Emergency Medical Technician (EMT) Intermediate Practice Exam

Which patient is likely to experience the most severe allergic reaction due to previous exposure?

1. A 20-year-old male who has never been stung

2. A 35-year-old male who is allergic to bees

3. A 40-year-old female who was stung by a yellow jacket

4. A 50-year-old female with no known allergies

The correct answer is: A 40-year-old female who was stung by a yellow jacket

The patient who is likely to experience the most severe allergic reaction is the 40-year-old female who was stung by a yellow jacket. This patient has had a previous exposure to an allergen, in this case, the venom from a yellow jacket sting, which can potentially lead to sensitization. When individuals are sensitized to a specific allergen, their immune system produces specific antibodies (IgE) that can trigger a more intense allergic response upon subsequent exposures. Since this patient has already experienced a sting, there is a likelihood that her body has developed an immunological memory to the venom, placing her at greater risk for a severe allergic reaction, such as anaphylaxis, if stung again. In contrast, the other patients listed either have no history of exposure to allergens (which would suggest a lower likelihood of a severe reaction) or have lower risks associated with their specific situations. The key factor here is the prior exposure that can lead to an increased immunological response in the case of subsequent encounters with the allergen.