Why Do Dogs Cough?
In all species, coughing is a reflex activity, the purpose of which is to clear irritant or foreign materials or infectious agents from the respiratory tract. Receptors present in the walls of the airways detect the presence of such material, and initiate forceful, reflex contractions of the diaphragm and abdominal muscles while increasing outflow pressure through the larynx, resulting in the forced expulsion of mucus and debris from the lungs and airways.
Coughing is a normal protective bodily function, but when it is persistent or severe, or is accompanied by signs of systemic illness such as fever, inappetence, or loss of exercise tolerance, it may be an indicator of a serious problem.
What Are the Causes of Coughing In Dogs?
The causes of a persistent cough can most simply be divided into two types: primary respiratory and cardiac (heart-related) coughs. In some scenarios the two types may coexist, which can obviously make them more difficult to manage.
Infectious Respiratory Disease in Dogs
The most common type of respiratory seen in veterinary clinics is infectious tracheobronchitis, commonly known as 'kennel cough'. Affected dogs have a persistent or paroxysmal loud, harsh cough, which may or may not be followed by the production of frothy mucus. Owners often mistakenly think that the poor dog has something stuck in his/her throat, or that the dog is choking. In fact, the harsh nature of the cough is due to inflammation of the walls of the trachea and bronchial tree, usually without any significant impairment to breathing. Kennel cough in dogs does not usually cause any generalized signs of illness except in very young, very old, or otherwise debilitated animals.
There are several infectious organisms associated with infectious tracheobronchitis, with one called Bordetella bronchiseptica responsible for the majority of cases. Vaccines are available against this disease, and you should certainly consider including this in your dog's vaccination regime if he/she is regularly in contact with other dogs, regardless whether he is kenneled or not.
Your veterinarian may elect to use a course of antibiotics depending on the severity your dog's cough, and cough suppressants such as codeine are sometimes also used, as the cough can be so severe as to prevent your pet (and yourself!) from sleeping, however a cough suppressant should never be used without your vet's advice, as they can sometimes exacerbate the underlying infection by preventing clearance of bacteria from the airway. Encouraging your dog to inhale steam vapor by bringing him to the bathroom and running the shower, or giving a spoon of honey are two natural and safe remedies you can attempt at home.
Infection of the lower airways (bronchitis) or substance of the lungs (pneumonia) tends to produce more severe signs of illness, and most dogs will be depressed due to septicemia or fever. Coughing in these cases is usually softer than that heard with kennel cough, and you may notice a foul smell from your dog's breath. Bacterial and fungal infections are commonly associated with infections at these lower levels of the respiratory tree, and they will generally require more aggressive treatment by your veterinarian.
Parasites such as Oslerus osleri, lungworm, and heartworm can cause coughing through different mechanisms. Parasitic infestation is worth bearing in mind as a possible cause if your dog has not recently received a deworming dose.
Non-Infectious Respiratory Problems
As we all know, dust, smoke and other irritants can cause coughing. Again, this is a normal phenomenon, but chronic exposure can cause secondary changes in your dog's airways, leading to excessive mucus production, thickening of airway walls, loss of normal elasticity, and hypersensitivity. Allergic pneumonitis is a condition which can cause severe respiratory compromise in dogs, and needs to be managed by allergen identification and removal if possible, as well as with prednisolone (a steroid) or other medications to suppress the immune response.
Chronic bronchitis is a common condition of older dogs (most commonly small breeds such as Terriers), which causes a productive cough with wheezing. It is seen much more often in homes in which the pet is exposed to cigarette smoke. Again, treatment usually requires the use of steroid medication, and bronchodilators can also be useful in some cases.
Tracheal collapse is an upper airway condition which can sound much like kennel cough in that the coughing dog will likely be very well, with a harsh loud cough. It is caused by a weakness in the wall of the main airway (the trachea), and is often made worse by excitement, environmental irritants, or pulling on a lead. This is an anatomical abnormality see in small and toy breeds such as the Yorkshire terrier, and treatment in some cases requires the implantation of a stent within your dog's airway. Weight loss can be very beneficial in mild cases in obese patients.
Tumors within the chest can cause coughing if they impinge on the airways or cause fluid accumulation. The lungs are a common place for secondary tumors to arise from primary masses at other sites in the body.
Parasite Prevention Poll
Coughing as a Result of Heart Disease in Dogs
Cardiac coughing in dogs is usually caused by disease of either the heart muscle (cardiomyopathy) or the valves of the heart, which promote the normal flow of blood through the heart, preventing backflow and congestion. Dogs with a cardiac cough will often show other signs of poor circulation, such as exercise intolerance, fainting, or lethargy. Congestive heart failure is the result of blood pooling in the venous system and leakage of fluid into the lungs and body cavities, and as well as coughing, some dogs in congestive heart failure will have a swollen fluid-filled belly.
There are well known breed predispositions to these heart diseases; for example, Doberman Pinschers and Cocker Spaniels are prone to developing Dilated Cardiomyopathy (DCM), while smaller breeds, particularly Cavalier King Charles Spaniels are much more at risk of developing valvular disease.
Both classes of heart disease cause secondary changes in the chambers of the heart leading to heart enlargement. As well as the soft cough caused by fluid congestion in the lungs, this heart enlargement also causes a concurrent harsh cough as the larger chambers, especially the left atrium, compress and irritate the large airways, meaning the type of cough can vary in dogs with heart failure.
With advances in medical and surgical treatments heart disease in dogs has become a very treatable condition in many cases, and your veterinarian will discuss the most appropriate treatments for your pet.
