Exercise-Induced Anaphylaxis

Definition

Exercise-induced anaphylaxis (EIA) is a rare condition characterized by a serious allergic reaction that occurs during or shortly after a person exercises. The reaction may be triggered by exercise alone or when a person eats or takes certain medications before exercising.

Description

Exercise-induced anaphylaxis (EIA) is a unique condition with characteristics that are identical to anaphylaxis. This is the severe allergic reaction to allergens such as food, insect stings, or medications such as antibiotics. However, EIA is a condition about which little was known as of September 2011.

Eating a specific food like shellfish or one containing wheat before exercising could cause exerciseinduced anaphylaxis. The reaction could also occur when eating any food or taking some medications before exercising. Weather conditions may also cause the reaction.

How someone reacts to these triggers is unpredictable. A person could eat a certain food one day, exercise, and not experience symptoms. The next time the person eats the same food and does the same exercise, the individual could experience EIA.

The symptoms generally improve when the person stops exercising.

Allergic reactions

An anaphylactic reaction is a severe and possibly life-threatening reaction to an allergen. The milder reaction to an allergen such as pollen or dust causes symptoms similar to those experienced with a cold. The person sneezes or experiences a runny, itchy, or stuffed-up nose. The eyes water and itch, and the person may feel fatigued.

The anaphylactic reaction produces a range of symptoms that affect various parts of the body including the respiratory, cardiovascular, and gastrointestinal systems. Severe symptoms of anaphylaxis include difficulty breathing, a choking sensation, and nausea. Anaphylaxis occurs suddenly and is immediately severe within minutes. As breathing becomes more difficult, the person's blood pressure drops and the person goes into anaphylactic shock. If untreated, the person could lose consciousness or die.

Demographics

Exercise-induced anaphylaxis in adults is triggered by food in about one-third of patients, according to the “Guidelines for the Diagnosis and Management of Food Allergy in the United States,” published in December 2010 by the National Institutes of Health of the U.S. Department of Health and Human Services.

However, EIA is a rare condition. Some research indicated that more women than men experienced EIA. That research included a 1993 survey of 279 people who met the criteria for EIA. It drew responses from 199 women and 80 men, according to “The Natural History of Exercise-Induced Anaphylaxis: Survey Results from a 10-Year Follow-Up Study,” an article published in the July 1999 issue of the Journal of Allergy and Clinical Immunology. Authors including Nancy A. Shadick, MD, MPH, described a survey group that ranged in age from 13 to 77 years old. The average age was 37.5 years old, and respondents experienced EIA symptoms for an average of 10.6 years.

Among the survey findings were that 78% of subjects experienced symptoms when jogging and 42% experienced them when walking briskly. During the previous year, the frequency of attacks lessened for 47% of respondents. The condition stabilized for 46% of people, and 100 subjects (41%) experienced no attacks.

That survey and other studies were cited in the article “Exercise-Induced Anaphylaxis” by authors including Peter N. Huynh, MD, and Harumi Jyonouchi, MD. The online Medscape Reference article that was updated on March 29, 2011, also listed that:

Medical experts expected that the amount of people with this condition would increase. That projection was based on the growing number of people diagnosed with allergies.

Causes and symptoms

The person diagnosed with a severe allergy to an allergen like peanuts, eggs, or antibiotics knows to avoid the allergens, but the individual diagnosed with exercise-induced anaphylaxis faces uncertainty about whether there will be an allergic reaction, what will cause the reaction, and the severity of the symptoms.

Allergic reactions

What is known is that heredity usually plays a role in how the body responds to allergens such as food. An allergic reaction is related to the production of immunoglobulin E (IgE), an antibody found in the blood. Antibodies are part of the immune system and protect the body against invasive elements like viruses.

The allergic reaction occurs when food is digested. This causes cells to produce large amounts of IgE, according to the Mayo Clinic. When IgE is released, it attaches to mast cells. These cells are found in body tissues, particularly in the nose, throat, lungs, skin, and gastrointestinal tract.

When the individual with a food allergy eats that food again, the IgE on the mast cells responds. The cells release chemicals including histamine, a chemical produced during an allergic reaction. Early symptoms include hives (urticaria), which are red welts on the surface of the skin. They may be filled with fluid and are frequently itchy.

Exercise-induced anaphylaxis

The three types of exercise-induced anaphylaxis are exercise only, food-dependent triggered by a specific food like shellfish, and food-dependent triggered by a nonspecific food. Exercise is involved in all forms of this condition.

EXERCISE. EIA is a rare condition, and the allergic reactions vary even when the same exercise is performed. While jogging is frequently cited as a cause for exercise-induced anaphylaxis, many types of exercise could bring on EIA. People may experience the reaction while doing or finishing activities such as running, dancing, bicycling, or playing an active sport like tennis or soccer. Furthermore, walking briskly or doing yard work like raking leaves could trigger the allergic reaction. Other cases of this reaction involved shoveling snow and riding horses.

FOOD-DEPENDENT EXERCISE-INDUCED ANAPHYLAXIS. Just eating an allergy-provoking food does not cause an allergic reaction for a person diagnosed with food-dependent EIA. The allergic reaction occurs when the individual exercises from two to five hours after eating.

Certain foods, particularly those containing wheat, cause the exercise-induced anaphylactic reaction. Other foods commonly associated with the allergic reaction are shellfish, peanuts, tomatoes, and corn. In addition, the allergic reaction has been triggered by consuming milk, lettuce, celery, fruits, some meats, beans, soybeans, peas, and rice.

