All warm-blooded animals -- including pets and uninvited rodents -- produce dander that could trigger asthma in children who have become sensitive to it.

Dander is the materials shed from the animals' bodies, which may include bits of feathers, hair, or dried skin. It's sometimes affectionately called "pet pollen." Bits of feces or saliva can also trigger inflammation.

Step One

Determine if there is an allergy to one or more indoor animals where the child spends much time. Timing of nose, eye, or chest symptoms may provide some clues:

• Do they get worse during or just after vacuuming carpets?
• Do they get better when away from the home or school with the indoor animals for a week or longer?
• Do they get worse in the first 24 hours of returning to the home or school?

The best way to tell if animal dander is a problem is by allergy testing. Children with persistent asthma who are regularly exposed to indoor warm-blooded animals should have allergy skin testing and/or blood tests.

Step Two

Decreasing exposure to animals that someone is sensitive to can greatly improve their asthma. Removing the animals from the child's home has the biggest effect, but this is not always practical. There are other ways to help:

• Keep the animals out of the child's bedroom
• Keep the bedroom door closed whenever possible.
• Decrease carpeting and upholstered furniture, and decrease contact by the pet with these items.
• Use HEPA air filters.

Weekly washing can greatly reduce the dander from some pets.