A cat suffering from asthma will noticeably struggle for breath. They will stop moving, breathe with their mouths open, and you may see their sides move in and out as they struggle for air. They may also have congestion in their lungs and cough up mucus. You may hear them wheeze when breathing. If the asthma is severe, the cat's gums and other mucus membranes may turn blue from lack of oxygen. As with asthma in humans, these symptoms will come and go. Cats will have an asthma attack and then may seem fine once the attack is over.

 

Allergies and Asthma
Asthma caused by allergies is most common in cats versus other pets reports The Merck/Merial Manual for Pet Health.  This is usually a seasonal condition and more severe in the summer and when cats spend more time outside. When exposed to an allergen, the histamines released cause the lungs and airways to constrict, making it difficult for the cat to breathe.

Chronic Asthma

Cats with chronic asthma will have asthma year round. In chronic asthma, more than just allergies will trigger an attack. Exercise and stress may trigger an attack. Sometimes cats with chronic asthma may struggle to breathe for no apparent reason. Usually cats are born with this condition and symptoms start when they are kittens or as young cats. It's most common in Oriental breeds, such as Siamese and Himalayan cats, and may be hereditary. It's rare for an older adult cat to suddenly develop chronic asthma.

Diagnosing Asthma in Cats 

Seasonal asthma due to allergies can be easier to diagnosed just based on symptoms. If the cat has reduced or no symptoms during the winter or when kept indoors, then a diagnosis can be made clinically. However, for symptoms that do not easily resolve and occur year-round, the veterinarian will need to perform more tests to determine the cause of a cat's breathing problems. This may include x-rays, cultures of mucus, and viewing the airways and lungs with an endoscope.  

Treating Asthma in Cats

If the cause of a cat's asthma is allergies, then avoiding the allergy is the best prevention. This may mean keeping your cat indoors. If this does not resolve the symptoms, then your veterinarian may prescribe a corticosteroid, such as prednisone, and/or inhalers similar to medications used in humans that help open the airways. For severe acute attacks, cats may need emergency treatment at the veterinarian's office.

If your cat has been diagnosed with asthma, know that it can be managed and your cat can live a long, active life. However, you will need to learn to manage your cat's condition with your veterinarian's help. Ask your vet how to best prevent asthma attacks and how to best treat asthma attacks when they do occur. Also, ask your vet how to determine if you can treat the asthma attack at home or if you should bring your cat in for emergency veterinary care.