Which of the following is a sign of anaphylaxis?

Shortness of breath is a significant sign of anaphylaxis, which is a severe and potentially life-threatening allergic reaction. During anaphylaxis, the body releases a large amount of histamine and other chemicals that can lead to severe swelling, particularly in the airways. This swelling can result in difficulty breathing, wheezing, and a sense of tightness in the chest, which makes shortness of breath a critical indicator of this condition.

Recognizing shortness of breath as a sign of anaphylaxis is crucial for timely intervention, as individuals experiencing this symptom may require immediate medical attention, such as the administration of epinephrine. The other options, while they may indicate other medical issues or allergic reactions, do not directly correlate with the acute respiratory distress that characterizes anaphylaxis.