Feline "asthma" is a bronchial disease similar to asthma in people.

Coughing and/or wheezing are common clinical signs of this disease.

Diagnosis is made on testing of secretions from the lungs.

Treatment is life long and involves the administration of medications.

What is Feline Asthma?

• Feline "asthma" is a bronchial disease similar to asthma in people.
• This respiratory condition is common in cats and can cause signs such as chronic coughing, wheezing, and loud or rapid breathing.
• In severe cases, life-threatening respiratory distress may occur. This disease is caused by inflammation (irritation) in the lungs in response to irritants or allergens in the environment. The cells in the lung respond to the insult by increasing the production of mucus and inducing constriction (narrowing) of small airways; these responses lead to the clinical signs observed in cats with asthma.
• In most cats, the cause of disease is unrecognized, but exposure to smoke-contaminated rooms, aerosol sprays or cleaners, and dusty or perfumed litter as well as recent upper respiratory infection with should be considered as possible triggering events.

Clinical Signs

• Bronchial disease can affect any age of cat, and the most common symptoms include the following:
  
  • Coughing - episodes of coughing can resemble vomiting or may be confused with the attempted expectoration of a hairball
    
  • Loud breathing sounds or wheezing noises
    
  • Rapid breathing and/or panting
    
  • The disease can also induce emergency situations characterized by acute respiratory distress and open mouth breathing. This type of situation can be seen in cats that are already treated for asthma or as a first sign of the presence of the disease, and requires immediate medical intervention.

Diagnosis

• A thorough history of the clinical signs is very important for your veterinarian. On physical examination, the lung sounds are usually harsh or wheezy in cats with bronchial disease. Additional tests are usually required to determine the cause of respiratory problems, to assess the severity of disease, and to decide on specific therapy.
• These diagnostic tests may include the following:
  
  • Basic blood and urine tests, to evaluate general health.
    
  • More specific blood tests can rule out primary infections that could trigger airway inflammation and to rule out other conditions that might mimic asthma.
    
  • In some areas of the country, heartworm disease must be investigated through use of blood tests or echocardiograph.
    
  • Lungworm infection in cats can also mimic asthma, and a specific stool test on fresh, unrefrigerated feces must be performed to diagnose this condition.
    
  • Chest x-rays in cats with asthma or bronchitis often show thickened airway walls but they can appear normal even in a severely affected cat.
    
  • Collection of fluid from within the airways with a tracheal wash may also be useful. Your veterinarian may elect to anesthetize your cat briefly, place a tube into the airways, and inject a small volume of fluid into the lungs to "wash" cells from the airways. This fluid can be evaluated for the presence of bacteria or parasites that might trigger airway inflammation, and for the type of cells present.

Treatment

• When infectious or parasitic causes of cough have been ruled out or diagnosed and treated, treatment with steroids (prednisone or prednisolone) is generally employed for treatment of asthma or bronchitis. The side effects associated with steroids in cats are generally minimal. A high dose is used at the beginning, and the dosage is gradually decreased over the following weeks to months. It is important to keep in contact with your veterinarian regarding your cat's response to medication, because every animal requires a different type or amount of drug. In some cats, the medication can be eventually stopped, but many require some amount of steroid daily or every other day for the rest of their life.
• In cats that cannot be given pills by mouth, use of inhaled medications (steroids and bronchodilators) can be extremely helpful in controlling disease.
• Metered-dose inhalers (MDIs) designed for asthma treatment in human medicine can be used in cats, and administration of the aerosol medication is done with a dispensing chamber and facemask. MDIs contain medication and propellant within a small steel canister and plastic shield. The MDI must be well shaken prior to use. Pressing onto the top of the MDI actuates the propellant, resulting in release of a fast-moving spray of medication. To transmit the medication into the lungs of the cat, the MDI must be actuated into a pediatric spacer attached to a facemask. With the facemask enclosing the lips and nose of the cat, one puff of drug is administered, and the cat inhales 8 to 10 breaths to pull the medicine into the lungs. Medication may be required 1 to 4 times per day, and in cats with severe clinical signs, use of oral medication may also be required for the first several weeks of treatment.
  Although this method is more expensive than oral treatment, it can provide excellent control of symptoms. MDI is likely the best method of treatment for a cat that should not receive oral or injectable steroids, such as the cat with diabetes, or when regular pill administration is not possible.

Mask-Aerochamber MDI	How to administer the aerosol drugs with the aerochamber and MDI