Kennel Cough in Dogs: Symptoms, Sound, Treatment and How Long It Lasts

What Causes Kennel Cough?

Kennel cough isn't one germ. A dog can be infected with two or more at once:^1,3

• Bacteria: Bordetella bronchiseptica (the best known, which is why the condition is often called "Bordetella"), Mycoplasma species and Streptococcus equi subspecies zooepidemicus
• Viruses: canine parainfluenza, canine adenovirus type 2, canine influenza (H3N2 and H3N8), canine respiratory coronavirus, canine herpesvirus-1 and canine distemper virus

Stress, poor ventilation, and extremes of temperature and humidity make dogs more likely to get sick, and can make the illness worse.³

How Do Dogs Get Kennel Cough?

• Through the air: breathing in droplets from an infected dog's cough or sneeze.^1,2
• Close contact: licking and nuzzling.¹
• Contaminated objects: shared toys, bowls, bedding, and people's hands and clothing. Some of these germs survive in the environment for weeks.^1,2

High-risk places include boarding kennels, daycares, groomers, shelters, pet stores, dog shows, dog parks and veterinary clinics.² Because germs spread on hands, clothing and shared items, a dog can catch kennel cough without obvious contact with a sick dog. Dogs are often contagious before they show any signs.¹

Kennel Cough Symptoms: What Does It Sound Like?

The classic sign is a sudden, frequent, dry "goose honk" cough. Many owners think their dog has something stuck in its throat, because the cough is often followed by gagging or retching, sometimes bringing up white froth.^1,3 Other signs include:^1,2

• Coughing that gets worse with exercise, excitement or pressure on the neck
• Sneezing
• A runny nose and watery eyes
• Mild fever, low energy or a reduced appetite in some dogs

Most dogs with mild kennel cough stay bright and keep eating. Some infected dogs don't cough at all.¹ Signs usually start suddenly, 5 to 10 days after exposure.³ See also our page on other causes of coughing in dogs.

How Long Does Kennel Cough Last, and How Long Is It Contagious?

• Incubation: about 6 days on average after exposure to Bordetella, with a range of 2 to 10 days.²
• How long it lasts: most mild cases clear up within 7 to 10 days.^1,2 The cough usually eases within the first 5 days, but it can linger for 10 to 20 days.³
• How long it's contagious: dogs can spread Bordetella for up to 8 weeks, possibly longer, even after the cough has stopped.² Keep your dog away from other dogs until it has fully recovered, and ask your vet when it's safe to return to daycare or boarding.^1,2

What Can Be Mistaken for Kennel Cough?

Not every honking cough is kennel cough. Coughing can also come from other airway, lung and heart problems, which is why vets often take chest X-rays to rule out other causes, especially if the cough lasts or the dog seems unwell.³ Vets can often trigger the typical kennel cough by gently pressing on the windpipe during an exam.³ Distemper can also cause respiratory signs.¹ Learn more about distemper, dog flu and heart disease in dogs.

Diagnosis

Mild cases are usually diagnosed from the dog's signs and recent exposure to other dogs.^1,3 Testing is recommended during outbreaks or when a dog gets worse despite supportive care. This can include swabs from the nose or throat tested by PCR, blood tests and chest X-rays.^1,3

Kennel Cough Treatment

There's no single drug that cures kennel cough. Most dogs recover with rest and supportive care.^1,2

• Rest: limit exercise and excitement, which trigger coughing.¹
• Avoid neck leashes: pressure on the windpipe easily sets off coughing, so a harness is a sensible alternative to a collar.^1,3
• Antibiotics are often not needed, because many cases are viral. Guidelines suggest watching dogs with mild signs, who are still eating and alert, for up to 10 days. Antibiotics, usually doxycycline for 7 to 10 days, are recommended if a dog has thick nasal discharge along with fever, lethargy or a poor appetite.⁴ Pneumonia needs vet-directed treatment, often guided by testing.^1,3
• Cough suppressants can help a persistent dry cough, but only on your vet's advice. They should not be used if pneumonia is present.^3,2
• Severe cases may need anti-inflammatory medication, IV fluids, nebulization or, rarely, oxygen therapy in hospital.^1,2

See our pages on kennel cough treatment and cough medicine for dogs.