OTHER ALLERGY TRIGGERS. Aspirin and remedies that include nonsteroidal anti-inflammatory drugs such as ibuprofen may also trigger reactions when taken four or five hours before exercising.

KEY TERMS
Allergen—
A foreign substance that causes an allergic reaction in some sensitive people but not in most others.
Bronchi—
Tubular airway branch structures within the lungs.

Weather may also relate to exercise-induced anaphylaxis. People have experienced the allergic reaction when exercising during allergy season, and when the weather was extremely hot, humid, or cold.

Symptoms of exercise-induced anaphylaxis

An exercise-induced reaction occurs during exercise or shortly after a person finishes exercising. When the person stops exercising, symptoms usually improve. If the person continues exercising, the symptoms worsen within minutes.

Symptoms of exercise-induced anaphylaxis may start with itching on the face or eyes. Within minutes, hives may appear, along with other serious symptoms that could include wheezing, abdominal cramping, nausea, vomiting, diarrhea, a headache, light-headedness, dizziness, and shortness of breath. The person may also experience angioedema, which is a swelling below the surface of the skin.

As the reaction worsens, the blood pressure drops. In severe cases, a person will go into anaphylactic shock. If the condition isn't treated immediately, it could be fatal.

Diagnosis

Anaphylaxis is a life-threatening condition, so the diagnosis may come after treatment in the emergency room for a severe allergic reaction. The person is then referred to an allergist, a physician also known as an immunologist. The allergist is trained to diagnose, treat, and manage allergies. The doctor will take a detailed patient history. The allergist also asks the patient to describe the allergic reaction. Other questions include what types of foods were consumed and how much time passed before the person experienced anaphylaxis.

The allergist will also educate the patient about how to manage the condition and prevent future anaphylactic reactions.

Treatment

Treatment starts with patient education so that a person learns to manage the condition and prevents the allergic reaction. Education includes information about exercise-induced anaphylaxis and instruction in how to use emergency-injectable epinephrine. This is a prescription medication delivered through devices such as the EpiPen, Adrerenaclick, and Twininject. The device contains a single dose of epinephrine that is injected into the thigh. The dosage provides temporary emergency relief, and the person must go immediately to the emergency room.

People diagnosed with EIA should always carry the injector because the food and activity triggers to this condition are so variable. In addition, exercise alone could cause a reaction.

Managing exercise-induced anaphylaxis

The person diagnosed with exercise-induced anaphylaxis can continue to exercise. However, it is important to create a plan to manage the condition before exercising. An individual with EIA should wear a medical alert bracelet or other jewelry with information about the condition. Patients should inform their family and other significant people about the diagnosis and the methods that will be used to manage EIA.

Planning to exercise

The allergist will advise the patient about whether it is necessary to adjust the intensity or duration of an exercise. The physician will also tell the patient how long to wait to exercise after eating. Some doctors say that waiting five hours is sufficient. The article by Huynh and others stated that when the trigger is known, the person should avoid eating that food for 12 hours before exercising. If the food that triggers the reaction is not known, people should not eat anything from six to eight hours before exercising, according to the article. One way to prevent a reaction is to exercise before breakfast.

Prognosis

Since the triggers for EIA are so variable, the prognosis is based on actions the person takes to prevent reactions rather than treatment of the condition.

QUESTIONS TO ASK YOUR DOCTOR

By taking preventive measures, an individual does not need to give up exercising. When the 279 people in the 1993 survey were asked about allergic reactions during the previous year, many reported that they experienced no attacks, the attacks decreased, or the condition stabilized.

The improvement was credited to avoiding exercise in extremely hot or cold weather by 44% of subjects, avoiding eating certain foods before exercising by 37% of people, restricting exercise during allergy season by 36% of respondents, and restricting exercise during humid weather by 33%.

Prevention

The person diagnosed with exercise-induced anaphylaxis can generally continue to exercise. However, it is important to manage the condition by following the plan developed during treatment. The person should wear medical alert identification and always carry emergency-injectable epinephrine.

Some people diagnosed with EIA decide to stop exercising alone, and are accompanied by someone familiar with their condition and the use of emergency-injectable epinephrine.

Resources

WEBSITES

“Anaphylaxis.” American Academy of Allergy, Asthma and Immunology. http://www.aaaai.org/conditions-and-treatments/library/at-a-glance/anaphylaxis (accessed January 17, 2017).

“Guidelines for the Diagnosis and Management of Food Allergy in the United States: Summary of the NIAIDSponsored Expert Panel Report.” National Institute of Allergy and Infectious Diseases. NIAID.gov . (December 2010). https://www.niaid.nih.gov/diseases-conditions/food-allergy-guidelines-patients (accessed January 18, 2017).

Huynh, Peter N. “Exercise-Induced Anaphylaxis.” Medscape Reference. http://emedicine.medscape.com/article/886641-overview (accessed January 18, 2017).

Roush, Courtney. “Allergic to Running.” Running Times Magazine (January 1, 2006). http://www.runnersworld.com/injury-treatment/allergic-to-running (accessed January 18, 2017).

ORGANIZATIONS

Asthma and Allergy Foundation of America, 8201 Corporate Dr., Ste. 1000, Landover, MD, 20785, 1-800-7278462, http://www.aafa.org/ .

Liz Swain

  This information is not a tool for self-diagnosis or a substitute for professional care.