Investigating Heart Disease With Ultrasound
Diagnosing The Cause Of Your Dog's Cough
As I've already stated above, unless your dog is very well in spite of his cough he should be brought to your veterinarian for examination. In some cases, your vet may be happy to make a diagnosis and prescribe treatment based only on his physical examination findings, but in some cases, for example in an older small breed dog with signs of both heart disease and chronic bronchitis, further testing is probably sensible to determine the best course of treatment.
Complete blood work does not usually provide a diagnosis, but can be important in ensuring any medications prescribed are not going to be harmful to your dog. For example, many older dogs with cardiac disease will also have some degree of kidney insufficiency, which requires great care in choosing the type and dose of medication used.
X-Rays of your dog's chest provide a great deal of useful information on the condition of the lungs and airways, as well as assessing the size, shape and position of the heart. Ultrasonography is a great non-invasive technique for examining soft tissue structures in the chest, but especially the heart, and allows a real time view of the movement and contractility of the cardiac chambers. Bronchoscopy is the insertion of a fibre optic cable down the airways. It needs to be performed under general anesthesia, which can obviously carry some risk, but it is the most useful way to examine the inside of the airways, and allows samples to be collected for bacterial and parasitic examinations, and can also help identify tumors within the lungs and bronchi.
What to Do If Your Dog Is Coughing
In most cases, a dog that has a persistent cough needs to be examined by a veterinarian. If you have a healthy young adult dog that has just recently started coughing, and is not showing other signs of illness, then you may be able to nurse him through it using steam vapor and home remedies as shown above. If you are in any way unsure about what to do, please ring your local surgery for advice.
Let me know in the comments below if there is any further advice you would like to see (non-urgent questions only).
This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.
Any Comments or Questions About Coughing Dogs?
mary on May 05, 2019:
my German shepherd has a cough like he has something stuck in his throat this just started last night should i be worried?
Ed Duke on January 06, 2019:
Our large (15-17 lb) Shitzu has been diagnosed with a tumor. He is on a small dosage of steroids. His worst coughing is in the mornings when he gets up. Except for the coughs he seems to be fine for his age of over 10 years. My concern is that he may be in pain whenever he is coughing. Can’t you explain what he is physically going through? I do not want him in any pain.
Patricia Gresham on August 21, 2018:
My Jack Russell, is coughing more at night
Alisa on July 02, 2018:
My medium golden doodle has had a cough since 5/15 and is on his third round of antibiotics. They tried an antihistamine with steroid at first and then gave him a cough suppressant for night time today which hasn’t stopped the cough.
They x rayed his lungs (weren’t concerned), tested for heart worm (negative) and today swabbed his throat to send off to lab. They also said his lungs didn’t sound as wheezy as two weeks ago.
When presssing on his tracheas he doesn’t cough. The cough usually occurs at night, when he gets up from sleeping or is excited and when pulling on his lead. It comes and goes worse some days than others. Any idea of what else to check?
Bruce King on March 03, 2018:
My Retriever-Labrador 35kg and in her 12th year had a very harsh dry cough about 5-6 times a day. She was put on anti-biotics for 2 weeks which helped, yet she still has the same type cough but only once or twice a day. Through this she remains in good shape loves to walk, is happy and shows no signs of slowing down her normal active ways. I'm prepared to have her x-rayed if necessary but it seems a bit premature to do considering cost. Would appreciate your advise. Thanks
Chris Barrett on August 06, 2017:
Hello and thank you for the above information. My 14 year old Maltese/Shihitsu has been on steroids and another tablet for two weeks, and, at the beginning of the treatment he seemed to respond positively to them, however with just a few days of medication left he hasn't improved and this cough and a sort of choking at the end of the process still persists. I have been quoted$500 for an X-ray which is out of the question on my disability pension (please note that I am NOT asking for money)
I AM asking if there is anywhere I can take him or if there is anything else you can suggest to help my little boy out.
Many thanks. Chris.
Lori on June 23, 2017:
I have a 10 week old Chihuahua puppy that seems absolutely fine, playful , nipping, and silly all day except when she goes to sleep she wakes up many times coughing and sounds like something is gg to come up but never does . What do u think I should do?
Miriam Baker on May 22, 2017:
My two year old Bichion is up to date on all his shots and then some..Even for kennel cough..
At times of stress... after a nice walk ... or for no reason he has a croupy cough .... It lasts a minute then it's gone until next time
Tracy on February 02, 2017:
Three years ago my Minx started coughing so I took her to the vet. After an exam and X-rays it was determined that she had Lymphoma. She lived 2 weeks after her diagnoses she passed away in my arms. The cough was her only sign at first then her lymph nodes started swelling and her health went downhill fast.
Laura on October 08, 2015:
My dog is 8 and has been coughing for two days when he gets excited, he is well, eats and drinks well and still wants to play. What could I give him to help this go away? Also we have had colds in the house but he only has a cough.
eirevet (author) from Ireland on April 07, 2015:
Thanks for your comment Diana. It's true that sometimes the old traditional remedies are every bit as effective as prescription meds, and the side effects can make the last few weeks or months of a pet's life less enjoyable. She was obviously well cared for to make it to fifteen years with ongoing breathing problems.
Diana L Pierce from Potter County, Pa. on April 06, 2015:
I had a fifteen year old Jack Russell terrier with a collapsed trachea a few years back. The best relief we had to offer her was honey. It worked better than the cough depressants the vet gave us. Sadly the illness took her life, but the honey helped make her last days more comfortable. This is a very informative hub. Voted up.