Cholinergic urticaria and exercise-induced anaphylaxis (EIA) are related conditions. Cholinergic urticaria is caused by a rise in body core temperature and usually results in pruritus, skin lesions and, rarely, in serious respiratory and cardiovascular compromise. EIA can result in a cardiovascular compromise and syncope. Ingestion of certain foods may be associated with EIA. A 41-year-old jet pilot complained of 3-month onset of pruritus and urticaria during treadmill exercise. On one occasion, after a routine exercise bout, albeit with pruritus and urticaria, he experienced two short episodes of syncope. Treatment with a nonsedating H1-receptor antagonist was started. He underwent a unique challenge test that we designed. This included passive warming as well as exercising in a hot (temperature of 40°C at 40% humidity) environment. After passing this test uneventfully, the pilot was returned to jet flight with a copilot and, subsequently, to full active duty.