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Common Causes of Pet Allergies

Cat and dog dander, or skin flakes, as well as their saliva and urine, can cause an allergic reaction – sneezing, wheezing, and running eyes and nose. Both feathers and the droppings from birds, another common kind of pets, can increase the allergen exposure. Bird droppings can also be a source of bacteria, dust, fungi and mold. This also applies to the droppings of other caged pets, such as gerbils, hamsters and mice.

The animal hair is not considered to be a very significant allergen, however, the hair or fur can collect pollen, dust, mold, and other allergens. Although individual pets may produce more or less allergen, there is no relationship between the pet's hair length and allergen production. There is also no such thing as a non-allergenic breed.

Animal allergens are found mostly in homes where pets are present. What is surprising, however, is that these allergens are also found (in lesser amounts) in places where pets have never been present, such as schools, workplaces, and other public spaces. Since dander allergens are sticky, they can be brought to these places on the clothing of pet owners. Also, while dander on a smooth surface (such as a wall) can be easily wiped off, in soft materials, such as carpets, mattresses, upholstered furniture, and clothing, it can persist for long periods of time. That is why, unless special steps are taken, pet dander can remain in a home for up to six months after the pet has been removed.

People who love pets and don't have allergies should not become complacent. "You can develop an allergy at any time," states Derek K. Johnson, MD, director of allergy and immunology at Temple University Children's Medical Center. "That's why it's important to know what causes pet allergies. It's the flakes from the animal's skin, called dander, not the fur. So even if it's a bald cat, you can be allergic."

Cat allergy

Dog allergy

Other pets