Which of the following symptoms is indicative of anaphylactic reaction?

Anaphylactic reactions are severe, life-threatening allergic reactions that can occur rapidly after exposure to an allergen. One of the hallmark symptoms of an anaphylactic reaction is angioedema, which is the swelling of the deeper layers of the skin and tissues, typically around the eyes, lips, and throat. This swelling can obstruct airways, making it a critical concern during anaphylaxis.

In the context of anaphylaxis, angioedema is often accompanied by other symptoms, which can include respiratory distress, hives, and gastrointestinal symptoms, but the presence of angioedema is particularly significant because it directly indicates a severe allergic response that requires immediate medical intervention.

While nausea and pale, cool skin may also be present in various health conditions, they are not specific indicators of anaphylaxis. Nausea alone can result from many different issues, and pale, cool skin can be indicative of shock or other forms of distress but is not uniquely associated with anaphylactic reactions. Thus, angioedema stands out as a distinct and critical symptom of an anaphylactic event.