Lifestyle Changes:

People with existing allergies should avoid irritants or allergens. These triggers include:

• Pollen. This is the primary cause of allergic rhinitis.
• Dust mites, specifically mite feces, which are coated with enzymes that contain a powerful allergen. These are the primary allergens inside the home.
• Animal dander (flakes of skin) and hair from cats, house mice, and dogs. House mice are proving to be significant sources of allergens, particularly in urban children.
• Molds.
• Fungi.
• Cockroaches are major asthma triggers and may reduce lung function even in people without a history of asthma.
• Some studies suggest that early exposure to some of these allergens, including dust mites and pets, may actually prevent allergies from developing in children.

Indoor Protection against Allergens

Controlling Pets. People who already have pets and are not allergic to them are probably at low risk for developing such allergies later on. When children are exposed to more than one dog or cat during their first year, they have a much lower risk for not only pet allergies but also seasonal allergies and asthma. (Pet exposure does not protect them from other allergens, notably dust mites and cockroaches).

For children who have an existing allergy to pets:

• If possible, pets should be given away or kept outside.
• If this isn't possible, they should at least be confined to carpet-free areas outside the bedroom. Cats harbor significant allergens, which can even be carried on clothing. Dogs usually present fewer problems.
• Washing animals once a week can reduce allergens. Dry shampoos, such as Allerpet, that remove allergens from skin and fur and are now available for both cats and dogs and are easier to use than wet shampoos.

Preventing Exposure to Cigarette and Cooking Smoke. Parents who smoke should quit. Studies show that exposure to second-hand smoke in the home increases the risk for asthma and asthma-related emergency room visits in children. [For help in quitting, see In-Depth Report # 41: Smoking.]

Controlling Dust. Spray furniture polish is very effective for reducing both dust and allergens. Air cleaners, filters for air conditioners, and vacuum cleaners with High Efficiency Particulate Air (HEPA) filters can help remove particles and small allergens found indoors. Neither vacuuming nor the use of anti-mite carpet shampoo, however, is effective in removing mites in house dust. Vacuuming actually stirs up both mites and cat allergens. People with these types of allergies should avoid having carpets or rugs in their homes. For children with allergies, vacuuming should be performed when the child is not around.

Bedding and Curtains.

• Replace curtains with shades or blinds, and wash bedding using the highest temperature setting.
• Encase mattress and pillow in special dust mite proof covers (however, washing is very important since impermeable covers alone do not help prevent allergies).
• Wash pillow in water hotter than 150° F, or in cooler water with detergent and bleach.
• Wash sheets in blankets weekly and hot water.
• Avoid sleeping or lying on cushions or furniture that is cloth covered.
• Stuffed toys should be kept away from the bed and washed weekly as described above. Placing toys in a dryer or freezer may help but is not considered enough.
• Children should sleep as high off the floor as possible (avoid the bottom bunk of a bunk bed).

Reducing Humidity in the House. Living in a damp environment is counterproductive.

• Humidity levels should not exceed 30 - 50%.
• Fix all leaky faucets and pipes, and eliminate collections of water around the outside of the house.
• Dehumidify basements, but empty and clean humidifier daily with a vinegar solution.
• Clean often any moldy surfaces in basement or in other areas of the home.

Exterminating Pests (Cockroaches and Mice).

• Use professional exterminators to eliminate cockroaches. (One study reported that ridding a home of cockroaches and cleaning the house using standard housecleaning techniques failed to eliminate the cockroach allergens themselves.)
• Exterminate mice and attempt to remove all dust, which might contain mouse urine and dander.
• Keep food and garbage in closed containers.
• Keep food out of bedrooms.

Outdoor Protection

Avoiding Outdoor Allergens. The following are some recommendations for avoiding allergens outside:

• Start taking allergy medications 1 - 2 weeks before ragweed season begins. Be sure to take allergy medications before going outside. If regular medications do not work, ask your doctor about allergy shots.
• Camping and hiking trips should not be scheduled during times of high pollen count (May and June for grass pollen and September to October for ragweed).
• Patients who are allergic should avoid barns, hay, raking leaves, and mowing grass. (A mask can be worn during outdoor chores to help reduce pollen exposure.)
• Sunglasses can help prevent pollen from getting into eyes.
• After being outdoors, clean off pollen residue by bathing, washing hair and clothes, and using a nasal salt water rinse.
• Keep doors and windows closed during pollen season.

Dietary Factors

Some evidence suggests that people with allergic rhinitis and asthma may benefit from a diet rich in omega-3 fatty acids (found in fish, almonds, walnuts, pumpkin, and flax seeds) and fruits and vegetables (at least five servings a day). Investigators are also studying probiotics -- so-called good bacteria, such as lactobacillus and bifidobacterium, which can be obtained in supplements. Some studies have found that probiotics may help reduce allergic rhinitis symptom severity and medication use.