You may be familiar with the description of a cat "coughing up a hairball." While the physiology of bringing up a hairball is more in line with vomiting or regurgitation, cats do in fact cough. Why do they cough, though? What can you do to treat or prevent coughing in your cat?
Why Do Cats Cough?
Unlike dogs, who may struggle with coughing because of either a respiratory or a cardiac issue, coughing in cats is almost always caused by primary airway disease. While it’s not impossible for a coughing cat to be coughing primarily due to heart disease, more often than not a cat will be coughing because of a respiratory problem.
Any viral or bacterial respiratory infection can cause various respiratory symptoms. This can include not just coughing, but sneezing, and any nasal or ocular discharge as well. Two of the most common causes of viral respiratory infections in cats are feline herpesvirus and feline calicivirus. Bacterial infections can be caused by feline chlamydiosis, bordatella, or mycoplasma.
Affecting between only 1-5% of cats, feline asthma is not commonly diagnosed. It is believed that it is caused by a reaction to inhaled allergens. The adverse reaction of the cat’s immune system to the allergen causes inflammation, irritation, and even constriction of the airways. A cat with asthma may experience difficulty breathing (dyspnea), wheezing, rapid breathing, open-mouth breathing, and sometimes vomiting.
This is an infection within the lungs that inhibit their ability to both ventilate the cat as well as perfusion. Ventilating is the term for the lungs inflating and deflating, bringing in oxygen, and expiring carbon dioxide. Perfusion refers to the act of blood flowing through the lungs and exchanging carbon dioxide for oxygen. While there are two main types of pneumonia, aspiration and infectious, the result is the same. A cat with pneumonia will exhibit an increased respiratory rate, a fast heart rate, a fever, and colored nasal discharge. The infection and production of pus and mucous in the lungs can cause a cat to cough more in an effort to expel the pus and mucous from the lungs.
Heartworms are a type of parasite that are transmitted by mosquitoes. They can be found in wildlife such as coyotes and foxes but also in domestic pets like dogs and cats. Although heartworms can affect cats, the dog is the natural host of heartworms. This means that if a cat is exposed to heartworm larvae, it will be far less likely to mature into an adult worm than if it were a dog exposed. This also means that, while cats do in fact get heartworm disease, it is far less commonly seen in cats than dogs. In one study, adult heartworms were identified in 4% of cats tested as opposed to 28% of dogs tested. If a cat does have heartworms, they will develop something called Heartworm Associated Respiratory Disease (HARD). Cats with HARD may exhibit coughing as well as shortness of breath. They may also be lethargic, have a decreased appetite, and be experiencing weight loss.
This is a condition where fluid builds up in the pleural space, which is the space in the chest between the lungs and body wall. In cats, it can be caused by a variety of ailments such as infection, heart disease, or cancer. Regardless of the cause, a cat with pleural effusion may have coughing and increased respiratory rate and effort.
Diagnosing Coughing in Cats
Because coughing in cats can be caused by a wide array of things, the first diagnostic tool is a thorough history and examination. Your vet will want to know whether your cat is indoor only or if they go outside at all. They will want to know if they are on any heartworm prevention and if they are up to date on their vaccines. During the examination, your vet will listen to your cat’s lungs to see if they sound clear or if any crackles or wheezes are heard in the lungs. If your cat is also experiencing sneezing, conjunctivitis, or nasal congestion, your vet will likely be more suspicious of an upper respiratory disease process versus something affecting the lower airway. Radiographs of your cat’s lungs will give your vet an image of how clear or congested your cat’s lungs are. Blood tests can check for heartworm disease or evidence of infection.
If your cat’s coughing has been occurring chronically, over the course of a couple months or more, with no response to any treatments, they may need a test called a transtracheal wash. This is a specialized test that allows your vet to collect a sample of the cells in your cat’s upper airway to test for any bacterial or fungal pathogens or abnormal cells.
Treatment for coughing in cats will depend entirely on the cause. Steroids may be prescribed to treat any feline asthma. In severe cases, your vet may prescribe an inhaler (AeroKat) to deliver inhaled steroids. Cats with asthma should have triggers, such as cigarette smoke and potpourri removed from their environment. Antibiotics will treat any respiratory infections and pneumonia. Additional supportive care, such as oxygen supplementation and IV fluid therapy, may be needed depending on the severity of the pneumonia. While heartworm disease cannot be fully treated in cats, your vet can talk to you about supportive care to make them more comfortable as well as recommended preventions to prevent additional heartworms from being transmitted. In cases of pleural effusion, your cat will need the fluid drained to make them breathe more comfortably. Once this is done, additional diagnostics to determine what caused the pleural effusion can be performed.
How to Prevent Coughing in Cats
Heartworm disease is one of the few truly preventable cause of coughing in cats. Heartworm prevention should be given to cats monthly and year round to prevent heartworm disease. Vaccinating your cat for calicivirus can help prevent any infection caused by that specific pathogen. Asthma, infections, pneumonia, and pleural effusion can be more difficult to prevent. If your cat tends to gobble up their food and then regurgitate it back up because they ate too fast, this can predispose them to aspiration pneumonia. Puzzle feeders can help slow your cat down at meal times, preventing the regurgitation and thus preventing any risk of aspiration. The amino acid L-Lysine has immune support properties and is oftentimes recommended for cats prone to herpes flare ups. This can help prevent coughing from any infection. L-Lysine for cats is readily available over the counter in chews, powder, and gel form.
Coughing in cats can be caused by a variety of different illnesses. If you are concerned about your cat’s coughing, speak to your veterinarian.
Feline Asthma: What You Need to Know. Cornell University College of Veterinary Medicine, accessed 30 May, 2022.
Heartworm prevalence in dogs versus cats: Multiple diagnostic modalities provide new insights. Veterinary Parasitology. 2020;277:100027