Table of Contents
- Allergy facts
- Allergy overview
- What is an allergy?
- What is an allergy? (Continued)
- What causes allergies?
- What causes allergies? (Continued)
- Who is at risk for allergies and why?
- What are common allergic conditions, and what are allergy symptoms and signs?
- Allergic rhinitis (hay fever)
- Allergic eyes (conjunctivitis)
- Eczema (atopic dermatitis)
- Hives (urticaria)
- Where are allergens?
- In the Air We Breathe
- In What We Ingest
- Touching Our Skin
- Injected Into Our Body
Quick GuideAllergy: What Happens in a Nasal Allergy Attack
Anaphylactic shock is a potentially life-threatening allergic reaction that can affect a number of organs at the same time. Allergens that typically lead to anaphylaxis are foods, medications, and venom (bee stings). Aeroallergens rarely lead to anaphylaxis. Some or all of the following symptoms may occur:
- Hives, present in 80%-90% of cases
- Nasal congestion, runny nose, itchy eyes
- Swelling of the tongue and/or throat
- Abdominal discomfort, nausea, vomiting, diarrhea
- Shortness of breath, wheezing, coughing
- Low blood pressure, leading to lightheadedness, passing out, or shock
Anaphylactic shock is an emergent, life-threatening condition that occurs when blood vessels dilate excessively due to an allergic reaction, which causes a significant drop in blood pressure. This can result in inadequate blood flow to the organs in the body. Continue Reading
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American College of Allergy, Asthma, & Immunology. Food allergy: a practice parameter. Ann Allergy Asthma Immunol. 2006 Mar;96(3 Suppl 2):S1-68. No abstract available.
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Medically Reviewed By: Ellen Reich, MD, Board Certified in Allergy and Immunology, Board Certified in Pediatrics and Michael Manning, MD, of the American Board of Allergy and Immunology.
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