Coughing in Dogs: Causes and Treatments
Coughing is a reflex initiated by an irritation in the airway. Coughs are caused by respiratory infections, congestive heart failure, chronic bronchitis, respiratory tract tumors, collapsing trachea, pressure from tight collars, and inhaled irritants such as grass seeds, fumes, and food particles.
The type of cough often suggests the diagnosis:
The diagnostic workup of a dog with a chronic cough includes a chest X-ray and transtracheal washings. Washings are cells obtained by flushing the trachea with saline solution. This can be done with a sterile tube passed down the trachea while the dog is sedated, or by direct penetration of the trachea through the skin of the neck using a needle and catheter. The washings are processed for cytology and bacterial culture. The information usually leads to a specific diagnosis.
Bronchoscopy is particularly useful in the investigation of chronic coughs and coughs with the production of mucus and blood. The procedure requires sedation or general anesthesia. A rigid or flexible endoscope is passed into the trachea and bronchi. This enables the veterinarian to see the interior of the respiratory tract. Biopsies can be taken with accuracy, and washings collected for examination and culture. Bronchoscopy is also the procedure of choice for removing bronchial foreign bodies.
Treating a Cough
Only minor coughs of brief duration should be treated at home. Coughs accompanied by labored breathing, a discharge from the eyes or nose, or the production of bloody sputum should be seen and treated by a veterinarian.
It is important to identify and correct any contributing factors. Eliminate any irritating atmospheric pollutants, such as cigarette smoke, aerosol insecticides, strong cleaners, house dust, and perfumes, from the home environment.
Cough suppressants should be used selectively and only for short periods. Although they decrease the frequency and severity of the cough, they do not treat the condition causing it. Overuse may delay diagnosis and treatment. Cough suppressants (but not expectorants) should be avoided in dogs with bacterial infections and when phlegm is being brought up or swallowed. In these cases, productive coughs are clearing unwanted material from the airway.
Dogs with a dry cough can be helped by keeping them in the bathroom while you shower and not using the fan. The added moisture may loosen secretions. Using a humidifier can also be helpful.
Foreign Body in the Lungs
Grass seeds and food particles are the most common foreign materials inhaled by dogs that are big enough to lodge in the smaller breathing tubes. Most of these are quickly coughed up. If the object becomes fixed in the airway, it causes intense irritation and swelling of the air passage. Mucus collects below the obstruction and forms an ideal medium for bacterial growth and infection. Objects that remain in the lungs for several weeks can cause pneumonia.
Sudden attacks of coughing that occur immediately after vomiting or after a dog has been running in tall grass and weeds suggest inhalation of a foreign body. Lungworms in the bronchi also cause severe coughing spasms.
Treatment: Unexplained coughing should be investigated by a veterinarian. Avoid cough medicines, unless prescribed by your veterinarian, since they delay treatment. Bronchoscopy is usually successful in locating and removing bronchial foreign bodies, particularly if the procedure is done within two weeks of inhalation.