Why is my dog or cat coughing?
This is a question that many pet owners ask their veterinarians. It's a good question because a cough can mean many things. Generally speaking, a cough results from an irritation of the respiratory system. The respiratory system includes the opening to the outside world (mouth or nose), nasal passages, pharynx (throat), larynx (voice box), trachea, bronchi, and the small airways of the lung. Additionally, coughing can be related to problems with the heart or a mass in the chest. Because a cough can be a symptom of many different diseases, it is important that all coughing pets be seen by their veterinarian. Here are some questions that your veterinarian may ask.
Is it really a cough?
A cough is a forceful expulsion of air from the lungs through the airways and an open mouth. Surprisingly, what sounds like a cough may be something else. Coughing has been confused with gagging, wheezing, labored breathing, retching, vomiting, and a condition known as reverse sneezing. It's very important that the sound coming from your dog or cat is properly identified. Coughing and all of the conditions listed above have different causes.
What does the cough sound like?
The sound produced by a cough can indicate its cause. A hacking, honking, brassy cough is generally associated with diseases of the large airways; trachea and/or large bronchi. In small/toy breed dogs tracheal collapse is a common condition. Tracheal collapse produces a characteristic "goose-honking" sound. Tracheal trauma from a collar, for instance, can also cause a honking cough. Subtle half-hearted coughing could be a sign of pulmonary edema (fluid in the lungs). A cough that sounds moist may indicate an infection of the lungs or congestive heart failure.
When does your animal cough?
What time of day or night and under what circumstances your dog or cat coughs can help determine the cause. If the cough is a result of early heart disease then the cough will be more common at night. However, as heart disease progresses, this cough may occur at any time. With chronic bronchitis, exercise may induce a cough. When pressure is put on the animal's collar a cough may be stimulated. It is important to note when and under what conditions your animal coughs.
Is the cough productive or non-productive?
In a productive cough, something is "coughed up", such as a watery fluid, pus, or blood. This should not be confused with vomiting. Vomiting will contain stomach contents and bile. A productive cough is most often associated with an infectious process (bacterial, viral, or fungal). Allergic lung disease or early heart disease would produce a non-productive cough. Non-productive coughing produces sound but no discharge.
How long has your animal been coughing?
Generally speaking, if your dog or cat has been coughing for more than five days he should be seen by your veterinarian. However, if your pet has a cough and is obviously very ill, seek veterinary help as soon as possible.
Diagnosis: Determining the cause of the cough
Using information gathered from the above questions, along with a thorough physical exam, your veterinarian will begin to get a better understanding of what is causing your pet's cough. The veterinarian may also request some diagnostic tests to help discover the cause of your pet's cough. These include:
Additional tests might include:
Trans-tracheal wash: a procedure in which a catheter is placed through the skin and into the trachea. The catheter is passed to where the trachea branches into bronchi. A sterile fluid is placed or "washed" into the area and then recovered for examination.
Laryngoscopy or bronchoscopy: procedures that allow direct visualization of the airway using a bronchoscope (flexible tube with optical fibers) device that travels through the mouth and into the trachea and bronchi.
Bronchoalveolar lavage: a bronchoscope is passed through the trachea and into the bronchi and cells and fluid from deeper in the lung are collected for examination.
Fine-needle aspirate: a procedure in which a small diameter needle is inserted into the diseased portion of the lung and cells are recovered for examination.
Feline leukemia testing in cats.
The more common causes of coughing in dogs and cats are shown in the table below. (This chart is not meant to be an inclusive list.)
(Less common in cats)
|Productive cough, with or without labored breathing, Fever, Loss of appetite, Severe illness
||Thoracic radiographs, CBC, Transtracheal wash, Broncho-alveolar lavage, Bronchoscopic exam, Fine needle aspirate
||Antibiotics, Supportive care
||Depends on the type of bacteria and the extent of the illness
|Productive cough, Fever, with or without dyspnea, Often complicated by a bacterial infection
CBC, Transtracheal wash, Broncho-alveolar lavage, Bronchoscopic exam,
Fine needle aspirate
||Supportive care, Antibiotics (if needed for secondary bacterial infection)
||Depends on the virus involved and the extent of damage done by the secondary infection
Roundworms (dog & cat)
|Non-productive cough, with or without labored breathing
Blood test for heartworm, Fecal exam
||Anti-parasiticides, Supportive care
||If diagnosed early prognosis is good
|Cough, sometimes productive, with or without labored breathing
CBC, Transtracheal wash, Broncho-alveolar lavage, Bronchoscopic exam, Fine needle aspirate
||Antifungal agents, Supportive care
||Depends on extent and length of infection
(May be in lung or chest)
|Lymphoma (dog & cat),
|Non-productive cough, with or without labored breathing
||Thoracic radiographs, Fine needle aspirate
||Surgery, Chemotherapy, Radiation Therapy
||Depends on the site, nature of the tumor, and how invasive it is
||Congestive Heart failure
||Subtle "half-hearted cough," most often at night - progressing to anytime, Cough may be moist and productive as disease progresses
Heart auscultation, Electro-cardiogram, Blood chemistry profile,
Blood parasite screen
||Surgery to correct leaky valve or other abnormalities, Medications to lower load on heart +/or increase the strength of the heartbeat
||Depends on the specific heart condition
|Allergic or Irritant
(Air-borne allergen such as dust or pollen)
Second hand smoke
||Thoracic radiographs, Symptomatic response to allergen, Allergy testing
||Depends on environmental controls and reducing the allergen exposure
||Tracheal trauma from excessive pressure on a collar,
Irritation from barking
|Honking cough when pressure is placed on collar
||Based on symptoms
||Remove trauma, Anti-inflammatory medications, Use of halter instead of collar
||Depends on the extent of the trauma
Lung lobe torsion,
|"Goose-honking" cough (tracheal collapse), Productive cough (trying to expel the foreign body)
|Bronchodilators, Cough suppressants, Limited activity, Use of halter instead of collar,
Surgically removing the foreign body
||Collapsing trachea: fair with maintenance program. Depends on damage done by the foreign body
The treatment of cough
Treatment of the cough will depend solely on its cause. For example, bacterial pneumonia with a cough will require antibiotics along with other supportive care. A mass in the chest will require either surgery, chemotherapy, radiation therapy or a combination of all three. Resolving a cough caused by heart disease would involve therapy to correct or strengthen the heart. If your dog or cat has a productive cough, it is very important that we do not suppress the cough. Additionally, human cough suppressants should never be given to your pet as they may be toxic. Alternatively a cough suppressant prescribed by your veterinarian could be used on a nuisance cough that is non-productive.
Any cough that your pet displays is cause for concern. As illustrated above, a cough could be a self-limiting nuisance or a sign of a serious illness. To prevent conditions that cause couging, a good preventive health plan is necessary. As always, you should have your pet on a quality diet appropriate for the animal's age, he should be current on all appropriate vaccinations, and be on a parasite control program that includes preventives for heartworms and intestinal worms. It is also very important that you have an established relationship with a veterinarian.