Exercise-induced anaphylaxis is a rare form of anaphylaxis that happens during or after exercising and can be frightening and dangerous. It can come on suddenly in those who have never experienced it before, and sometimes is brought on by certain foods eaten before exercising. Since it is usually caused by over-exertion, there are specific ways you can prevent it from happening, or lessen the chances that it will occur.
Anaphylaxis
Anaphylaxis is a dangerous allergic reaction that comes on rapidly and can cause death. It requires immediate medical attention and follow-up care by an allergist. According to the American Academy of Allergy Asthma and Immunology website, anaphylaxis is triggered when your immune system overreacts to a normally harmless substance. Symptoms appear within minutes to a few hours after exposure to the allergen. Common causes are foods, stinging insects, medications, latex and, in rare cases, exercise.
Symptoms
With exercise-induced anaphylaxis you may experience the following symptoms: shortness of breath, stomach cramping, headache, dizziness, swelling of the face, tongue and hands, itching and hives. These symptoms appear anywhere from 5 to 30 minutes after beginning to exercise. They can lead to life-threatening situations, such as obstruction of the airways or shock. More often than not, exercise analphylaxis occurs during aerobic exercise. Sometimes exercise-induced anaphylaxis is caused by specific foods. Shellfish, nuts, celery, seeds, bananas, kiwi, wheat and dairy products are known offenders. Sometimes it occurs after ingesting an aspirin or non-steroidal ani-inflammatory.
Prevention
The results of a 10-year follow-up study of exercise-induced anaphylaxis were published in the "Journal of Allergy Clinical Immunology." There were 279 questionnaire respondents who met the criteria for EIA and had an average of 10.6 years of symptoms, mostly triggered by jogging or brisk walking. In the follow-up, the subjects reported a decrease in the frequency of attacks or being free of them altogether. They reduced their attacks by avoiding exercise during extremely cold or hot weather, avoiding ingesting certain foods before exercising, restricting exercise during allergy season or humid weather and managing their symptoms with antihistamines and epinephrine.
Mast Cells
Mast cells are white blood cells that release histamine into the blood stream, causing small blood vessels to increase in diameter. This condition can lead to very low blood pressure and eventually cause shock. Some experts believe that mast cells are responsible for the pathophysiology of exercise-induced anaphylaxis. Since mast cells are also found in the mucus membrane of the pharynx, you could also experience a blocked airway. A medication called ketotifen stabilizes mast cells, preventing the release of histamine.