Kennel Cough Home Care

For a dog with a mild case that is eating, drinking and alert:

• Keep your dog quiet and rested, and avoid neck leashes.¹
• Keep it away from other dogs, and don't share bowls, toys or bedding.^1,2
• Clean bowls, toys and surfaces. Household bleach diluted 1 part to 32 parts water is effective against Bordetella.²
• Watch closely for the warning signs above, and call your vet if your dog gets worse or isn't improving.¹

See our full guide to kennel cough treatment at home.

Don't give human cough medicine without your vet's advice. Some cough syrups and over-the-counter medicines contain xylitol, a sweetener that can cause a dangerous drop in a dog's blood sugar.⁵

Kennel Cough Vaccine (Bordetella Shot)

• Who needs it: the Bordetella vaccine is "noncore," meaning it's recommended based on lifestyle. It's advised for dogs at higher risk, such as those that board, go to daycare or groomers, or mix with many other dogs.^6,1
• Types: it's available as an intranasal (nose drop), oral or injectable vaccine, often combined with parainfluenza. Intranasal and oral versions are a single dose; the injectable needs two doses 2 to 4 weeks apart. Boosters are given yearly.^6,2
• Puppies can start as early as 6 to 8 weeks of age.²
• What it does: it doesn't prevent every case, because many different germs cause kennel cough, but vaccinated dogs may have milder signs and shed less bacteria.²
• Other vaccines: the core distemper and adenovirus vaccines help too (many combination shots also include parainfluenza), and a canine influenza vaccine is recommended where dog flu is circulating.^1,6

For details on types, timing before boarding and side effects, see our guide to the Bordetella (kennel cough) vaccine and our puppy and dog vaccination schedule.

Can Humans or Cats Catch Kennel Cough?

People: of the germs that cause kennel cough, only Bordetella bronchiseptica is known to infect people, and spread from dogs to humans is extremely rare. Most cases have been in people with severely weakened immune systems.^1,2 Owners with weakened immunity may want to ask their vet about the injectable vaccine instead of the intranasal or oral versions.²

Cats: Bordetella, Streptococcus equi subspecies zooepidemicus and canine influenza can also infect cats.¹

Frequently Asked Questions

What are the first signs of kennel cough?

A sudden, dry, honking cough, often followed by gagging or retching, is usually the first sign. Some dogs also sneeze or have a runny nose and watery eyes.

What does kennel cough sound like?

It sounds like a "goose honk," a harsh, dry cough that can make it seem as if your dog is trying to clear something from its throat. Coughing fits often end in gagging or bringing up white froth.

Will kennel cough go away on its own?

Mild cases usually clear up within 7 to 10 days with rest. See a vet if your dog is lethargic, stops eating, has a fever or breathing trouble, or isn't improving.

How long is kennel cough contagious?

Dogs can be contagious before they show signs, and can spread Bordetella for up to 8 weeks or longer, even after the cough has stopped. Ask your vet before returning to daycare or boarding.

How did my dog get kennel cough without seeing other dogs?

The germs spread through the air and on shared objects, hands and clothing, and some survive in the environment for weeks. Dogs can pick it up anywhere many dogs pass through, such as vet clinics, groomers and parks.

Is it worth going to the vet for kennel cough?

Yes, if your dog is a puppy, older or has other health problems, or shows any warning signs such as lethargy, poor appetite, fever or labored breathing. A vet can also rule out other causes of coughing.

Can I give my dog human cough medicine?

Not without your vet's advice. Some human cough syrups contain xylitol, which is dangerous to dogs, and cough suppressants shouldn't be used if pneumonia is possible.

Do I need to disinfect my house if my dog has kennel cough?

Clean bowls, toys, bedding and surfaces, especially if you have other dogs. Diluted household bleach (1 part to 32 parts water) is effective against Bordetella.

Can humans get kennel cough from dogs?

It's extremely rare. Only Bordetella bronchiseptica is known to infect people, mostly those with severely weakened immune systems.

Can kennel cough kill a dog?

Most dogs recover fully, but kennel cough can lead to pneumonia, which can be life-threatening in puppies, older dogs and dogs with other health problems.

Does the Bordetella vaccine prevent kennel cough?

It reduces the risk and severity but doesn't prevent every case, because many different viruses and bacteria cause kennel cough.