Feline Asthma

Allergic bronchitis or asthma is an inflammatory reaction in the lower airways. When an allergen, like dust mites, is inhaled it starts an allergic reaction that results in changes in the

airways.

Some common allergens include dust, smoke, household chemicals, mildew, molds, weeds, pollens and cat litter. When these allergens enter the airways, they cause an increase in mucous production, and constriction of airways. At home, owners may notice that their cat is breathing more rapidly or there is abdominal movement associated with breathing, or their cat could also be coughing. On physical exam, veterinarians may additionally note wheezes and rattles when listening to a cat’s lungs.

Chest radiographs are one of the first tools that veterinarians will use to diagnose asthma.

Changes on chest radiographs can include thickening of airway walls and flattening of the diaphragm from lung over inflation. However, about 25 % of cats with asthma can have normal chest radiographs, so a second tool to help diagnose asthma is called broncho-alveolar lavage (BAL). During this test a small amount of sterile saline is washed into the airways, then recovered for cytologic evaluation. The cells collected from an asthmatic lung will have more white blood cells, especially eosinophils- a result of inflammation in the cat’s lungs. Sometimes a therapeutic trial will be used to help diagnose asthma. Like humans, steroids can be used in cats to help manage asthma. A short course of oral steroids can be prescribed with an expected reduction in coughing and respiratory rate/effort in asthmatic cats.

Several strategies can be used for long term management of feline asthma. First, working to reduce airway allergens can be very helpful. This can be achieved by avoiding smoking in the house or the use of air fresheners, removing carpets that can harbor dust mites, frequent vacuuming to reduce dust and pollen as well as humidifying the air. As mentioned above, steroids are also commonly used to treat asthma and are very effective at reducing airway inflammation. The steroid can be administered by mouth, through an inhaler or in an emergency, by injection. Treatment often starts with oral steroids (prednisolone) as they act very quickly, but inhaled steroids are safer for long term treatment- this allows for a lower level of systemic steroids thereby reducing the risk of side effects, but providing a concentrated dose at the site of inflammation- the lungs. To administer inhaled steroids, a cat must be trained to use a special fitting cat mask.

In some cases, feline asthma can progress to a respiratory emergency. If your cat is breathing with their mouth open and has abdominal movement in conjunction with breathing contact your veterinarian immediately.