Increased panting in an older dog is almost always worth investigating. While all dogs pant to cool down, senior dogs who pant heavily at rest, at night, or without an obvious trigger like heat or exercise often have an underlying medical issue driving it. The causes range from manageable conditions like pain or medication side effects to more serious problems like heart disease or hormonal imbalances.
A healthy dog at rest breathes 15 to 30 times per minute. If your older dog consistently breathes faster than 30 breaths per minute while resting or sleeping, something is off. You can count this yourself: watch your dog’s chest rise and fall for 30 seconds, then double the number.
Heart Disease and Fluid Buildup
Congestive heart failure is one of the most common causes of heavy breathing in older dogs. In left-sided heart failure, the heart’s main pumping chamber struggles to push blood out efficiently, often because a valve has narrowed or started leaking. Blood backs up, pressure builds in the lungs, and fluid seeps into lung tissue. That fluid makes it harder for your dog to get enough oxygen, so they pant to compensate.
Right-sided heart failure looks a bit different. Blood pools in the abdomen instead of the lungs, and you may notice a swollen belly (from fluid accumulation) or swelling in the legs. Both types can cause persistent coughing, especially when your dog is resting or sleeping, along with loss of appetite, reduced energy, and pale or bluish gums. If you notice your dog coughing at rest combined with heavy panting, heart disease is high on the list of possibilities.
Heartworm disease can also lead to heart failure by blocking blood vessels between the heart and lungs, causing scarring and increased pressure in the pulmonary arteries. Dogs on consistent heartworm prevention are protected, but dogs with gaps in coverage may be at risk.
Cushing’s Disease
Cushing’s disease causes the adrenal glands to pump out too much cortisol, the body’s main stress hormone. Excessive panting is one of the hallmark signs in dogs, and it’s specific to dogs (cats with Cushing’s don’t typically pant this way). The excess cortisol keeps the body in a state of low-grade stress, which drives the panting even when your dog is otherwise calm and cool.
Other signs to watch for include increased thirst and urination, a pot-bellied appearance, thinning skin, hair loss, and increased appetite. Cushing’s tends to develop gradually, so many owners chalk up early symptoms to “just getting old.” If your dog is panting more and also drinking noticeably more water than usual, mention both to your vet.
Pain
Dogs are notoriously good at hiding pain, and panting is one of the subtle ways it leaks through. Arthritis, pancreatitis, back problems, dental disease, and internal discomfort can all trigger heavy breathing. A dog with significant abdominal pain from pancreatitis, for instance, may pant heavily even while lying still.
Pain-related panting often looks restless. Your dog may shift positions frequently, have trouble settling, or pant more at certain times (like after getting up from a nap, when stiff joints are at their worst). If the panting comes and goes depending on activity or position, pain is a likely contributor.
Laryngeal Paralysis
This condition affects the muscles that open the airway at the back of the throat. When those muscles stop working properly, the airway doesn’t open fully, and your dog has to work harder to breathe. The signature clue is a raspy, noisy quality to the breathing, almost like a honking or stridor sound that’s louder than normal panting.
Laryngeal paralysis is especially common in large-breed older dogs like Labrador retrievers. It tends to worsen with excitement, exercise, stress, or hot and humid weather. In severe cases, a dog can go from heavy panting to a breathing crisis quickly, making this one to catch early.
Cognitive Dysfunction (Dog Dementia)
Just as some elderly people develop dementia, older dogs can develop cognitive dysfunction syndrome. One of the first signs many owners notice is disrupted sleep. Your dog wakes in the middle of the night, paces, pants, whines, or seems disoriented. This nighttime restlessness is sometimes called “sundowning” because symptoms tend to worsen in the evening and overnight.
During the day, these dogs may seem more anxious, get stuck in corners, stare at walls, or lose interest in walks. The anxiety component is what drives the panting. If your dog’s heavy breathing is concentrated at night and paired with aimless wandering or confusion, cognitive decline is worth discussing with your vet.
Other Medical Causes
Several additional conditions can cause panting in senior dogs:
- Lung or airway cancers. Tumors affecting the throat, windpipe, or lungs become more common with age and can physically obstruct airflow or reduce the lungs’ capacity to exchange oxygen.
- Chronic bronchitis. Long-term inflammation reduces the flexibility of the airways and lungs, leading to heavy breathing and a persistent cough.
- Pneumonia. Bacterial, viral, or fungal infections inflame the lungs. You’ll typically also see coughing, nasal discharge, fever, lethargy, and reduced appetite.
- Pulmonary hypertension. High blood pressure in the lung arteries forces the heart to work harder. It can cause coughing, fainting, and in serious cases, collapse.
Medications That Cause Panting
If your older dog takes prednisone or prednisolone (common steroids prescribed for allergies, joint inflammation, or immune conditions), panting is a well-known side effect, especially at higher doses or with long-term use. Other side effects at these doses include increased thirst, behavioral changes, vomiting, and diarrhea. If the panting started or worsened after beginning a new medication, that connection is worth flagging for your vet. Don’t stop the medication on your own, since abruptly stopping steroids can cause serious problems.
How to Tell Normal Panting From a Problem
Normal panting happens after exercise, during warm weather, or when your dog is excited. It stops once they cool down or calm down. Problem panting looks different: it happens at rest, at night, in a cool room, or without any obvious trigger. It may be louder, harsher, or more labored than your dog’s usual panting. Sometimes you’ll notice your dog’s belly pushing in and out with effort, which signals they’re working harder than normal to breathe.
Start by counting your dog’s resting respiratory rate a few times over several days. If it’s consistently above 30 breaths per minute while sleeping or fully relaxed, bring that number to your vet. It gives them a concrete data point and helps them decide which direction to investigate first.
Signs That Need Urgent Attention
Some panting patterns signal a genuine emergency. Check your dog’s gum color by gently lifting their lip. Healthy gums are a bubble-gum pink. Gray, blue, or purple gums mean your dog isn’t getting enough oxygen, and this requires immediate veterinary care. Pale or white gums can indicate shock, anemia, or poor circulation. Cherry red gums may point to heatstroke or toxin exposure. Yellow gums suggest liver disease.
Other red flags alongside heavy panting include collapse or fainting, a visibly swollen abdomen, extreme lethargy or weakness, and breathing that involves open-mouth gasping with the neck extended. Any of these combined with panting warrants an emergency vet visit rather than waiting for a regular appointment.
What Your Vet Will Look For
Expect a thorough physical exam as the starting point. Your vet will listen to the heart and lungs, feel the abdomen, check gum color, and assess your dog’s overall body condition. From there, blood work and chest X-rays are the most common next steps. Blood work can reveal hormonal imbalances like Cushing’s disease, signs of infection, or organ dysfunction. Chest X-rays show fluid in the lungs, an enlarged heart, masses, or signs of pneumonia.
Depending on what they find, your vet may recommend additional testing. The specifics will depend on which condition they suspect, but the combination of your observations at home (when the panting happens, what else has changed, how long it’s been going on) and those initial diagnostics usually narrows things down efficiently. Keeping a brief log of when your dog pants, how long it lasts, and what else you notice can be genuinely helpful.