Feline Asthma

by Susan Little DVM, Diplomate ABVP (Feline)
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Feline asthma has been called by many other names, including chronic bronchitis, bronchial asthma, and allergic bronchitis. Regardless of the name, it is a common feline ailment. Inhaled allergens cause sudden contraction of the smooth muscles around airways, leading to typical clinical symptoms. It is usually impossible to determine which allergens cause asthma in individual cats, but common ones include grass and tree pollens, cigarette or fireplace smoke, various sprays (hair sprays, deodorants, flea sprays, deodorizers), and dust from cat litter.

Feline asthma is found in all areas of the world and in cats of all ages. The prevalence in the general adult cat population is about 1%. The most common symptoms in cats with asthma are wheezing and coughing. The coughing has been described as a dry, hacking cough that could be confused with gagging or retching. Many cats are misdiagnosed as having hairballs! Paroxysms of coughing occur frequently. In mildly affected cats, coughing and wheezing may occur only occasionally. A few cats with asthma are asymptomatic in between acute and severe bouts of airway constriction. The most severely affected cats have daily coughing and wheezing and many bouts of airway constriction, leading to open-mouth breathing and panting that can be life threatening.

The symptoms of asthma can mimic other diseases, such as heartworm, pneumonia and congestive heart failure. A diagnosis is reached by using chest x-rays, a complete blood count, a feline heartworm test, and a techniques to sample cells from the lower airways (transtracheal wash, bronchial wash, or bronchoalveolar lavage). Chest x-rays may be normal in some cats with asthma, while others will have signs of bronchial inflammation, collapse of the right middle lung lobe, and over inflation of the lungs.

Unfortunately, feline asthma is a chronic progressive disease that cannot be fully cured. Medications can reduce the symptoms of asthma a great deal, but may not be able to eliminate coughing fully. In recent years, veterinarians have found that the most effective therapy for feline asthma may be to use inhalers such as human asthmatics use. A mask and spacer system, called AeroKat®, has been invented to enable cats to use inhalers or puffers. This system is similar to the mask and spacer system used to treat babies and small children.

The most important type of drug for treating feline asthma is a corticosteroid to reduce the chronic inflammation. The most commonly prescribed corticosteroid inhaler is Flovent®. Some feline patients also benefit from another type of medication called a bronchodilator. Bronchodilators help open the airway at times of severe coughing or wheezing. One common bronchodilator inhaler used for humans and cats is Apo-Salvent®.

Some feline asthmatics may be given oral medication. This may be necessary if the patient does not respond well to inhaler therapy alone, but the amount of oral medication given is usually less than if the cat was not on inhaler therapy at all. Many patients that started asthma therapy a few years or more ago will be only on oral therapy, usually a corticosteroid such as prednisone. While oral therapy may be less expensive than inhaler therapy, it is suspected that inhaler therapy can do a better job and is associated with fewer long-term side effects. Regardless of the type of medication used, it is important to notify your veterinarian if there is any change in your cat's condition while on asthma medication.

Some actions can be taken in the home to reduce the symptoms of feline asthma. Avoiding smoke from fireplaces and cigarettes is very important. This type of smoke tends to settle near the floor in a room at the cat's breathing level. Reducing the use of air fresheners and other household sprays can also be effective. Use human grooming products that are in spray form, such as hair sprays or deodorants, well away from the affected cat. Change to a low-dust clay cat litter or one that is made of an alternate material. Air purifiers may also be helpful. Any activity that is associated with symptoms of asthma in the individual cat, such as going outside in cold weather, should be avoided. Finally, obese cats will benefit from weight reduction.