People who don’t like to workout will sometimes joke that they’re “allergic” to exercise. But what many don’t realise is that an allergy to exercise is a real thing – and it can be dangerous if not caught in time.

Exercise-induced anaphylaxis (EIA) is a rarely heard of severe allergic reaction to moderate exercise. It can cause intense itching all over the body, followed rapidly by an inability to breathe. It’s estimated that between 2.3% to 5% of all cases of anaphylaxis globally are triggered by exercise.

EIA was first identified in the 1970s by doctors in Colorado after a 30-year-old long-distance runner was hospitalised multiple times, a few days apart, while he was out on a run.

Further testing revealed that his blood contained all the tell-tale signatures of anaphylaxis (an allergic reaction). Intrigued, they investigated further and quickly discovered that the runner only developed allergic symptoms when he exercised after eating seafood. When he didn’t eat seafood before exercise, he had no symptoms.

It’s now well established that not all cases of EIA are triggered by food allergens. This sub-type is known specifically as food dependent EIA. It’s commonly triggered by foods such a shellfish, nuts, eggs, milk and wheat.

But EIA symptoms can also arise when exercise follows exposure to a range of other factors, including certain medications,........

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