Cat Allergies, Hives, Itchy Skin, and Asthma

Cats are beloved family members of millions of Americans. Unfortunately, these pets are also allergen factories for as many as 25 percent of the population, according to the American College of Allergy, Asthma and Immunology.

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As many as 29 percent of asthma cases could be linked to cat allergens.

Journal of Allergy and Clinical Immunology, a 2007 study

Understanding Cat Allergies

It is a common misconception that cat fur is the cause of cat allergies, but the primary culprit is a protein called “Fel d 1,” which is excreted through cat skin and cat saliva and spread over their bodies when they clean themselves. Pet saliva can get in a lot more places than you might think -- it can cling to bedding, carpets, furniture, and even clothing.

Allergens are also found in the hair and skin cells (dander) that cats shed. Dander is small and can remain airborne for long periods of time, making it easily inhaled. It can also collect on fabrics and in clothing.

Pet allergy symptoms typically develop in and around your nasal passages after you have inhaled the allergen. They include:

• Red, watering, itching eyes • Swollen, discolored skin under the eyes • Runny, stuffy, itchy nose • Sneezing • Itchy throat • Coughing • Postnasal drip • Pain and pressure in the sinuses • Poor sleep (as a result of uncomfortable symptoms)

Cat Allergies and Hives

In addition to nasal symptoms, some people also may show signs of allergic contact dermatitis, an immune system reaction that causes skin inflammation, redness, and irritation.

When an allergic person comes into contact with cat saliva or dander, the immune system reacts to protect the body by releasing histamines, which are chemicals the body produces to fight off foreign invaders. The resulting hives or raised, itchy red patches on the skin are a direct result of the allergen eliciting a local immune response.

Cat Allergies and Asthma

As many as 29 percent of asthma cases could be linked to cat allergens, according to a 2007 study published in the Journal of Allergy and Clinical Immunology.

If you are in this group, you may find that cat allergens can:

• Make it more difficult to breathe • Cause pain or tightness in the chest • Produce a wheezy or whistling sound when breathing • Cause coughing • Interfere with sleep

Dealing with Cat Allergies

If you know you are allergic, the best thing you can do for your health is to avoid cat allergens. This will not cure your allergy, but it can cut down on unpleasant symptoms and asthma attacks significantly. Your physician or allergist also can prescribe medications that can help you control symptoms when you cannot avoid cat allergens. Some treatment options suggested by the Mayo Clinic are:

• Antihistamines to help control your immune response to allergens • Decongestants to decrease nasal inflammation • Corticosteroids to control inflammation • Cromolyn sodium, a nasal spray that prevents the release of histamines • Leukotriene modifiers, which inhibit the production of chemicals that cause tightening of airways and excess mucus production

You can also discuss allergy shots or immunotherapy with your doctor. This type of treatment involves a series of injections of small amounts of cat allergen, which may desensitize your immune system response and relieve your symptoms. Be sure to discuss all treatment options and potential side effects with your doctor.

About the Author

Boyan Hadjiev, MD, has been a practicing physician for five years. He is double board certified in Internal Medicine, (2003), and Allergy and Immunology, (2005).

Dr. Hadjiev graduated from University of Michigan with a BA in biology and an MD from Cleveland Clinic-Case Western Reserve School of Medicine.