Exercise-Induced Allergic Reactions: What Canadians Need to Know

Exercise-induced allergic reactions can develop during or shortly after physical activity. While regular exercise is strongly encouraged for overall health, in rare cases it can trigger serious medical reactions that require prompt first aid and emergency response.

Exercise is capable of triggering the following conditions:

Exercise-Induced Asthma (EIA)

Exercise frequently triggers asthma symptoms in individuals with known asthma. In some cases, asthma symptoms only occur during physical exertion.

Rapid breathing during exercise causes the airways to cool and dry. When they warm again, the airways may narrow (bronchoconstriction), resulting in:

• Wheezing

• Chest tightness

• Shortness of breath

• Coughing

Exercise-Induced Anaphylaxis (Rare but Serious)

In rare cases, strenuous exercise can trigger anaphylaxis, a severe and potentially life-threatening allergic reaction. For some individuals, this only occurs when a specific food is eaten before exercising, a condition known as food-dependent exercise-induced anaphylaxis.

In most cases, symptoms begin 5–10 minutes into strenuous activity or shortly after exercise stops.

Common Symptoms to Watch For

Depending on the condition triggered, symptoms may include:

• Difficulty breathing

• Wheezing or coughing

• Dizziness or faintness

• Hives or flushing

• Swelling of the lips, face, or throat

• Nausea or abdominal discomfort

Any breathing difficulty or signs of anaphylaxis require immediate medical attention.

How Exercise-Induced Allergic Reactions Are Diagnosed

Diagnosis is typically based on:

• A detailed history linking symptoms to physical activity

• Review of food intake prior to exercise (if applicable)

A physician may order an exercise challenge test, where lung function is measured before and after controlled activity on a treadmill or stationary bicycle.

Management and Prevention Strategies

For Exercise-Induced Asthma

The goal of treatment is to allow individuals to exercise safely without symptoms.

Common strategies include:

• Using a short-acting bronchodilator (beta-agonist) about 15 minutes before exercise

• Inhaled medications such as cromolyn

• Long-term asthma control medications when prescribed

• Gradually increasing exercise intensity and duration

• Maintaining overall physical fitness, which often reduces symptom severity

For Exercise-Induced Anaphylaxis

• Avoid the activity that triggered the reaction if possible

• Do not consume identified trigger foods before exercising

• Always carry a self-injectable epinephrine auto-injector

• Exercise with others whenever possible

• Seek immediate emergency care if symptoms develop

First Aid and Emergency Awareness in Canada

Exercise-induced allergic reactions highlight why first aid, CPR, and anaphylaxis training are critical skills for Canadians—especially coaches, fitness professionals, parents, teachers, and workplace safety personnel.

Knowing how to:

• Recognize early warning signs

• Administer epinephrine

• Activate emergency medical services
  can save lives.

Important Disclaimer

Educational Use Only
The information on this page is intended for first aid awareness and general education. It is not a substitute for medical advice, diagnosis, or treatment. Anyone experiencing breathing difficulty, fainting, or signs of anaphylaxis during or after exercise should seek emergency medical care immediately.

Participation in first aid and CPR training supports early recognition and emergency response but does not replace professional medical care.