Feline Asthma and Wheezing

Feline Asthma is a chronic respiratory disease characterized by sudden episodes of breathing difficulty. Episodes are most often triggered by allergies or stress, which cause constriction of the airways. This leads to breathing difficulty, coughing and wheezing. A low-grade, chronic cough may be the only sign but an acute crisis can occur at any time that is potentially a life-threatening event. Affected cats are usually between 2 and 8 years of age. Siamese breeds and females may be more susceptible.

CAUSES
The most common causes are allergies to inhaled substances called allergens in the environment. Pollen, mold, and dust are incriminated outside. Tobacco smoke, perfumes, dusty cat litter, and powdered carpet deodorizers are the most common culprits inside. Other causes include stress, i.e., new pet moves into home as well as lung parasites including lungworms and heartworms. Bacterial infections often complicate these cases; secondary bacterial pneumonias are not uncommon in asthmatic cats or people.

SIGNS
1. Hairball-like coughing often with difficulty breathing. This hairball cough does not bring up any hairballs.
2. Wheezing.
3. Shortness of breath.
4. Breathing may be slow and deliberate, too fast and shallow.
5. Cats may breathe with their mouth open to help move air through their lungs. Cats normally breathe with a closed mouth.

DIAGNOSIS
Diagnosis is confirmed by chest x-rays, which allow differentiation from other diseases with similar signs, such as Bronchitis, Heartworm Disease, and Pneumonia. Fluid and mucous samples from the airway may be collected and microscopically examined to help pinpoint the exact cause.

TREATMENT
True asthma usually responds quickly to a combination of medications geared to open the airway and block the allergic reaction. Severe cases often also require oxygen therapy. Antibiotics are indicated if bacterial infections such as Pneumonia are present.

In an emergency:
* An injection of Epinephrine (adrenalin) reverses an asthmatic crisis in 15 minutes.
* Terbutaline is an airway dilator – when given by injection, it will open airways within 30 minutes.
* Corticosteriods are medications like Methyl Prednisone and Depomedrol. They act within 48 hours of injection and last 10 to 14 days. This is a viable alternative for some owners, unable to give pills to their cat. Cats, unlike humans, are relatively resistant to the side effects of steroids; therefore this is suitable for long-term management in certain cases.

LONG TERM MANAGEMENT OF ASTHMA

Long-term management of Asthma involves:
1. Removing allergens from environment
a. Use an air purifier, electrostatic air filter.
b. Use dust free, scent free cat litter.
c. Avoid odor-controlling sprays.
d. Reduce stress, don’t smoke.
2. Various medications are used to open the airways (Bronchodilators) and decrease the allergic reaction (Corticosteroids) similar to those used for Human Asthma.
a. Airway Dilators include:
i. Terbutaline (Brethine), and
ii. Theophylline (Theo-dur).
These medications decrease airway constriction and allow air to pass in and out of the lungs more easily. Terbutaline is available as an inhalant for humans and certain vets have devised methods to use this as an inhalant for cats.
b. Cyproheptadine is a medication that decreases the chemical serotonin, which has been shown to be involved in airway constriction. It is often used along with steroids and/or in cats unable to take steroids. Side effects include increased appetite and sedation.
c. Zamflurkast (Accolate) – This is a new human asthma medication used to decrease the dose of steroids necessary to manage asthma. In cats, this is considered experimental but initial reports have been good.
d. Cyclosporine – A – This medication is used in human organ transplant patients to modulate the immune response and is quite expensive. Recently, trials have been used in feline asthmatic cases unresponsive to other therapies.
e. Anti-Interleukin-5 Antibody is an anti-cancer medication still in the experimental stages for use in asthmatic felines.

COMPLEMENTARY TREATMENTS

Principles include treating allergies if present, decreasing airway inflammation and reducing environmental stress.
* Hypoallergenic Diets may relieve asthmatic signs associated with dietary allergies.
* Fish Oil: Flaxseed Oil.
* Antioxidants: Vitamins C & E
* Vitamin B6
* Vitamin B12
* Acupuncture has been effective in certain cases.