TL;DR: Sudden hearing loss in dogs is a medium-priority medical concern that requires a veterinary examination within 24–48 hours to identify treatable causes and potentially restore hearing.
What does it mean if my dog suddenly loses their hearing?
Sudden total hearing loss, or acute deafness, occurs when a dog who previously had normal hearing abruptly loses the ability to perceive sound. Unlike age-related hearing loss, which is gradual, sudden deafness is often startling for the dog and may lead to increased anxiety or confusion. Common causes include:
- Severe inflammation or infection of the inner ear
- Deep wax impaction
- Exposure to ototoxic drugs
- Neurological changes
Is sudden hearing loss in dogs considered a medical emergency?
The urgency level for sudden hearing loss is classified as Medium. While your dog is likely not in immediate life-threatening danger, early intervention is critical for the following reasons:
- A veterinary examination is required within 24 to 48 hours to maximize the chance of recovery.
- Prompt treatment of inflammatory or infectious causes may help restore some or all hearing.
- Conditions accompanied by a head tilt, circling, or stumbling should be treated with higher priority as they may indicate vestibular disease.
How can sending a photo help determine why my dog can't hear?
Providing a high-quality photo of your dog’s ear canals can be incredibly helpful for a triage professional. A clear image allows the vet to identify:
- Visible obstructions, such as a foreign object or grass awn
- Heavy discharge or wax buildup
- Significant redness and swelling of the ear flap
- Whether the hearing loss is due to a treatable external blockage or requires advanced diagnostic testing of the inner ear
Clinical Context (Merck Veterinary Manual)
Sudden hearing loss in dogs can be caused by acquired sensorineural deafness resulting from intrauterine infection or toxins, otitis interna or meningitis, mechanical or noise trauma, ototoxicity, anesthesia, or neoplasms. Ototoxic drugs and chemicals, especially aminoglycoside antibiotics, antineoplastic drugs (cisplatin), salicylates, diuretics (ethacrynic acid, furosemide), and antiseptics (chlorhexidine) can cause permanent toxicity, with aminoglycosides being the most common. High frequencies are typically affected first, and the toxicity may appear weeks after treatment. Anesthesia for teeth or ear cleaning can also rarely result in bilateral deafness. Hunting or military dogs exposed to loud noises such as gunfire may experience cumulative hearing loss. Unilaterally deaf animals primarily show an inability to localize sound.
Chapter: Toxicology, Neurology, Anesthesia
Source: The Merck Veterinary Manual, 11th Edition (Page 519)