SYMPTOM
Change in bark
Owners may observe change in bark in their pet.
Various conditions
This symptom can occur in multiple conditions and warrants further assessment.
Laryngeal Paralysis
Age-related degeneration of the nerves and muscles that open the vocal folds, often part of a wider condition known as geriatric onset laryngeal paralysis and polyneuropathy (GOLPP), prevents the larynx from moving normally during breathing and barking. It is most recognised in older large-breed dogs, particularly Labrador Retrievers and other retriever types, and the bark typically becomes deeper, hoarser, or reduced in volume.
Laryngitis and Vocal Overuse
Excessive or prolonged barking, inhalation of smoke or dust, or a mild viral or bacterial infection can inflame the vocal folds temporarily. The resulting hoarseness usually resolves within days to a couple of weeks once the irritation settles, without leaving any lasting change to the bark.
Laryngeal or Tracheal Mass
Growths involving the larynx, or lymphoma affecting nearby lymph nodes, can physically distort the vocal folds or narrow the airway. Unlike transient laryngitis, the change in bark tends to be gradual and progressive rather than settling with rest.
Hypothyroidism
Reduced thyroid hormone output is sometimes found alongside a deeper or raspier bark, but the link to laryngeal muscle weakness is inconsistent and not fully proven, and correcting the hormone level does not reliably improve the voice change. It is most often diagnosed in middle-aged, medium to large breed dogs, usually alongside other signs such as weight gain, lethargy, and a dull coat, and a dog with a persistent voice change should still be assessed for laryngeal paralysis in its own right.
Why timing matters
Early observation
Early recognition allows prompt assessment and intervention if needed.
Later presentation
Persistent or worsening signs may indicate progression requiring attention.
The significance of this symptom depends on its context, duration, and associated findings.
Conditions commonly associated
Laryngeal Paralysis
Laryngeal paralysis affects the voice box, often causing a hoarse, weak, or altered bark.
Laryngeal Paralysis in Dogs
Laryngeal paralysis causes the cartilages of the larynx to fail to open fully during breathing, which often alters the voice and can produce a hoarse, raspy, or quieter bark. The change in bark may be one of the earlier signs noticed, alongside increased respiratory noise during exercise or excitement.
Hypothyroidism in Dogs
Hypothyroidism can affect the tissues of the larynx, sometimes leading to thickening or swelling that alters vocal quality. Owners may notice a deeper, hoarser, or weaker bark, though this is typically accompanied by other metabolic signs such as weight gain or coat changes.
Pneumonia
Pneumonia involves inflammation and infection of the lung tissue, which can cause coughing, respiratory effort, and general illness that may suppress vocalisation or alter the quality of the bark. The change in bark tends to reflect both discomfort and the systemic nature of the condition.
Lymphoma in Dogs
Lymphoma can involve lymphoid tissue in the throat or chest, which may compress or infiltrate structures involved in vocalisation, leading to a change in bark. This is more common when the disease affects the mediastinal (chest) lymph nodes or laryngeal area.
When to explore further
When the symptom is persistent or worsening
When other signs are present alongside
When daily activities or quality of life are affected
When there is uncertainty about the cause
Noting when this symptom occurs, any triggers, and how it changes over time can provide useful information for veterinary discussions.
Last reviewed: 24 April 2026 · Dr Alastair Greenway MRCVS