Allergy, Asthma, and Immunology

Pollen

What is pollen?

Pollen is the cells of flowering plants, including trees, grasses, and weeds. Pollen is microscopic in size.

Pollen is the most common cause of seasonal allergic rhinitis, sometimes known as "hay fever."

Which plants produce pollen that cause allergic reactions?

Plants that have powdery granules of pollen that are easily blown by the wind, include the following:

• trees - oak, western red cedar, elm, birch, ash, hickory, poplar, sycamore, maple, cypress, walnut, and others.
  
  
• grasses - timothy, Bermuda, orchard, sweet vernal, red top, some blue grasses, and others.
  
  
• weeds - ragweed, sagebrush, pigweed, tumbleweed, Russian thistle, cockleweed, and others.

Most flowering plants, such as roses, have heavier, waxy pollens that do not trigger allergies.

When is "pollen season?"

Each plant has a pollen season. It usually starts in the spring, but may begin as early as January in the western areas of the US. The season usually lasts until October.

Can allergic rhinitis in pollen season be prevented?

To lessen the effects of allergic rhinitis during pollen season, the American Academy of Allergy, Asthma, and Immunology suggests the following:

• Keep windows closed at night and use air conditioning - which cleans, cools, and dries the air.
  
  
• Minimize outdoor activities early in the morning, between 5:00 and 10:00 a.m., when pollen is most prevalent.
  
  
• Keep car windows closed when traveling.
  
  
• Take vacations in areas where pollen is not as prevalent - such as the ocean.
  
  
• Give your child his/her medications, as prescribed by his/her physician.
  
  
• Minimize your child's time spent outdoors when the pollen count is high.
  
  
• Do not rake leaves or have your child jump in piles of raked leaves during pollen season.
  
  
• Do not hang your child's bedding or clothing outside to dry.