CONDITION
Kennel Cough in Dogs
Kennel cough describes a harsh, distinctive cough that develops when the airways (the windpipe, or trachea, and the larger airways, or bronchi) become inflamed, often after contact with other dogs. The inflammation can be triggered by a range of infectious agents, sometimes several at once, and tends to appear a few days after exposure in places where dogs congregate. The cough itself is typically dry and forceful, sometimes described as honking or as though something is caught in the throat, and it may be the only sign an owner notices. Many dogs remain bright and eating normally throughout, while others develop a softer cough, nasal discharge, or a period of reduced appetite. The intensity and duration can vary considerably depending on which pathogens are involved, the dog's age and vaccination history, and whether complications develop. Puppies, older dogs, and those with existing airway or immune conditions may experience a more pronounced or prolonged course. This page explores what kennel cough looks like in practice, the infectious agents and immune responses that underlie it, how veterinary surgeons distinguish it from other causes of coughing, and the range of approaches used to support dogs through the illness. It also considers when the clinical picture suggests a need for closer monitoring or investigation.
Why this matters now
Kennel cough can affect dogs of any age but is most commonly encountered in settings where dogs congregate in close quarters, such as boarding facilities, dog parks, grooming salons, training classes and shelters. Outbreaks tend to occur in waves. In UK veterinary practice data, consultations for respiratory disease in dogs are lowest in spring and roughly double by autumn.
In most healthy adult dogs, kennel cough follows a self-limiting course over one to three weeks, with the cough gradually diminishing in frequency and intensity. However, some dogs may develop secondary bacterial complications that extend the illness or deepen its effects into the lower airways. Puppies are more prone to severe disease, and in puppies kennel cough can progress to bronchopneumonia, which can be fatal. In weakened or older dogs it can progress to chronic bronchitis. The cough itself may persist for several weeks even after the infectious process has resolved, as the damaged airway epithelium regenerates.
Signals & patterns
Early signals
Harsh, dry cough
A distinctive forceful, dry cough that may sound like honking or goose-like is typically the first sign noticed. The cough may be easily triggered by excitement, pulling on the lead, or gentle pressure on the trachea, and often comes in paroxysms.
Retching or gagging at the end of coughing bouts
Coughing episodes frequently terminate with a retching or gagging motion that may produce small amounts of white foam or mucus. This can sometimes be mistaken for vomiting.
Clear nasal discharge
A mild, clear watery discharge from the nose may develop alongside the cough, reflecting upper airway inflammation and increased mucus production.
Normal energy and appetite initially
In uncomplicated cases, dogs often remain bright, alert, and interested in food and activity despite the persistent cough, which helps distinguish mild kennel cough from more systemic illness.
Later signals
Thick nasal discharge
If secondary bacterial infection develops, the nasal discharge may become thicker, more opaque, and yellow or green in colour, suggesting a deeper or more established infection.
Reduced energy and appetite
Progression beyond simple tracheobronchitis may be accompanied by lethargy and reduced interest in food, suggesting the infection is producing more systemic effects.
Productive or moist cough
A shift from the initial dry, honking cough to a wetter, more productive-sounding cough may indicate that the infection has extended into the lower airways or that significant secretions are accumulating.
Laboured breathing or bluish gums
Laboured breathing, puffing or 'blowing' of the lips, and bluish gums, especially after exercise, are recognised signs of pneumonia. Fever, thick nasal discharge, dullness, loss of appetite and a moist cough together are the published signs that kennel cough has progressed to bronchopneumonia.
Click to read about the biological mechanisms
How this is usually investigated
Kennel cough is often diagnosed based on clinical presentation and history of exposure, though additional diagnostics may be pursued in cases that are severe, atypical, or unresponsive to initial management.
Clinical examination and history
Thoracic radiography
Respiratory pathogen testing
Blood work
Options & trade-offs
Management of kennel cough ranges from supportive care for mild self-limiting cases to more active intervention when complications develop or the patient is at higher risk.
Supportive care and monitoring
For uncomplicated kennel cough in otherwise healthy adult dogs, rest, humidity, avoiding irritants such as smoke and dust, and minimising collar pressure on the trachea may be sufficient while the immune system clears the infection over one to three weeks.
Trade-offs: This approach avoids unnecessary medication but requires owners to monitor for signs of progression. The persistent cough can be distressing to observe, and there is a small risk that uncomplicated cases may develop secondary complications.
Antimicrobial therapy
Antibiotics targeting Bordetella bronchiseptica and other bacterial components may be used when bacterial infection or pneumonia is suspected. International antimicrobial guidelines (ISCAID 2017) advise considering them in the first 10 days only when thick (mucopurulent) nasal discharge comes with fever, lethargy or reduced appetite, because most dogs with thick discharge who stay bright and eating may recover within 10 days without them.
