Dog Breathing Loud with Mouth Closed: Causes and Veterinary Advice

TL;DR: Loud nasal breathing in dogs, known as stertor, is often caused by nasal congestion or anatomical issues and is generally not an emergency unless the dog shows signs of respiratory distress like pale gums.

What causes loud nasal breathing in my dog and what does it mean?

When a dog breathes loudly with their mouth closed, the sound usually originates from the upper respiratory tract. This is often classified as stertor—a low-pitched, snore-like sound caused by fluid or tissue vibrating in the nasal passages or throat. It can be caused by anything from simple congestion and allergies to anatomical obstructions like a long soft palate, nasal polyps, or foreign bodies lodged in the nasal passage.

How do I know if my dog's loud nasal breathing is a medical emergency?

• Schedule a Veterinary Appointment: This is appropriate if your dog is alert, eating, and has healthy pink gums, as the issue is likely sub-acute.
• Seek Emergency Care: Go to an ER immediately if the loud breathing is accompanied by flared nostrils, an extended neck, or gums that appear pale or blue.

Why should I record a video of my dog's breathing for the veterinarian?

• Overcomes Masking: Dogs often mask their symptoms or breathe differently when they are excited or stressed at the clinic; a video captures their authentic behavior.
• Identifies Specific Issues: A recording allows the vet to differentiate between simple nasal congestion and more serious laryngeal issues by hearing the specific sound and seeing the physical effort.
• Improves Triage: Providing a video helps the veterinary team assess the severity of the situation before the physical exam even begins.