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Does More Pollen Mean Worse Allergy Symptoms? Probably

Does More Pollen Mean Worse Allergy Symptoms? Probably

New studies show an increase in pollen due to climate change

ARLINGTON HEIGHTS, Ill. (April 21, 2021) – Your nose may already be aware of the findings from a recent study, namely that climate change has made pollen season longer and worse throughout North America. It’s definitely not good news for those who suffer with nasal allergies.

“May is Asthma and Allergy Awareness Month,” says allergist Luz Fonacier, MD, president of the American College of Allergy Asthma and Immunology. “It’s a perfect time to examine why you may be suffering more with your allergies, and what you might be able to do about it.”

The study that’s been in the news examined pollen counts from 60 North American stations between 1990 and 2018. The researchers found that the pollen seasons for plants like trees, grasses, and weeds showed a 20-day increase in length and a 21% increase in pollen concentration across North America during the 28-year time frame.

You may be wondering how climate change and increased temperatures make your nasal allergy symptoms worse. Three things happen related to global warming that can make your allergies miserable:

  1. First, the growing season of plants is longer and starts earlier than in the past, so the length of time pollen is in the air to cause symptoms has increased.
  2. Not only is the season longer, but the amount of pollen produced by each plant is greater. According to the American College of Allergy, Asthma and Immunology, one ragweed plant can produce as much as 1 billion pollen grains.
  3. Lastly, and very importantly, the pollen which is produced is more allergenic. That means it is more likely to trigger an allergic reaction with fewer grains of pollen in the air than pollen which is not as allergenic. In other words, the potency of the pollen is affected. It’s this triple play that is leading to more severe nasal allergies, which impair your quality of life.

What’s the best way to deal with a worsening pollen season? “Get ahead of it,” says Dr. Fonacier. “If you know it’s likely that your allergy symptoms will arrive earlier in the spring or fall season, start taking your medications sooner. If you begin your medications 2-3 weeks before your symptoms begin in earnest, chances are your suffering will be lessened.”

Pollens from trees are higher in the spring, grasses in the summer and weeds in the fall. This may vary depending on weather conditions and where you live. If possible:

  • Keep windows closed during pollen season, especially during the day. Use your air conditioning whenever possible.
  • To avoid pollen, know which pollens you are sensitive to and then check pollen counts. In spring and summer, during tree and grass pollen season, levels are highest in the evening. In late summer and early fall, during ragweed pollen season, levels are highest in the morning.
  • Take a shower, wash your hair, and change clothing after working or playing outdoors.
  • Wear sunglasses and a hat outside to keep pollen out of eyes and hair. Your COVID-19 mask could provide a protective barrier against pollen.

If you think your fall and spring allergies are getting worse each year, you are probably right. If staying indoors during these times of year and OTC allergy medications are not doing the trick to control your symptoms, find a board-certified allergist to help get relief. Use the ACAAI Find an Allergist tool to locate an allergist in your area.


The ACAAI is a professional medical organization of more than 6,000 allergists-immunologists and allied health professionals, headquartered in Arlington Heights, Ill. The College fosters a culture of collaboration and congeniality in which its members work together and with others toward the common goals of patient care, education, advocacy and research. ACAAI allergists are board-certified physicians trained to diagnose allergies and asthma, administer immunotherapy, and provide patients with the best treatment outcomes. For more information and to find relief, visit Join us on FacebookPinterest and Twitter.

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