SYMPTOM
Rapid breathing
Rapid breathing is a breathing rate that is faster than usual for the dog while it is resting or asleep. It is different from open-mouthed panting after exercise or in warm weather. Owners often see the chest or flanks moving quickly, or notice panting that carries on in a dog that is cool and settled. A healthy adult dog that is asleep generally takes fewer than 30 breaths a minute, with each rise and fall of the chest counted as one breath. Signs that a dog is working to breathe include laboured breathing, blowing of the lips, noise with each breath, and gums that look pale or bluish. A fast rate with none of these can still reflect disease.
Heat, Exercise and Normal Panting
Dogs increase their respiratory rate to dissipate heat through panting, particularly after exercise, in warm weather, or in overweight or thick-coated breeds. This form of rapid breathing settles once the dog cools down and rests, and the pattern is typically shallow and open-mouthed rather than laboured. Panting that does not settle once the dog has cooled and rested is a different picture. Heatstroke brings rapid panting with drooling, vomiting, distress, uncoordinated movement and collapse. In a UK VetCompass study of 856 heat-related illness events in dogs, breathing changes were the most commonly recorded sign (68.73%), and the fatality rate rose from 2.21% of mild events to 56.76% of severe events.
Pain and Anxiety
Discomfort from injury, orthopaedic conditions or abdominal pain commonly raises breathing rate as part of a generalised stress response, as does fear or anxiety in unfamiliar situations such as travel. This tachypnoea tends to fluctuate with the dog's emotional state and is often accompanied by pacing or a tense body posture rather than by visible effort on each breath.
Cardiac Disease
Dilated cardiomyopathy reduces the heart's pumping efficiency and can lead to fluid accumulating in or around the lungs, driving a persistently faster resting or sleeping breathing rate. Large and giant breeds, including Dobermanns, Great Danes and Irish Wolfhounds, carry a recognised predisposition. The disease has a long silent phase, and once signs appear they develop over a relatively short time. In heart failure a faster breathing rate comes first and laboured breathing follows, so a sleeping rate above 30 breaths a minute is treated as abnormal.
Blood Loss and Anaemia
Internal bleeding, such as from a ruptured splenic mass associated with haemangiosarcoma, lowers the blood's oxygen-carrying capacity and prompts a faster breathing rate as compensation. Older, larger-breed dogs such as German Shepherds, Golden Retrievers and Labradors are more commonly affected, usually at 8 to 10 years of age. Signs can be subtle, such as weakness. A mass that ruptures can cause sudden collapse with pale gums, a fast heart rate and fast breathing, and sudden death is recorded.
Pulmonary and Airway Disease
Infections such as pneumonia, along with fluid or inflammation within the lung tissue, reduce effective gas exchange and lead to a sustained increase in breathing rate. Younger dogs and those with recent kennel or group exposure are more prone to infectious causes, while chronic bronchial disease is more typical of older, smaller-breed dogs.
Why timing matters
Early observation
A rise in the sleeping breathing rate is often the first outward sign of fluid building up in the lungs, and it appears before laboured breathing does. Most owners do not notice the faster rate, so many dogs with heart failure are first examined only once breathing has become laboured.
Later presentation
Fast breathing with visible effort, pale or bluish gums, weakness or collapse reflects a dog that is short of oxygen or losing blood. Heatstroke, bleeding from a ruptured splenic mass and heart failure can all present this way. A ruptured splenic mass can cause collapse and sudden death, and the published fatality rate for severe heat-related illness in dogs is 56.76%.
Context separates the causes. Panting that follows heat or exercise and settles with rest and cooling is normal. A fast rate in a dog that is cool, rested or asleep is not explained by heat, and the cause cannot be identified from the breathing pattern alone. Listening to the chest, imaging and blood tests are needed to tell heart, lung and blood-loss causes apart.
Conditions commonly associated
Haemangiosarcoma
Shock from blood loss or pericardial effusion causes increased respiratory rate and effort.
Dilated Cardiomyopathy in Dogs
Dilated cardiomyopathy in dogs may lead to rapid breathing when the weakened heart cannot pump effectively, causing fluid to back up into the lungs and prompting compensatory increases in respiratory rate.
Pneumonia
Pneumonia involves infection and inflammation of the lung tissue itself, which impairs oxygen exchange and often triggers rapid, laboured breathing as the animal attempts to compensate for reduced respiratory efficiency.
Congestive Heart Failure in Dogs
In congestive heart failure, fluid builds up in or around the lungs. A faster breathing rate at rest or during sleep is the first change, and laboured breathing follows.
Gastric Dilatation-Volvulus (GDV) in Dogs
Panting, weakness and collapse develop as gastric dilatation-volvulus worsens, after earlier signs of unproductive retching, drooling and a distending abdomen.
When to explore further
When the sleeping or resting rate stays above 30 breaths a minute, or keeps rising across repeated counts
When fast breathing comes with laboured breathing, noise with each breath, pale or bluish gums, weakness, collapse or a swelling abdomen
When panting carries on in a dog that is cool, rested and calm, or the dog tires on exercise it used to manage
When the fast breathing cannot be tied to heat, exercise or excitement, since the heart, lungs and blood cannot be assessed at home
The sleeping breathing rate can be counted while the dog is sound asleep in a cool room, with each rise and fall of the chest counted as one breath over a full minute. The counts can then be compared with the figure of 30 breaths a minute. A record of the counts, the time of day, the temperature and any recent exercise, with a note of gum colour and any cough, gives a vet measured information rather than an impression.
Last reviewed: 9 October 2026 · Dr Alastair Greenway MRCVS