Allergic Reactions

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Anyone can develop an allergy to any substance at any time. Allergic reactions range from a small rash to the most severe reaction, anaphylaxis. However, some people, especially asthmatics, children, and those with a history of anaphylaxis, have an increased susceptibility to allergic reactions.

A serious and potentially life-threatening reaction is more likely to occur in individuals:

  • Who have previously had an anaphylactic reaction,

  • Who have allergies, and

  • Who have asthma and food allergies.

Children, their immune systems immature, are most likely to develop allergies to food. Children may outgrow allergies to milk, soy products, and eggs as they mature. They may not, however, outgrow allergies to peanuts, tree nuts, and shellfish. This is why infants and young children should not be exposed to foods such as nuts and shellfish prior to immune system maturation.

Sensitivity to insect bites seems to lessen over time, particularly among children. However, R.E. Reisman, in an article printed in the Journal of Allergy and Clinical Immunology, showed that people who have showed a prior reaction to insect stings have a 30% to 60% greater likelihood of experiencing a similar or more severe reaction if stung again.

There is no predictor for allergic reactions in a specific individual. There appears to be no set pattern, but the severity of allergic reaction seems to depend upon:

  • The amount of allergen exposed to and

  • The individual’s degree of hypersensitivity (this varies according to patient health and may be exacerbated by exercise and ingestion of other foods or alcohol.

A general rule of thumb to follow is: the more rapidly the symptoms of an allergic reaction begin, the more likely the reaction will be severe.

Anaphylaxis

Anaphylaxis, or anaphylactic shock, is an allergic reaction that can become fatal with in minutes. Fatality is due to either airway constriction or a rapid decrease in blood pressure, or both. The allergic reaction can affect one or more of the bodies organ systems. The severity of the reaction determines how many organ systems are affected.

The body treats the allergen as a foreign substance and reacts against it. Specifically the immune system goes on the “attack.” The immune system activates proteins called IgE antibodies, located on mast cells, to combat the foreign substance. Once the IgE reacts with a foreign substance, mast cells release histamines and leukotrienes (referred to as mediators).

Release of mediators results in:

  • Contraction of the smooth muscle in the respiratory and digestive tracts, and

  • Vascular dilation which results in a decrease in blood volume.

Anaphylaxis usually has a trigger. Triggers can be: food, medication, insect venom, or latex. If there is no specific trigger for an anaphylactic reaction it is referred to as idiopathic anaphylaxis.

It is estimated that over 40 million Americans suffer from allergic reactions severe enough to classified as anaphylaxis, and the number is growing yearly. The growth has been attributed to greater exposure to items such as peanuts, latex, and insect bites (especially fire ants). Also, researchers are now uncovering a large number of poorly documented anaphylactic reactions from ingested medications.

At Risk

  • 1.3 - 3 million people are allergic to insect stings (up to 400 insect sting deaths per year),

  • 5.4 - 7 million people have food allergies (125 yearly deaths due to food allergies),

  • 2.7 - 16 million are allergic to latex (8% - 17% of healthcare workers are allergic to latex),

  • 27 million are allergic to penicillin (5,400 deaths per year), and

  • Asthmatics are at a much higher risk.

Symptoms of Anaphylaxis

Most Common:

  • Hives,

  • Swelling of the throat, lips, tongue, and eyes, and

  • Difficulty breathing or swallowing.

Other Common Symptoms Include:

  • A metallic taste.

  • Itching in the mouth,

  • Abdominal cramps,

  • Nausea or vomiting,

  • Increased heart rate,

  • Rapid decrease in blood pressure,

  • A sudden feeling of weakness,

  • Anxiety or overwhelming sense of doom,

  • Collapse, and

  • Loss of consciousness.

Treatment

The best treatment is early recognition and proper action. Individuals who have known anaphylaxis to particular triggers should carry with them an EpiPen®. EpiPens® are single injection syringes containing epinephrine. If an anaphylactic reaction has begun, the individual selfinjects with the EpiPen®. The epinephrine causes a cessation in the allergic reaction.

After using the EpiPen® the individual should be transported to the emergency room for follow-up treatment. As many as 25% of anaphylactic reactions will recur within the next few hours. This is referred to as a biphasic reaction. Since biphasic reactions are so common, an ER visit is recommended.

All Athletic Trainers should be aware of these types of reactions and have at their disposal EpiPens®.

Visit: www.allergic-reactions.com or www.allergy.mcg.edu for more information.

 

 

©2000 - 2009 David Edell

Information on this site is not a substitute for physician directed care.

Please consult your personal physician for more detailed information

concerning specific injuries or illnesses.

Last Update for AthleticAdvisor.com: 10/24/2009 12:09:35 AM