You probably know someone who is severely allergic to something, like peanuts or bee stings. These allergies can cause anaphylaxis, a type of severe reaction that affects your whole body. It happens quickly and can lead to life threatening complications.

In rare cases, anaphylaxis can also occur due to physical activity. A combination of exercise and other contributing factors — such as food, weather conditions, or medications — can lead to exercise-induced anaphylaxis.

Vigorous forms of exercise are usually blamed for exercise-induced anaphylaxis. But it can occur during any type of physical activity, including raking leaves or tearing it up on the dance floor.

Eating particular foods before exercising may bring on an allergic reaction. Peanuts, shellfish, tomatoes, corn, and wheat are associated with exercise-induced anaphylaxis, although any food can be a trigger. This is referred to as food-dependent exercise-induced anaphylaxis.

Other potential triggers of exercise-induced anaphylaxis include:

  • certain medications, such as aspirin and anti-inflammatories
  • extreme temperatures
  • humidity
  • hormonal changes

Symptoms of exercise-induced anaphylaxis can come on suddenly. They may be mild at first but can progress rapidly. Common symptoms include:

  • hives
  • nausea
  • dizziness
  • swelling
  • cramps
  • diarrhea
  • coughing, wheezing, or difficulty breathing

Exercise-induced anaphylaxis can progress into a life threatening situation that requires immediate medical attention. Severe cases may progress to shock or loss of consciousness and can even cause you to stop breathing and your heart to stop beating.

If you feel early symptoms of exercise-induced anaphylaxis, stop what you’re doing and rest. Sometimes, that’s all it takes to prevent symptoms from progressing.

However, if you or someone nearby is experiencing worsening symptoms, call 911 immediately. Symptoms of escalating anaphylactic shock include:

  • pale, clammy skin
  • a weak, rapid pulse
  • difficulty breathing
  • confusion and loss of consciousness

If the person has emergency medication, such as an epinephrine auto-injector, you might need to help them administer it. Do not try to give them any oral medications if they’re having trouble breathing.

It may be necessary to start CPR while waiting for emergency responders to arrive. If you don’t know how to perform CPR, try to find someone who does.

The emergency medical team will try to help the person breathe and keep their heart beating. They may use epinephrine to reduce the body’s allergic response.

Emergency responders might also use intravenous (through the veins) antihistamines or cortisone to decrease inflammation in the air passages. The allergic reaction can cause the airways to become so inflamed that they close up, blocking airflow to the lungs. Medications known as beta-agonists can also help individuals breathe more easily.

Pinpointing the factors that contribute to anaphylaxis will help you prevent future attacks.

If you’ve experienced exercise-induced anaphylaxis, consult a doctor for a complete physical examination. Keep a record of the foods you eat and the conditions you are in before you exercise. Figure out how long before exercise you should avoid the food or other triggers that may have led to the reaction.

Avoid exercising outdoors during allergy season and in extreme temperatures. Additionally, exercise with a partner who is aware of your condition and will know what to do in an emergency.

Your doctor will probably prescribe an epinephrine auto-injector (often known by the brand name EpiPen) if you have exercise-induced anaphylaxis. This tool injects epinephrine into your system to slow down the allergic reaction.

Seconds count, so make sure you understand how and when to use the auto-injector. Tell those closest to you that you carry an auto-injector and teach them how to use it.

An epinephrine injection does not cure anaphylaxis — it just slows down the allergic reaction. Be sure to go to the hospital immediately after using the auto-injector.

It’s important that you carry an auto-injector with you at all times and replace it before it expires.

Anaphylaxis is usually very treatable if you act quickly. If you have a known allergy, carry your medications with you when you exercise — especially your epinephrine auto-injector.

Try to avoid any known allergy triggers. Always remember that this is a serious allergy, and you must treat it as such. Possible complications of anaphylaxis can include loss of consciousness, shock, respiratory arrest, and cardiac arrest, which can lead to death.

Here are some additional steps you can take to keep yourself safe:

  • Tell your family and friends about your condition and teach them what to do in an emergency.
  • Consider wearing a medical alert tag that indicates you have an allergy.
  • If you have a food allergy, read all food labels carefully.
  • Stop and rest at the first sign of anaphylaxis.
  • Keep your medications and cellphone with you when you’re exercising.

Exercise is good for you, but it can become dangerous if you experience exercise-induced anaphylaxis. However, as long as you take the proper precautions and listen to your body’s signals, you should be able to continue exercising.