The patient can take an active role in managing the environment at home and in the office. In allergic patients, avoiding offending allergen(s) may drastically reduce the frequency of asthmatic attacks. Allergens can be identified through a history of reaction and skin or blood testing. Common allergens are dust mites, mold spores, animal dander, and plant pollens. Insects such as the cockroach may also produce allergens that precipitate attacks. Specific allergens may be identified through testing of samples taken from the home.

Dust Mites

Dust mites may play a significant role in many asthmatic attacks. These extremely small insects depend on moisture for survival and live on human skin dander. They have been found in abundant quantities in mattresses, pillows, clothes, bed coverings, carpets, towels, and even stuffed animals. In the home, the highest concentrations have been found in the bedroom. It is the feces of the dust mite that produces an allergic reaction.

Because these droppings are airborne when dust is disturbed, they can be inhaled and cause allergic reactions. The particles are large enough to be trapped, however, and the patient can significantly reduce the number of dust mites through specific measures.

These measures include trapping dust mites by using a zippered mattress and pillow cover. Sheets and bed covers should be washed weekly in hot water. Carpeting should be removed wherever possible and remaining carpeting treated with a chemical agent (acaracide) such as benzyl benzoate (Acarosan) or tannic acid that kills mites Vacuuming is important and should be done once a week, preferably not by the asthma patient. If you must vacuum yourself, use a dust mask and a vacuum cleaner with high-density paper bags and filtration as well as a HEPA (High Efficiency Particulate Air) filter. Indoor humidity levels should be reduced to less than 50 percent with a dehumidifier.

An air filter may be helpful in reducing allergen levels for the dust mite as well as other offending substances. Air filters may be mechanical or electrical. One of the best mechanical types incorporates a HEPA filter. These come in various sizes according to the volume of the room (amount of air) that has to be filtered and circulated. Know the dimensions of the room in which the air filter will be placed before you purchase one. One example of an electrical filter is the electrostatic precipitator. These filters and the HEPA filter can be placed in a central forced air system in the home. Electrical filters require more frequent cleaning than mechanical types.