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Asthma Health Center

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Allergies and Asthma

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Asthma attacks (worsening of asthma symptoms) can be triggered by allergies, which can temporarily increase the inflammation of the airways in a susceptible person.

What Is an Allergy?

An allergy is the immune system's reaction when exposed to what is otherwise a harmless substance, such as plant pollen, mold, or animal hair, skin or saliva. The immune system acts as a body defense, yet for people with allergies, the immune system treats these substances, called "allergens," as if they are harmful, causing a disruption to normal body functions. Allergens are what trigger a series of reactions by the immune system during an allergic reaction.

What Allergies Cause Asthma?

Inhaled Allergens. The most important allergens for people with allergic asthma appear to be those asthma triggers that are inhaled. Hay fever or seasonal allergic rhinitis occurs when a person comes in contact with an allergen or a substance that he or she is sensitive to. Common inhaled allergens include:

Medical experts recommend that all people with allergies and asthma try to identify possible inhaled allergens that may trigger asthma symptoms.

Food Allergies.Food allergies rarely cause asthma yet they can cause a severe life-threatening reaction. The most common foods associated with allergic symptoms are:

  • Eggs
  • Cow's milk
  • Peanuts
  • Tree nuts (such as almonds, pecans, walnuts)
  • Soy
  • Wheat
  • Fish
  • Shrimp and other shellfish

Food preservatives can also trigger asthma. Additives, such as sodium bisulfite, potassium bisulfite, sodium metabisulfite, potassium metabisulfite, and sodium sulfite, are commonly used in food processing or preparation and may be found in foods such as:

  • Dried fruits or vegetables
  • Potatoes (packaged and some prepared)
  • Wine and beer
  • Bottled lime or lemon juice
  • Shrimp (fresh, frozen, or prepared)
  • Pickled foods

Symptoms of food allergy can include hives, rash, nausea, headache, vomiting, diarrhea, sneezing, and nasal congestion. Some people may experience wheezing or anaphylaxis -- a swelling of the throat that can cut off the airway.

If you suspect that certain foods may be the cause of your asthma, discuss this with your doctor. Allergy skin testing can be done to determine if you are allergic to these foods.

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