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Coping with airborne allergens

Pollen, mold, dust and pet dander may all cause allergy symptoms. But you can reduce your exposure to each of these airborne allergens.

There's nothing like a breath of fresh air.

But what may look like pure, clear air may in fact be laced with billions of microscopic particles called airborne allergens.

When inhaled, these allergens can cause symptoms such as sneezing; congestion; runny nose; and itchiness in the nose, roof of the mouth, throat, eyes and ears.

While it's impossible to completely rid the air of allergens, there are ways to help reduce your exposure. Here are the basics about some common airborne allergens, along with some steps you can take.


Pollens are tiny grains that plants make to aid in fertilization. Pollens from plants that attract insects, such as roses, are too heavy to be blown on the wind and usually don't trigger allergies. But certain trees, grasses and weeds yield small, light, dry pollens that can be whisked about by wind currents. These are the pollens that cause symptoms in people who are allergic to them.

The pollinating season usually lasts from February or March through October. Trees tend to pollinate first, followed by grasses and then weeds.

To reduce your exposure:

  • Try to stay indoors when the pollen count is reported to be high, and also on windy days. You can check the pollen count in your area at the National Allergy Bureau's website.
  • Minimize activity outdoors during the morning, when most pollen is emitted.
  • Keep car and house windows closed.
  • Don't mow lawns. And avoid freshly cut grass; mowing stirs up pollens.
  • Don't hang sheets or clothing out to dry; pollens may collect in them.
  • If you must work outdoors, wear a face mask designed to filter pollen out of the air.

Mold spores

Molds are microscopic fungi that grow in damp materials. Their small spores can float in the air and may cause symptoms when inhaled.

Outside, molds can be found in soil, vegetation and rotting wood—especially in moist, shady areas. The spores typically start to appear after a spring thaw and reach their peak when the weather gets warm and dry.

Indoors, molds can be found in attics, basements, bathrooms, refrigerators and other food storage areas, garbage containers, carpet and upholstery.

In the south and on the west coast, outdoor molds can be found all year long. In damp indoor areas, molds can hang around all year as well.

According to the American Academy of Allergy, Asthma & Immunology, the Environmental Protection Agency and other experts, the key to controlling mold indoors is to control moisture:

  • Fix leaky plumbing.
  • Empty air conditioner, refrigerator and dehumidifier drip pans regularly.
  • Use exhaust fans or open the windows in kitchens and bathrooms when showering, cooking or running the dishwasher.
  • After bathing, wipe down damp surfaces and dry completely.
  • Make sure the clothes dryer is vented to the outside.
  • Don't keep a lot of indoor plants. And don't water them too much. Wet soil encourages mold growth.
  • Maintain indoor humidity below 60%, ideally between 30% and 50%. Humidity levels can be measured by devices called hygrometers, available at hardware stores. Dehumidifiers can reduce the amount of moisture in the air, but be sure to empty and clean the container often to keep mildew at bay.
  • Avoid raking leaves in the fall. It stirs up mold spores.


All pets with fur or feathers can cause allergies, including dogs, cats, birds, hamsters and guinea pigs, according to the American Lung Association (ALA).

Symptoms are triggered by pet dander (tiny scales or particles that fall off hair, feathers or skin) or saliva.

To reduce your exposure:

  • Think about finding another home for pets that cause allergic reactions.
  • Keep pets out of bedrooms.
  • Clean and brush pets outdoors. Weekly pet baths may help reduce the amount of pet saliva and dander in the home. Ideally a nonallergic person should do these tasks.
  • Keep pets away from fabric-covered furniture, carpets and stuffed toys.
  • Avoid visiting households with pets. If this is not possible, take allergy medication just before your visit.

Dust mites

These microscopic pests are found in house dust, carpets, bedding and upholstered furniture. Several thousand mites can be found in just a pinch of dust, according to the ALA. Their waste products can trigger allergic reactions.

To help keep dust mites at bay:

  • Dust often with a damp cloth or mop.
  • Cover mattresses, box springs and pillows with allergen-proof fabric covers. Put tape over the zipper.
  • Avoid down-filled comforters and pillows.
  • Wash bedding weekly in hot water.
  • If possible, replace carpets with washable throw rugs. Wash the rugs often in hot water. This is especially important in bedrooms.
  • Avoid upholstered furniture, which can trap allergens. Replace dust-collecting blinds and long drapes with window shades or washable curtains.
  • Vacuum any carpeted or fabric-covered areas at least once a week. Consider wearing a mask while vacuuming, having someone else vacuum for you, or using a vacuum with a high-efficiency (HEPA) filter that helps keep dust and allergens from being stirred up.

One last note

If you can't avoid allergens, medicine may help.

Pharmacies stock a wide array of over-the-counter medicines to help curb allergy symptoms. However, if these drugs don't provide relief or if they cause unwanted side effects, such as sleepiness, talk with your doctor. Prescription medication or allergy shots may be the answer.

Reviewed 12/28/2022

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