When a dog pants, they breathe rapidly with their mouth open, often with their tongue hanging out. In many cases, this is completely normal: dogs pant to cool themselves down or after physical activity.

But sometimes, a dog may start panting even when it isn’t particularly warm and they’ve just been resting. Why does this happen, and should you be concerned?

One cause of panting in dogs: stress

When a dog experiences a situation they find stressful, their sympathetic nervous system becomes activated. Their heart rate increases, their breathing speeds up, and their pupils dilate. Their entire body prepares to face danger through a fight-or-flight response.

If your dog is panting for no obvious reason, look for other signs of stress, including:

• Ears pinned back
• Avoiding eye contact
• The whites of the eyes becoming visible
• A tense body posture
• A low or tucked tail

If you notice some of these signs, try to identify what is making your dog uncomfortable and, if possible, remove them from the situation now and in the future. Dogs that are repeatedly exposed to stressful situations may develop chronic stress, which can negatively affect their health.

Another cause of panting in dogs: pain

Pain is a highly individual experience and can be expressed in many different ways. Even if your dog is not whining and continues their normal activities, they may still be experiencing discomfort.

Several subtle signs can indicate that your dog is in pain or not feeling well, and panting is one of them.

Heart and respiratory problems

Certain heart conditions can also cause panting. When the heart is not functioning properly, the body may receive less oxygen. As a result, the dog may breathe more rapidly to compensate.

Panting can also be associated with inflammation or obstruction of the airways. Some brachycephalic breeds—such as bulldogs and pugs—are naturally more prone to breathing difficulties, which can lead to increased panting.

When should you consult a veterinarian?

If your dog regularly pants without it being related to heat or physical activity, it is important to consult your veterinarian. They can determine whether the panting is linked to stress, pain, a heart condition, or a respiratory issue, and recommend appropriate treatment or management options.

When panting becomes an emergency

In some cases, panting may be a sign of a veterinary emergency.

Contact a veterinary clinic immediately if your dog is also showing any of the following signs:

• A bluish tongue
• Difficulty breathing
• Difficulty moving
• Severe weakness
• Unusual behaviour or confusion

If possible, call the clinic before you arrive so the team can prepare to care for your dog as quickly as possible.