Which sign indicates anaphylaxis requiring immediate action?

• A. Gradual onset of mild fatigue with no airway symptoms.
• B. Localized swelling only in one area without systemic involvement.
• C. Sudden swelling of the airway with wheezing or dyspnea, hypotension, tachycardia, urticaria, dizziness or loss of consciousness.
• D. High blood pressure with no respiratory symptoms.

Answer: (C)

Anaphylaxis is a medical emergency marked by rapid, widespread involvement of multiple body systems, especially the airway, breathing, and circulation. The sign that indicates this requires immediate action is sudden swelling of the airway with wheezing or dyspnea, along with signs of circulatory involvement such as hypotension and tachycardia, and skin reactions like urticaria, plus dizziness or loss of consciousness. This combination shows the body reacting systemically, with the airway at risk of obstruction and the circulation potentially collapsing, which is why it demands urgent treatment. Immediate steps include administering epinephrine as soon as possible and seeking emergency medical care, while keeping the person lying down and monitoring their condition.

The other scenarios describe reactions that are not systemic or do not involve the airway and/or circulation in a dangerous way, so they do not indicate the same immediate threat as anaphylaxis.