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Managing Allergies

How to Control Your Seasonal Allergies

Man sneezing

Fast Facts

  • Allergies are reactions of your immune system to one or more things in the environment.
  • The immune system is your body's defense system. In allergic reactions, however, it is responding to a false alarm.
  • Pollens and mold spores can cause seasonal allergies.
  • Allergies from pollens and molds can cause runny and blocked noses, sneezing, nose and eye itching, runny and red eyes rashes, or asthma. Allergies typically make you feel bad.

—Source: National Institute of Allergy and Infectious Diseases

Allergic reactions occur when the body wrongly defends itself against something that is not dangerous. A healthy immune system defends against invading bacteria and viruses. During allergic reactions, however, the immune system fights harmless materials, such as pollen or mold, with production of a special class of antibody called immunoglobulin E (IgE).

Treat respiratory allergy with antihistamines, topical nasal steroids, cromolyn sodium, decongestants, or immunotherapy. (See page 24 for details.)

Plant Pollen

Ragweed and other weeds, such as curly dock, lambs quarters, pigweed, plantain, sheep sorrel, and sagebrush are prolific producers of pollen allergens. Ragweed season runs from August to November, but pollen levels usually peak by mid-September in many areas in the country. Pollen counts are highest in the morning, and on dry, hot, windy days.

Protecting Yourself

  • Between 5:00 and 10:00 in the morning, stay indoors. Save outside activities for late afternoon or after a heavy rain, when pollen levels are lower.
  • Keep windows in your home and car closed to lower exposure to pollen. Keep cool with air conditioners. Don't use window or attic fans.
  • Use a dryer, not a line outside; dry your clothes and avoid collecting pollen on them.

Grass Pollen

Grass pollens are regional as well as seasonal. Their levels also are affected by temperature, time of day, and rain. Only a small percentage of North America's 1,200 grass species cause allergies, including:

  • Bermuda grass
  • Johnson grass
  • Kentucky bluegrass
  • Sweet vernal grass
  • Timothy grass
  • Orchard grass

Protecting Yourself

  • Between 5:00 and 10:00 a.m., stay indoors. Save outside activities for late afternoon or after a heavy rain, when pollen levels are lower.
  • Keep windows in your home and car closed to lower exposure to pollen. Keep cool with air conditioners. Don't use window or attic fans.
  • Use a clothes dryer, not a line outside, to avoid collecting pollen on them.
  • Have someone else mow your lawn. If you mow, wear a mask.

Tree Pollen

Trees produce pollen earliest, as soon as January in the south, and as late as May and June in the northeast. They release huge amounts that can be distributed miles away. Fewer than 100 kinds of trees cause allergies. The most common tree allergy is against oak, but others include catalpa, elm, hickory, sycamore, and walnut.

Protecting Yourself

  • Follow the same protective strategies related to time of day, closed windows, and clothes dryers noted in "Protecting yourself" under Grass Pollen, above.
  • Plant species that do not aggravate allergies, such as crape myrtle, dogwood, fig, fir, palm, pear, plum, redbud, and redwood trees, or the female cultivars of ash, box elder, cottonwood, maple, palm, poplar, or willow trees.

Seasonal Allergies: Nuisance or Real Health Threat?

For most people, hay fever is a seasonal problem—something to endure for a few weeks once or twice a year. But for others, such allergies can lead to more serious complications, including sinusitis and asthma.

  • Sinusitis is one of the most commonly reported chronic diseases and costs almost $6 billion a year to manage. It is caused by inflammation or infection of the four pairs of cavities behind the nose. Congestion in them can lead to pressure and pain over the eyes, around the nose, or in the cheeks just above the teeth. Chronic sinusitis is associated with persistent inflammation and is often difficult to treat. Extended bouts of hay fever can increase the likelihood of chronic sinusitis. But only half of all people with chronic sinusitis have allergies.
  • Asthma is a lung disease that narrows or blocks the airways. This causes wheezing, shortness of breath, coughing, and other breathing difficulties. Asthma attacks can be triggered by viral infections, cold air, exercise, anxiety, allergens, and other factors. Almost 80 percent of people with asthma have allergies, but we do not know to what extent the allergies trigger the breathing problems. However, some people are diagnosed with allergic asthma because the problem is set off primarily by an immune response to one or more specific allergens. Most of the time, the culprit allergens are those found indoors, such as pets, house dust mites, cockroaches, and mold. Increased pollen and mold levels have also been associated with worsening asthma.
Read More "Managing Allergies" Articles

How to Control Your Seasonal Allergies / Allergy Diagnosis and Treatment / Seasonal Allergy Research at NIH

Spring 2013 Issue: Volume 8 Number 1 Page 22-23