Allergy

In this Article

• What does an allergy mean?
• What causes allergies?
• Who is at risk and why?
• What are common allergic conditions and their symptoms and signs?
• Hay Fever
• Asthma
• Allergic Eyes
• Allergic Eczema
• Hives
• Allergic Shock
• Where are allergens? Everywhere
• In the air we breathe
• In what we ingest
• Touching our skin
• Injected into our body
• Allergy At A Glance
• Pictures of Common Allergy Triggers - Slideshow
• Pictures of Pets and Allergies - Slideshow
• Pictures of Home Allegy - Slideshow
• Patient Discussions: Allergies - Describe Your Experience

Injected into Our Body

The most severe reactions can occur when allergens are injected into the body and gain direct access to the blood stream. This access carries the risk of a generalized reaction, such as anaphylaxis, which can be life-threatening. The following are commonly injected allergens that can cause severe allergic reactions:

• Insect venom
• Medications
• Vaccines (including allergy shots)
• Hormones (for example, insulin)

Allergy At A Glance

• Allergy involves an exaggerated response of the immune system.
• The immune system is the body's organized defense mechanism against foreign invaders, particularly infections.
• Allergens are substances that are foreign to the body and can cause an allergic reaction.
• IgE is the allergy antibody.
• Allergies can develop at any age.
• Your risk of developing allergies is related to your parents' allergy history.

REFERENCES: Fiocchi A, Assa'ad A, Bahna S; Adverse Reactions to Foods Committee; American College of Allergy, Asthma and Immunology. Food allergy and the introduction of solid foods to infants: a consensus document. Adverse Reactions to Foods Committee, American College of Allergy, Asthma and Immunology. Ann Allergy Asthma Immunol. 2006 Jul;97(1):10-20; quiz 21, 77.

Price D, Bond C, Bouchard J, Costa R, Keenan J, Levy ML, Orru M, Ryan D, Walker S, Watson M. International Primary Care Respiratory Group (IPCRG) Guidelines: management of allergic rhinitis. Prim Care Respir J. 2006 Feb;15(1):58-70. Epub 2005 Dec 27.

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.

Flinterman AE, Pasmans SG, Hoekstra MO, Meijer Y, van Hoffen E, Knol EF, Hefle SL, Bruijnzeel-Koomen CA, Knulst AC. Determination of no-observed-adverse-effect levels and eliciting doses in a representative group of peanut-sensitized children. J Allergy Clin Immunol. 2006 Feb;117(2):448-54.

Scibilia J, Pastorello EA, Zisa G, Ottolenghi A, Bindslev-Jensen C, Pravettoni V, Scovena E, Robino A, Ortolani C. Wheat allergy: a double-blind, placebo-controlled study in adults. J Allergy Clin Immunol. 2006 Feb;117(2):433-9.

Medically Reviewed By: Ellen Reich, MD, Board Certified in Allergy and Immunology, Board Certified in Pediatrics

Allergies - Describe Your Experience

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