia is suspected.

Sources and further reading

• Merck Veterinary Manual: Ear (otitis externa/media) and Evoked Potentials (BAER). https://www.merckvetmanual.com/
• American Veterinary Medical Association (AVMA): Diagnostic Tests — Evoked Potentials/BAER resources. https://www.avma.org/

Frequently Asked Questions