Sports Medicine: Just the Facts

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CHAPTER 37 • ALLERGIC DISEASES IN ATHLETES 227

should be suspected in any athlete with a reaction that
occurs outdoors, even if the patient does not recall
being stung.
•Exercise-induced anaphylaxis is a rare condition asso-
ciated with exercising within 2–4 h after food inges-
tion. It is characterized by the usual manifestations of
anaphylaxis beginning within 5 to 30 min of exercise
and lasting up to 3 h. The medical history should
explore the relationship of symptom onset to physical
exercise to assess for this rare trigger.



  • The physical manifestations of anaphylaxis involve
    multiple sites including the skin, upper airway,
    lower airway, and cardiovascular system. The phys-
    ical examination should start by evaluating upper
    airway patency by listening for inspiratory stridor
    and looking for oral or pharyngeal edema. The res-
    piratory status can be assessed by observing work of
    breathing and accessory muscle use. Auscultation
    may reveal wheezing indicating acute bron-
    chospasm. A set of vital signs is critical to patient
    management, looking for any evidence of cardio-
    vascular or respiratory compromise. Once the ABCs
    are assessed and secured, the skin can be examined
    for the presence of generalized erythema, urticaria,
    and angioedema.


ACUTE MANAGEMENT



  • Initial management of anaphylaxis should always
    start with epinephrine 0.2–0.5 cc intramuscular
    (IM) or subcutaneous(SQ) of 1:1000, even if symp-
    toms are mild. The IM route is preferred, especially
    in children, as SQ injection may delay absorption.
    Doses may be repeated every 10–15 min if symp-
    toms persist. Intravenous (IV) epinephrine at
    1 mcg/min of 1:10,000 (10 mcg/mL) can be consid-
    ered for symptoms resistant to repeated SQ or IM
    administration. The IV dosage can be increased to
    2–10 mcg/min for severe reactions. Patients on beta-
    blockers may not respond to epinephrine. In these
    cases Glucagon 2–5 mg IM/SQ is beneficial.
    Supportive therapy includes: oxygen for hypox-
    emia, recumbent positioning and IV fluids for
    hypotension, and inhaled beta-agonists or racemic
    epinephrine for bronchospasm. Antihistamines
    (diphenhydramine 1–2 mg/kg or 25–50 mg IV/po)
    may provide additional benefit. Corticosteroids,
    (prednisone 0.5–2.0 mg/kg up 125 mg) should also
    be considered to prevent late phase reactions.
    Neither antihistamines nor steroids should be used
    as substitutes for epinephrine. Their onset of action


is much slower and they are insufficient to prevent
or treat more severe anaphylaxis with respiratory or
cardiovascular involvement.


  • Mild anaphylaxis cases should be observed a mini-
    mum of 3 h after symptoms have resolved. Severe
    reactions should be observed at least 6 h and hospital-
    ization should be strongly considered to monitor for
    late phase reactions.


LONG-TERM MANAGEMENT


  • All patients with anaphylaxis need an action plan to
    include allergen identification, symptom recognition,
    and appropriate treatment. A provider knowledgeable
    in allergic disease should provide education on aller-
    gen avoidance, hidden allergens, and cross-reacting
    substances. All individuals should have an epineph-
    rine autoinjector with them at all times and be edu-
    cated on the indications and proper technique for its
    use. The trainer and coach should be familiar with
    anaphylaxis recognition and epinephrine use as well.
    The athlete should wear a medical alert bracelet at all
    times, indicating their condition and allergy if
    known.

  • Because there are no measures proven to prevent
    exercise-induced anaphylaxis, affected athletes
    should never exercise alone. Pretreatment with anti-
    histamines is not effective. The primary preventative
    strategy is to avoid eating for 4 h prior to exercise.
    Other measures that may limit attacks are to avoid
    NSAIDs and aspirin prior to exercise and to avoid
    outdoor exercise during periods of high humidity,
    temperature extremes, and the individual’s allergy
    season (Shadick, 1999). Occasionally skin testing
    can identify a specific food that the patient can
    avoid, but often the results are inconclusive. Athletes
    should carry an epinephrine autoinjector on their
    person when they don’t have immediate access to
    their gear bag. They should discontinue exercise at
    the first sign of symptoms and self-administer epi-
    nephrine.

  • Indications for allergy referral include: when further
    testing is necessary for an unclear diagnosis or an
    unknown inciting agent, when reactions are recurrent
    and difficult to control, or when desensitization is
    required such as for stinging insects or antibiotic
    administration. Allergists also serve as an impor-
    tant resource for athletes, parents, and coaches
    needing education on allergen avoidance as well as
    institution or reinforcement of an individual’s
    action plan.

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