What indicates anaphylactic shock?

• A. Ventricular fibrillation
• B. Violent reaction to an allergen
• C. Fluid loss due to vomiting
• D. Cardiac tamponade

Answer: (B)

Anaphylactic shock is a severe, potentially life-threatening allergic reaction that occurs rapidly after exposure to an allergen. The key indicator of anaphylactic shock is the violent reaction to an allergen, which typically manifests as a combination of symptoms. These symptoms can include difficulty breathing, swelling of the throat and tongue, hives, hypotension (low blood pressure), and gastrointestinal symptoms like nausea and vomiting.

During anaphylaxis, the body releases a large amount of histamine and other chemicals, causing widespread vasodilation and increased permeability of blood vessels. This can lead to a drop in blood pressure and difficulties in breathing, which are critical aspects of the condition. Recognizing this violent systemic response to allergens is essential for prompt treatment, usually with epinephrine, to counteract the severe effects on the body.

The other options mentioned do not specifically represent the characteristics of anaphylactic shock. For example, ventricular fibrillation relates to erratic heart rhythms, fluid loss due to vomiting can occur in various situations but is not exclusive to anaphylaxis, and cardiac tamponade involves fluid accumulation around the heart which compromises its function. Therefore, the distinguishing feature of anaphylactic shock is indeed the violent reaction to an allergen.