Trade-offs: Antimicrobials may shorten the course of bacterial infection but do not address viral components of the disease complex. Their use in mild, self-limiting cases contributes to antimicrobial resistance concerns, making case selection important.
Cough suppressants
Antitussive medications may be considered to reduce the frequency and severity of coughing episodes, particularly when the cough is interfering with rest, eating, or sleeping.
Trade-offs: Cough suppression can improve comfort but may be counterproductive if there is a productive component to the cough where clearing secretions is beneficial. They are generally avoided if pneumonia is suspected, as coughing helps clear infected material from the lower airways.
Vaccination
In the UK, vaccines against Bordetella bronchiseptica and canine parainfluenza virus are authorised as intranasal drops, as injections, and as an oral Bordetella vaccine. Vaccination may reduce the severity of illness rather than completely preventing infection.
Trade-offs: Vaccination does not protect against all pathogens in the kennel cough complex, and breakthrough infections can occur. However, vaccinated dogs tend to experience milder and shorter courses of illness. The timing of vaccination relative to exposure affects its protective value.
Common misconceptions
"Kennel cough only occurs in kennels"
Despite its name, kennel cough can be acquired wherever dogs come into close contact with each other, including dog parks, grooming salons, veterinary waiting rooms, training classes, and neighbourhood walks. Any environment where respiratory droplets can be shared between dogs presents a potential transmission opportunity.
"Vaccination completely prevents kennel cough"
Available vaccines target specific pathogens within the kennel cough complex, primarily Bordetella bronchiseptica and canine parainfluenza virus. Since multiple different organisms can cause similar clinical signs, vaccinated dogs may still develop respiratory infections from agents not covered by the vaccine. Vaccination tends to reduce the severity and duration of illness rather than providing complete protection.
"A coughing dog always needs antibiotics"
Many cases of kennel cough are caused by viral agents against which antibiotics are ineffective. In uncomplicated cases affecting otherwise healthy adult dogs, the infection is often self-limiting and resolves with supportive care alone. Antimicrobial therapy is most appropriate when there is evidence of bacterial involvement, secondary complications, or the patient is at higher risk.
Related conditions
Chronic Bronchitis in Dogs
Chronic bronchitis in dogs shares the hallmark sign of a persistent cough, though the inflammation in chronic bronchitis tends to affect the deeper airways in the lungs rather than mainly the trachea and large bronchi, and the pattern typically unfolds over months rather than days. Distinguishing between the two can require consideration of the timeline, the dog's history of exposures, and sometimes further investigation of the lower respiratory tract.
Pneumonia
Pneumonia can develop as a complication of kennel cough when infection or inflammation extends from the upper airways into the lungs themselves, particularly in puppies, older dogs, or those with compromised immune or respiratory function. The transition from a dry, upper-airway cough to signs suggesting deeper lung involvement (such as increased breathing effort, a softer or more productive cough, or systemic illness) often prompts veterinary surgeons to consider whether pneumonia has developed.
Tracheal Collapse
Tracheal collapse can produce a cough that owners sometimes describe in similar terms (honking, dry and persistent), and the two conditions may occasionally be considered alongside one another when a dog presents with characteristic upper-airway sounds. The key distinction often lies in the chronicity and triggers: tracheal collapse tends to worsen gradually over time and may be provoked by excitement or pressure on the neck, while kennel cough typically follows recent exposure and resolves within weeks.
Laryngeal Paralysis
Laryngeal paralysis affects the larynx (voice box), which can also become inflamed in kennel cough, but through a different mechanism: loss of normal nerve function rather than infectious inflammation. Both conditions can cause respiratory noise and difficulty, though laryngeal paralysis typically causes noisy, raspy breathing on breathing in (stridor) and a changed bark, with coughing and gagging also possible, and the onset and progression tend to differ markedly from the acute, post-exposure pattern seen in kennel cough.
Canine Parvovirus
Canine parvovirus shares with kennel cough the context of rapid spread in environments where young dogs congregate, and both are important considerations in the differential diagnosis of illness in puppies exposed to other dogs. The clinical picture differs substantially: parvovirus typically causes severe gastrointestinal signs rather than respiratory ones. However, the overlapping epidemiology and vaccination schedules mean the two infections are often discussed together in preventive health planning.
Keeping a coughing dog away from other dogs helps reduce transmission. Most viruses involved are shed for only about a week or so, but Bordetella bronchiseptica can be shed for weeks to months by dogs that appear well, so the infectious period cannot be judged from the cough alone. Using a harness rather than a collar avoids putting pressure on the inflamed trachea that can trigger coughing bouts. Maintaining a calm environment with adequate humidity and minimal exposure to irritants supports recovery. Lethargy, loss of appetite, laboured breathing or a fever (which can only be confirmed with a thermometer) are signs that the infection may have spread to the lungs as pneumonia, rather than signs of uncomplicated kennel cough.
Last reviewed: 9 October 2026 · Dr Alastair Greenway MRCVS