Noisy Breathing in Dogs: Stertor and Stridor — Symptom Decision Guide

A practical symptom guide to stertor (snoring) and stridor (high-pitched wheeze) in dogs. Helps owners identify likely causes, urgency, and next steps.

Quick Assessment

• Is this an emergency?

• Most common cause (by context):

• When to see a vet right away: new or worsening noisy breathing lasting >24 hours, noisy breathing plus cough, exercise intolerance, gagging/vomiting, fever (>104°F / 40°C), or any of the emergency signs above.

What this symptom looks like

• Stertor: low‑pitched snoring or snuffling made during breathing, usually originating from the nose, nasopharynx or soft palate. Often loudest when the dog is sleeping, resting, or inhaling through the nose.

• Stridor: a high‑pitched, harsh, often musical inspiratory sound produced by turbulent airflow through the larynx or trachea. Typically heard when the dog inhales and commonly more obvious when excited or exercising.

Likely causes (ranked common → rare)

Less common causes include foreign bodies lodged in the nasal cavity or larynx, infectious rhinitis, allergic disease, neoplasia, and systemic conditions that impair breathing.

Decision tree: symptom + other sign → likely cause → action

• If low‑pitched snoring (stertor) + brachycephalic breed + worse with heat/exercise → likely BOAS or elongated soft palate → action: avoid overheating, use harness, record video, schedule vet evaluation within 48 hours for airway assessment (possible surgical correction).

• If high‑pitched inspiratory noise (stridor) + older large breed + progressive exercise intolerance and change in bark/voice → likely laryngeal paralysis → action: seek veterinary appointment within 24–48 hours; if breathing severely noisy at rest or collapsing, go to emergency.

• If honking cough + intermittent stridor + small breed + worse with excitement or collar pressure → likely tracheal collapse → action: stop using neck collars (use harness), reduce excitement, schedule vet within 72 hours; emergency if distress or collapse.

• If stertor + unilateral nasal discharge or sneezing + young dog or recent upper airway procedure → possible nasopharyngeal polyp or mass → action: record video, schedule prompt vet visit for imaging or scope; emergency if severe breathing difficulty.

• If sudden onset noisy breathing after choking episode, trauma or foreign body exposure → possible airway obstruction → action: emergency vet now.

Home assessment steps (what to check & measure)

When It's an Emergency (red flags)

Seek emergency veterinary care immediately if any of these are present:

• Continuous open‑mouth breathing at rest or obvious effort to breathe.
• Blue, purple, very pale gums or tongue (cyanosis) or loss of consciousness.
• Collapse, fainting, or severe weakness.
• Sudden onset noisy breathing immediately after a choking episode or suspected foreign body ingestion.
• Respiratory rate persistently >50 breaths/min at rest, or temperature >104°F (40°C).
• Blood in nasal discharge or severe facial swelling.

When to schedule a vet visit (non‑urgent but needs attention)

Make a non‑emergency appointment within 24–72 hours if:

• Noisy breathing is new but the dog is bright, eating, and not in distress.
• Stertor or stridor is intermittent, worse with exercise, or there is a chronic cough.
• There is progressive exercise intolerance, voice change, or recurrent respiratory infections.
• Small breed with chronic honking cough or any dog with increasing episodes of gagging.

Home care while you monitor (safe, temporary measures)

• Keep your dog calm and minimize excitement — stress worsens airway noises.
• Remove neck collars and use a chest harness for walks (helps if tracheal collapse suspected).
• Avoid exercise in hot, humid weather; keep dog cool and hydrated.
• Use a humidifier or sit in a steamy bathroom with the dog for 10–15 minutes if mucous congestion is suspected — this may temporarily ease stertor from nasal/pharyngeal congestion.
• Record videos of episodes and note timing and triggers.

What to tell your vet (key information to prepare)

• Breed, age, weight, and whether the dog is brachycephalic.
• Exact onset and course: when did it start, has it changed, frequency/duration of episodes.
• When the noise occurs (sleeping, at rest, during exercise, with excitement, after eating/drinking).
• Sound description: low snore, high squeal, honk, cough, whether it’s inspiratory or expiratory.
• Respiratory rate at rest (breaths per minute), temperature reading, gum color, and CRT if measured.
• Any associated signs: cough, gagging, vomiting, nasal discharge, drooling, decreased appetite, lethargy.
• Recent events: heat exposure, trauma, anesthesia, or choking episode, and any current medications.
• Videos of the noisy breathing and any patterns you’ve noticed.

Important thresholds and timeframes to remember

• Respiratory rate at rest >40–50 breaths/min — concerning; >50 is emergency territory.
• Temperature >104°F (40°C) — emergency.
• Mucous membrane color: blue/pale — immediate emergency.
• New or rapidly worsening noisy breathing lasting >24 hours — seek veterinary attention.

Final notes on common specific causes

• BOAS / Elongated soft palate: often improved with weight loss, cooling, activity management, and surgical correction in pending cases. Early assessment is recommended for brachycephalic breeds.
• Laryngeal paralysis: often progressive; surgical options exist and timely referral improves outcomes.
• Tracheal collapse: managed medically (cough suppressants, anti‑inflammatories, weight control) or surgically in severe cases; harnesses help.
• Nasopharyngeal mass/polyp: usually diagnosed with imaging or scope and treated surgically or medically depending on cause.

Sources: Merck Veterinary Manual (respiratory disorders in dogs), veterinary clinical references on BOAS, laryngeal paralysis and tracheal collapse.

Frequently Asked Questions