Pneumonia in dogs is an inflammation of the lungs and airways that causes breathing difficulties and reduces oxygen levels in the blood. It can range from mild to life-threatening, and it has several distinct forms depending on what triggers it. Understanding the type of pneumonia your dog has is key to getting the right treatment and knowing what to expect.
Types and Causes of Canine Pneumonia
The most common cause of pneumonia in dogs is a viral infection of the lower respiratory tract. Viruses like canine distemper, canine influenza, adenovirus, and parainfluenza damage the airways, which then leaves the lungs vulnerable to secondary bacterial infection. So while a virus often starts the process, bacteria frequently make it worse.
Bacterial pneumonia can also develop on its own. Bordetella bronchiseptica, one of the bacteria behind kennel cough, is among the most common culprits and spreads easily between dogs, particularly those that are very young, elderly, or have weakened immune systems.
Aspiration pneumonia is a distinct and common form caused by inhaling foreign material into the lungs. This can happen when a dog vomits and breathes in stomach contents, chokes while eating or drinking, or receives liquid medication improperly. Dogs with swallowing disorders are at heightened risk. Megaesophagus, a condition where the esophagus loses its ability to move food into the stomach normally, is one of the most significant risk factors. Dogs with laryngeal paralysis or cleft palate, and those recovering from anesthesia, are also more prone to aspirating material into their lungs.
Fungal pneumonia is less common but tends to be more difficult to treat. Several types of fungi can infect the lungs, and these infections are often tied to geographic regions. Dogs in certain parts of the United States may be exposed to fungal organisms in soil or decaying plant matter that can establish infections deep in the lung tissue.
Symptoms to Watch For
The hallmark signs of pneumonia in dogs are a productive (wet-sounding) cough, labored or rapid breathing, and decreased energy. Many dogs stop eating or eat significantly less than usual. Fever is common, though not always obvious to owners without a thermometer. A healthy dog at rest breathes roughly 15 to 30 times per minute. If your dog’s breathing rate is consistently elevated beyond that, or if you notice their sides heaving or their nostrils flaring with each breath, those are signs of respiratory distress.
Nasal discharge, particularly if it’s thick or colored, can accompany pneumonia. Some dogs adopt unusual postures, like extending their neck forward or refusing to lie down, because certain positions make breathing harder. In severe cases, the gums or tongue may appear bluish, which signals dangerously low oxygen levels and requires immediate veterinary attention.
How Veterinarians Diagnose Pneumonia
Chest X-rays are the primary tool for confirming pneumonia. Veterinarians typically take three different views to visualize all parts of the lung field. The most common finding is a cloudy or dense pattern affecting one or more lung lobes, most often in the lower front portions of the chest. In aspiration pneumonia specifically, the lower front regions are almost always the areas affected, since gravity pulls inhaled material there.
Beyond imaging, your vet will listen to your dog’s lungs with a stethoscope, checking for crackles or areas where normal breathing sounds are muffled. Blood work helps assess the overall infection response and oxygen levels. In some cases, a sample of fluid from the airways may be collected to identify the specific bacteria or organism involved, which helps guide treatment choices.
Treatment and Recovery
Bacterial pneumonia is treated with antibiotics. Historically, veterinarians prescribed several weeks of antibiotics, but recent evidence supports shorter courses of 7 to 10 days for uncomplicated cases, particularly aspiration pneumonia. More severe infections, or those involving resistant bacteria, still require longer treatment.
Dogs with moderate to severe pneumonia often need supplemental oxygen, delivered through nasal tubes or an oxygen enclosure at the veterinary hospital. Some critically ill dogs require mechanical ventilation. Nebulization with saline can help hydrate and loosen mucus in the airways, making it easier for your dog to cough up secretions.
A technique called coupage is one of the most useful things owners can do at home during recovery. You cup your hand and gently, rapidly tap different areas of your dog’s chest wall. This vibration helps loosen mucus trapped deep in the lungs so your dog can cough it up. Your vet can demonstrate the proper pressure and technique. For small dogs, use one hand and be especially gentle. Aim for at least four sessions per day, and allow light exercise afterward to encourage productive coughing.
Keeping your dog well-hydrated is also important, since adequate fluid intake helps thin respiratory secretions. Your vet may recommend using a humidifier or bringing your dog into a steamy bathroom for short periods.
Survival Rates and What Affects Them
Most dogs with straightforward bacterial pneumonia recover well with appropriate treatment. Aspiration pneumonia carries more variable outcomes. Survival rates in published studies range from 30% to 80%, and mortality can approach 25% even with treatment. The wide range reflects how much the severity varies: a dog that aspirates a small amount of food may recover quickly, while a dog with megaesophagus who aspirates large volumes of stomach acid faces a much more serious situation.
Dogs with megaesophagus have roughly 2.5 times the risk of developing aspiration pneumonia compared to dogs without the condition, and they’re prone to repeated episodes. Fungal pneumonia tends to require prolonged treatment, sometimes lasting months, and the prognosis depends heavily on the specific organism and how early the infection is caught.
Is Dog Pneumonia Contagious?
Bacterial and viral pneumonia can spread between dogs, especially in environments where dogs are in close contact, like boarding facilities, shelters, or dog parks. Dogs that are very young, elderly, or immunocompromised are most vulnerable to picking up these infections. Aspiration and fungal pneumonia, by contrast, are not contagious since they arise from individual risk factors rather than transmissible organisms.
Your dog is unlikely to pass pneumonia to you. While a few of the bacteria involved can theoretically affect humans with severely weakened immune systems, dog-to-human transmission is rare.
Prevention
Keeping your dog’s vaccines current is the most effective way to prevent the viral infections that often lead to pneumonia. Core vaccines protect against distemper and adenovirus, two of the major respiratory viruses. For dogs that regularly visit boarding facilities, groomers, dog parks, or training classes, an annual intranasal vaccine against Bordetella and parainfluenza provides additional protection. These vaccines don’t guarantee your dog won’t get sick, but they significantly reduce the chance of severe disease.
For dogs at risk of aspiration pneumonia, prevention focuses on managing the underlying condition. Dogs with megaesophagus often need to eat in an upright position and remain upright for 10 to 15 minutes after meals. Liquid medications should be given slowly and carefully, never squirted forcefully into the back of the throat. If your dog is recovering from anesthesia, monitor them closely during the groggy period when their swallowing reflexes may not function normally.