Exercise-induced anaphylaxis (EIA) is condition in which anaphylaxis (a severe allergic reaction) occurs either during or after exercise. This information has been developed to help those affected by EIA to further understand their condition.
Risk factors for exercise-induced anaphylaxis
While EIA may occur on its own without co-factors (such as food or medication) needed to trigger symptoms, the vast majority of those with anaphylaxis occurring during exercise are allergic to a food ingested in the previous four to six hours, so it is called Food Dependent Exercise Induced Anaphylaxis (FDEIA). Most of the below information will concentrate on FDEIA.
Food Dependent Exercise Induced Anaphylaxis (FDEIA)
FDEIA can be difficult to diagnose, especially if it is foods other than wheat or seafood. People with EIA or FDEIA are sometimes asked to keep a food diary to assist their clinical immunology/allergy specialist with identification of a related food trigger. The food does not normally result in an allergic reaction when eaten alone, but can trigger anaphylaxis when the food is eaten in the four to six hours before exercise or sometimes even four hours after exercise.
With FDEIA, the amount of activity that triggers a reaction may vary. Exercise is not necessarily exercise that requires more energy (E.g. running, bike riding, fitness class). Some people at risk can develop symptoms from day to day activities that require less energy such as walking, lifting boxes, doing house work (E.g. vacuuming or cleaning) or even rushing to a bus stop, a meeting or back to work from your lunch break.
Other factors such as a viral infection, lack of sleep or tiredness (or other factors mentioned below) may lead to less exercise being required to trigger symptoms.
Medication and EIA: Anaphylaxis may occur when a non-steroidal anti-inflammatory drug (NSAID), such as aspirin or ibuprofen, has been taken prior to exercise.
Food, NSAIDs and FDEIA: The combination of a trigger food and NSAIDs prior to exercise has the potential to trigger FDEIA. In some individuals, simply taking NSAIDs if you have consumed the trigger food can result in an allergic reaction.
Co-factors that can worsen an allergic reaction (but not cause it on their own):
- Hot environmental temperature: high heat and humidity
- Spicy food
- Pollen: seasonal exposure in those allergic to pollen
- Hormones: in women during the premenstrual or ovulatory phase of menstrual cycle.
Exercise may need to be avoided or modified when the above co-factors are present.
EIA is a complex condition that should be diagnosed and managed by a clinical immunology/allergy specialist. Ask your general practitioner (GP) for a referral if you are not under the care of one.
Management should be individualised for each person depending on the severity and frequency of symptoms, whether food or co-factors are involved and the desire to continue particular sports.
If you have been diagnosed with FDEIA or EIA:
Always be sure to carry your ASCIA Action Plan for Anaphylaxis and your adrenaline (epinephrine) injector/s (such as Anapen®, EpiPen®) with you at all times. Have adrenaline easily accessible, including when you are exercising
Wear a medical identification bracelet or necklace to alert others of the risk of anaphylaxis
Always read medication labels and avoid NSAIDs as advised by your doctor
If you have FDEIA, consider avoiding the trigger food at all times, not just before/after exercise. The reason is that occasionally individuals will develop symptoms when food is consumed and there is no or very little exercise at the time of the allergic reaction. Always read food labels and always disclose your food allergy when eating out. If you do choose to eat the trigger food, eat it at a time when you are planning a quiet night at home (e.g. watching television or reading) with another adult who knows about your allergy and that you have eaten the food. Be sure they can know what to do in an emergency
Exercise with a friend or group (that know about your allergy and your emergency treatment) in case you have an allergic reaction
Always have your charged phone with you in case you need to call triple zero (000) for an ambulance
Exercise first thing in the morning prior to eating when possible
Participate in exercise that can be stopped if necessary, so you don’t ‘push through’ mild symptoms
Stop exercising at the first sign of symptoms (E.g. extreme tiredness, itch, unexpected redness/flushing, hives).
If further allergic reactions happen, what happened up to six hours before and four hours after the allergic reaction should be written down (food, drinks, medicines taken, other possible co-factors) in case other co-factors or triggers may need to be avoided. Make an appointment to speak with your clinical immunology/allergy specialist.
What are the signs of exercise-induced anaphylaxis?
The typical symptoms of an allergic reaction can be mild, moderate or severe in nature.
Mild to moderate signs of an allergic reaction may include:
- Swelling of lips, face, eyes
- Tingling mouth
- Hives or welts
- Abdominal pain, vomiting
Signs of a severe allergic reaction (anaphylaxis) may include any one or more of the following:
- Swelling of the tongue
- Swelling/tightness of the throat
- Difficulty talking and/or hoarse voice
- Difficult/noisy breathing
- Wheeze or persistent cough
- Persistent dizziness or collapse
Treatment in an emergency
Always follow instructions on your ASCIA Action Plan for Anaphylaxis in an emergency.
If you have signs of a severe allergic reaction (anaphylaxis) and you do not have an adrenaline injector with you, lay on the ground (sit on the ground with legs outstretched if breathing is difficult) and call triple zero (000) for an ambulance. Sitting upright quickly or standing can cause a sudden drop of blood pressure and lead to collapse. DO NOT run home. Call out for help if you do not have a phone.
Is EIA a lifelong condition?
It is not known how long EIA persists for, or whether it is a condition that people can grow out of. Regular GP review is recommended to review clinical status, renew adrenaline injector prescriptions and training and to decide if allergy specialist assessment is needed.
For more helpful information on allergy management and emergency treatment of anaphylaxis go to the Australasian Society of Clinical Immunology and Allergy (ASCIA) www.allergy.org.au and Allergy & Anaphylaxis Australia at www.allergyfacts.org.au
Content reviewed July 2021