Anaphylaxis is caused by a severe allergic reaction that occurs after an exposure to a substance that a person's immune system has been sensitized to previously. The allergen causes the sensitized immune system to release histamine and other chemicals from different tissues in the body, which then causes the symptoms that occur. Common allergens include medications such as penicillin, peanuts, tree nuts, wheat, fish, shellfish, milk, eggs, and insect stings from bees, yellow jackets, wasps, hornets, and fire ants.
Anaphylaxis can be triggered by allergens in insect stings, food, certain medications or other substances.
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Allergies
About one out of five Americans suffers from allergies. An allergy is an exaggerated response from the immune system to a substance such as dust, pollen, pet dander or mold. Other common triggers include foods such as peanuts and ...
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