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Seasonal Allergies

Controlling Seasonal Allergies

ragweed plant with pollen

In spring and summer, seasonal allergies affect millions of Americans. During allergic reactions, a person's immune system fights allergens, such as pollen or mold, that a normal immune system would not. Air purifiers, filters, humidifiers, and conditioners provide varying degrees of relief, but none is 100 percent effective. Various over-the-counter or prescription medications offer relief, too:

  • Antihistamines. These medications counter the effects of histamine, the substance that makes eyes water and noses itch and causes sneezing during allergic reactions.
  • Nasal steroids.These anti-inflammatory sprays help decrease inflammation, swelling, and mucus production.
  • Cromolyn sodium. A nasal spray, cromolyn sodium can help stop hay fever, perhaps by blocking release of histamine and other symptom-producing chemicals.
  • Decongestants. Available in capsule and spray form, decongestants thin nasal secretions and can reduce swelling and sinus discomfort. Intended for short-term use, they are usually used in combination with antihistamines.
  • Immunotherapy. Immunotherapy (allergy shots) might provide relief for patients who don't find relief with antihistamines or nasal steroids. They alter the body's immune response to allergens, helping to prevent allergic reactions.

Seasonal Allergy Research at NIH

  • Allergen and T-Cell Reagent Resources for the Study of Allergic Diseases: This National Institute of Allergy and Infectious Diseases (NIAID) program is to identify the portion of a molecule to which an antibody binds, and to develop immune-based therapeutics.
  • Asthma and Allergic Diseases Cooperative Research Centers: In 1971, NIAID established its Asthma and Allergic Diseases Centers to conduct basic and clinical research on the mechanisms, diagnosis, treatment, and prevention of asthma and allergic diseases.
  • Immune Tolerance Network (ITN): The ITN is an international consortium of investigators in the United States, Canada, Europe, and Australia dedicated to the development and evaluation of novel, tolerance-inducing therapies in such disorders as asthma and allergies.
  • Inner-City Asthma Consortium: Since 1991, the NIAID has funded research on asthma in inner-city areas with the goal of improving the treatment of children living in environments where the prevalence and severity of asthma is particularly high.

Fast Facts

  • Allergies are reactions of your immune system to one or more things.
  • Pollens and mold spores can cause seasonal allergic reactions.
  • The immune system is your body's defense system. In most allergic reactions, however, it is responding to a false alarm.
  • Allergies cause runny noses, sneezing, itching, rashes, swelling, hives, abdominal pain, or asthma. Allergies typically make you feel bad. However, a severe reaction, called anaphylaxis, is life threatening.
Source: National Institute of Allergy and Infectious Diseases (NIAID) and National Institute of Environmental Health Sciences (NIEHS)

To Find Out More

Spring 2012 Issue: Volume 7 Number 1 Page 26